3
Cambridge Engineering Dept Fluids Seminars
http://sms.cam.ac.uk/collection/2363417
Recordings of seminars given in the Cambridge University Engineering Department in the Fluid Mechanics series.
1440
2019
Mon, 16 Dec 2019 09:14:27 +0000
Mon, 21 Nov 2016 12:40:59 +0000
en
smssupport@ucs.cam.ac.uk
Cambridge Engineering Dept Fluids Seminars
http://sms.cam.ac.uk/collection/2363417
http://rss.sms.cam.ac.uk/images/cam/identifier2.png
http://video.search.yahoo.com/mrss
Cambridge Engineering Dept Fluids Seminars
Recordings of seminars given in the Cambridge University Engineering Department in the Fluid Mechanics series.
Cambridge Engineering Dept Fluids Seminars
Recordings of seminars given in the Cambridge University Engineering Department in the Fluid Mechanics series.
Cambridge University
Dr N.C Daish
ncd1@cam.ac.uk
http://sms.cam.ac.uk/collection/2363417
Cambridge Engineering Dept Fluids Seminars
20161121T12:40:59+00:00
ENG
no

Baroclinic Adjustment Revisited: in Atmospheric and Laboratory Models of Rotating Stratified Flows by Peter Read (Oxford)
ucs_sms_2363417_3021931
http://sms.cam.ac.uk/media/3021931
Baroclinic Adjustment Revisited: in Atmospheric and Laboratory Models of Rotating Stratified Flows by Peter Read (Oxford)
Thu, 11 Jul 2019 12:15:15 +0100
University of Cambridge
Prof Peter Read
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fabb0f934dfad10d6291d6002ed81d10
d932540d4723e555f3b35debb07efd35
0d8c9a43766ab927009693b57bb97473
Cambridge University
2701
http://sms.cam.ac.uk/media/3021931
Baroclinic Adjustment Revisited: in Atmospheric and Laboratory Models of Rotating Stratified Flows by Peter Read (Oxford)
It is 40 years now since the publication of a pioneering study by Peter Stone that proposed the hypothesis that baroclinic instabilities act to hold the Earth’s atmosphere close to a marginally unstable state as a form of selforganized criticality, thereby exerting control over the heat transport and thermal structure of the extratropical atmosphere. This is in contrast to the tropics, where the vertical lapse rate seems to be largely determined by (moist) convective adjustment. More recent studies, however, have questioned this approach, raising alternative impacts of equilibrating baroclinic eddies on nonlinear macroturbulent cascades and atmospheric stability, and the whole question of what determines the thermal structure of the midlatitude atmosphere remains inadequately understood.
In this talk I will outline some ongoing new work in which we are attempting to address these issues (a) using laboratory experiments on rotating, stratified flows that combine regions of free convection with baroclinic instability, and (b) using highly simplified atmospheric circulation models with widely differing rotation rates. The results help to quantify some of the effects of both baroclinic and convective adjustment effects on largescale circulation across wide ranges of parameter space, even without moist convection, indicating that baroclinic adjustment effects are particularly strong for Earth and Marslike planets. The implications for various planetary atmospheres will be discussed.
20190725T15:46:49+01:00
2701
3021931
true
4x3
false
no

Bioinspired aerofoil adaptations for the reduction of turbulence interaction noise by Lorna Ayton (DAMTP, Cambridge)
ucs_sms_2363417_3021893
http://sms.cam.ac.uk/media/3021893
Bioinspired aerofoil adaptations for the reduction of turbulence interaction noise by Lorna Ayton (DAMTP, Cambridge)
Please note the first part of this talk is missing due to technical problems.
Thu, 11 Jul 2019 12:09:35 +0100
University of Cambridge
Dr Lorna Ayton
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c90f62f74e0c530512a84ded78d96811
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eb513a8acab7d710227413e96e36ecbc
Please note the first part of this talk is missing due to technical problems.
Please note the first part of this talk is missing due to technical problems.
Cambridge University
2037
http://sms.cam.ac.uk/media/3021893
Bioinspired aerofoil adaptations for the reduction of turbulence interaction noise by Lorna Ayton (DAMTP, Cambridge)
Please note the first part of this talk is missing due to technical problems.
A dominant source of broadband aeroengine noise arises when the unsteady wakes shed from rotors interact with downstream stators. This socalled leadingedge noise cannot be eliminated, but it can be reduced. By altering the spanwise geometry of the leading edge of an aerofoil it is known through experimental testing that leadingedge noise can be significantly reduced over broadband frequencies. In recent years, a multitude of different shapes have been tested and all are seen to have benefits for different frequency ranges, which may be ideal for the reduction of tonal noise, but the question remains; which design is optimal for broadband noise reduction?
This talk presents a theoretical model for leadingedge noise, both for straight edges and serrated edges. Through theoretical optimisation, a set of rules are proposed which lead to an optimal design for broadband leadingedge noise reduction. Experimental data on sample new designs validates the theoretical predictions and illustrates up to an additional 7dB noise reduction verses conventional serrated designs.
20190725T15:47:18+01:00
2037
3021893
true
4x3
false
no

Cardiac acoustics and a smart stethoscope by Edmund Kay (Cambridge)
ucs_sms_2363417_2590438
http://sms.cam.ac.uk/media/2590438
Cardiac acoustics and a smart stethoscope by Edmund Kay (Cambridge)
Talk given by Edmund Kay (CUED) at Department of Engineering, University of Cambridge, 20 October 2017, as part of the CUED Fluids seminar series.
The talk describes techniques to analyse heart sound spectra to detect murmurs and infer valvular heart disease.
Tue, 24 Oct 2017 11:25:43 +0100
sound spectra,heart murmur,heart disease,machine learning algorithm,stethoscope,cardiac acoustics
103
103100
103
103107
109
109103
101
University of Cambridge
Edmund Kay
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Talk given by Edmund Kay (CUED) at Department of Engineering, University of...
Talk given by Edmund Kay (CUED) at Department of Engineering, University of Cambridge, 20 October 2017, as part of the CUED Fluids seminar series.
The talk describes techniques to analyse heart sound spectra to detect murmurs and infer valvular heart disease.
Cambridge University
1823
sound spectra,heart murmur,heart disease,machine learning algorithm,stethoscope,cardiac acoustics
http://sms.cam.ac.uk/media/2590438
Cardiac acoustics and a smart stethoscope by Edmund Kay (Cambridge)
Talk given by Edmund Kay (CUED) at Department of Engineering, University of Cambridge, 20 October 2017, as part of the CUED Fluids seminar series.
The talk describes techniques to analyse heart sound spectra to detect murmurs and infer valvular heart disease.
Cardiovascular disease is the leading cause of mortality worldwide, causing 31% of all deaths. We investigate valvular heart diseases which create characteristic sounds, called murmurs. Using an invitro model of aortic stenosis (the most common valvular heart disease) we analyse the sound spectra of the murmur it produces. Using our understanding of this and other common murmurs, we have produced a machine learning algorithm which can detect these murmurs with an accuracy of up to 95%. This algorithm will be used to build an intelligent stethoscope, capable of automatically analysing heart sounds, to improve diagnosis worldwide.
20171024T11:25:43+01:00
1823
2590438
true
4x3
false
no

Decaying twodimensional turbulence undergoes statistical heating by Gavin Esler (UCL)
ucs_sms_2363417_3104530
http://sms.cam.ac.uk/media/3104530
Decaying twodimensional turbulence undergoes statistical heating by Gavin Esler (UCL)
Talk given by Prof Gavin Esler (University College London) at Department of Engineering, University of Cambridge, 8 November 2019, as part of the CUED Fluids seminar series.
Thu, 21 Nov 2019 09:12:14 +0000
University of Cambridge
Prof Gavin Esler
f32489a81c48f3667d2d4b840a35580b
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Talk given by Prof Gavin Esler (University College London) at Department of...
Talk given by Prof Gavin Esler (University College London) at Department of Engineering, University of Cambridge, 8 November 2019, as part of the CUED Fluids seminar series.
Cambridge University
2494
http://sms.cam.ac.uk/media/3104530
Decaying twodimensional turbulence undergoes statistical heating by Gavin Esler (UCL)
Talk given by Prof Gavin Esler (University College London) at Department of Engineering, University of Cambridge, 8 November 2019, as part of the CUED Fluids seminar series.
An emergent property of decaying twodimensional turbulence is shown to be a weak but persistent statistical heating, or tendency towards clustering of likesigned vortices. The rate of this heating, which is driven by changes to the vortex population due to vortex mergers and straining events, provides a strong constraint on both vortex decay laws and kinetic theories of vortex interactions. A quasiequilibrium statistical theory determines the energy spectrum from just the vortex interaction energy and bulk information about the number density of the vortices. The emergent heating rate is shown to determine the upscale transfer of energy, and is a powerful constraint on power law descriptions of the evolving vortex population.
20191121T09:12:14+00:00
2494
3104530
true
4x3
false
no

Discovering new features in supersonic wind tunnels: Stories from collaboration with CFD by Kshitij Sabnis (Cambridge)
ucs_sms_2363417_3110763
http://sms.cam.ac.uk/media/3110763
Discovering new features in supersonic wind tunnels: Stories from collaboration with CFD by Kshitij Sabnis (Cambridge)
Talk given by Kshitij Sabnis (University of Cambridge) at Department of Engineering, University of Cambridge, 22 November 2019, as part of the CUED Fluids seminar series.
Wed, 27 Nov 2019 16:29:22 +0000
University of Cambridge
Kshitij Sabnis
cb4e44b452338494a63153fcea01ff8a
5c2b7a04ff0ca8a0c34659749382c4a1
6b8866a9d81603c96e0e4fac2e2ec83a
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Talk given by Kshitij Sabnis (University of Cambridge) at Department of...
Talk given by Kshitij Sabnis (University of Cambridge) at Department of Engineering, University of Cambridge, 22 November 2019, as part of the CUED Fluids seminar series.
Cambridge University
2087
http://sms.cam.ac.uk/media/3110763
Discovering new features in supersonic wind tunnels: Stories from collaboration with CFD by Kshitij Sabnis (Cambridge)
Talk given by Kshitij Sabnis (University of Cambridge) at Department of Engineering, University of Cambridge, 22 November 2019, as part of the CUED Fluids seminar series.
Fluid dynamics researchers today often aspire to use CFD and experiments in combination to better understand flow physics. However, it is relatively unusual for the physical experiments and simulations to be designed and conducted simultaneously. I will be talking about a recent study to validate numerical codes in the corner regions of supersonic channel flows, where a specific emphasis was placed on close experimentalcomputational collaboration. I will give examples of how this close communication between the two approaches enabled the discovery of new features in the flow of a supersonic wind tunnel, which has produced more than sixty years of highquality research. These features include a somewhat unexpected shape of the tunnel boundary layers, which can have a profound influence on wind tunnel experiments, as well as streamwise vortices induced by the nozzle geometry.
20191128T10:31:24+00:00
2087
3110763
true
4x3
false
no

Dynamics of Marine Ice Sheets by Grae Worster (DAMTP, Cambridge)
ucs_sms_2363417_3021830
http://sms.cam.ac.uk/media/3021830
Dynamics of Marine Ice Sheets by Grae Worster (DAMTP, Cambridge)
Thu, 11 Jul 2019 11:55:37 +0100
University of Cambridge
Prof Grae Worster
4aa3016309a57fd2f02dea7ea0cc1d47
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f2b854fee6b4e44d12ed6e77380f0bb5
be0bfe7a4a9a75895077f3422e72a2e1
Cambridge University
2966
http://sms.cam.ac.uk/media/3021830
Dynamics of Marine Ice Sheets by Grae Worster (DAMTP, Cambridge)
On short length and time scales, ice behaves as a brittle, elastic solid but on continental length scales and timescales of years or longer, ice flows as a viscous fluid. The West Antarctic Ice Sheet, for example, sits on bedrock that is 1–2 kilometres below sea level. The ice itself is 4–5 kilometres thick in the central regions but thins as it flows towards the margins and eventually becomes thin enough to float on the ocean as a socalled ice shelf. The locus of detachment from the bedrock, where the ice sheet first starts to float, is called the grounding line. The position of the grounding line is determined dynamically, and there is concern to understand the conditions under which the grounding line would recede and allow the ice sheet to flow ever faster into the ocean, causing global sea levels to rise. I will present some simple fluidmechanical experiments and mathematical models to address some of the fundamental physical balances that control the stability of grounding lines.
20190725T15:50:08+01:00
2966
3021830
true
4x3
false
no

Effective boundary conditions at a regularly microstructured wall by Alessandro Bottaro (University of Genoa)
ucs_sms_2363417_3123851
http://sms.cam.ac.uk/media/3123851
Effective boundary conditions at a regularly microstructured wall by Alessandro Bottaro (University of Genoa)
Talk given by Prof Alessandro Bottaro (Università di Genova) at Department of Engineering, University of Cambridge, 6 December 2019, as part of the CUED Fluids seminar series.
Mon, 16 Dec 2019 09:14:27 +0000
University of Cambridge
Prof Alessandro Bottaro
48cbbfdfff76957c040a250caa4ffc02
bcb4b6dba055a324f4639880adf46432
801678be5dbd5ecc9433ccaae1e9ca91
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4c3f7011f0a82bdd2020d7c3112d55e0
a65f1e47ee86f08c3e3df65aad3a5fe4
Talk given by Prof Alessandro Bottaro (Università di Genova) at Department of...
Talk given by Prof Alessandro Bottaro (Università di Genova) at Department of Engineering, University of Cambridge, 6 December 2019, as part of the CUED Fluids seminar series.
Cambridge University
3298
http://sms.cam.ac.uk/media/3123851
Effective boundary conditions at a regularly microstructured wall by Alessandro Bottaro (University of Genoa)
Talk given by Prof Alessandro Bottaro (Università di Genova) at Department of Engineering, University of Cambridge, 6 December 2019, as part of the CUED Fluids seminar series.
The talk will discuss effective boundary conditions, correct to second order in a small parameter epsilon, for a rough wall with periodic microindentations. The length scale of the indentations is l, and epsilon = l/L << 1, with L a characteristic length of the macroscopic problem. At leading order the Navier slip condition is recovered; at next order the slip velocity includes a term arising from the streamwise pressure gradient. At second order also a transpiration velocity appears at the fictitious wall where the effective boundary conditions are enforced. For ease of derivation, the microscopic theory, based on a power series expansion of the dependent variables, will be limited to the case of two dimensional roughness, the threedimensional extension being trivial. The application to a macroscopic problem is carried out considering the case of the Hiemenz stagnation point flow over a rough wall.
20191216T09:14:27+00:00
3298
3123851
true
4x3
false
no

Energy spectrum for buoyancydriven turbulence by Abhishek Kumar (Coventry)
ucs_sms_2363417_2678497
http://sms.cam.ac.uk/media/2678497
Energy spectrum for buoyancydriven turbulence by Abhishek Kumar (Coventry)
Talk given by Dr Abhishek Kumar (Applied Mathematics Research Centre, Coventry University) at Department of Engineering, University of Cambridge, 16 February 2018, as part of the CUED Fluids seminar series.
The talk discusses turbulent buoyancydriven flows, and describes investigations with DNS into the wavenumber scaling of fluxes of kinetic and potential energy for stablystratified flow and RayleighBenard convection.
Tue, 27 Feb 2018 14:39:33 +0000
buoyancydriven flows,RayleighBenard convection,stablystratified turbulence,thermal convection,thermallydriven turbulence
101
108
108100
109
109109
University of Cambridge
Dr Abhishek Kumar
1e0c08ef8f9e2f83f1a034dfd3f1a15a
53a4f34036ed9f24bd2b3d8db9211b13
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7a535ec54a82a91f26b0df4419d82b94
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91f4854cc4530a0cf43dcc0e54fd6ad4
Talk given by Dr Abhishek Kumar (Applied Mathematics Research Centre, Coventry...
Talk given by Dr Abhishek Kumar (Applied Mathematics Research Centre, Coventry University) at Department of Engineering, University of Cambridge, 16 February 2018, as part of the CUED Fluids seminar series.
The talk discusses turbulent buoyancydriven flows, and describes investigations with DNS into the wavenumber scaling of fluxes of kinetic and potential energy for stablystratified flow and RayleighBenard convection.
Cambridge University
2039
buoyancydriven flows,RayleighBenard convection,stablystratified turbulence,thermal convection,thermallydriven turbulence
http://sms.cam.ac.uk/media/2678497
Energy spectrum for buoyancydriven turbulence by Abhishek Kumar (Coventry)
Talk given by Dr Abhishek Kumar (Applied Mathematics Research Centre, Coventry University) at Department of Engineering, University of Cambridge, 16 February 2018, as part of the CUED Fluids seminar series.
The talk discusses turbulent buoyancydriven flows, and describes investigations with DNS into the wavenumber scaling of fluxes of kinetic and potential energy for stablystratified flow and RayleighBenard convection.
Buoyancydriven flows are often encountered in geophysics, astrophysics, atmospheric and solar physics, and engineering. In general, these flows come in two categories: stably stratified flows and RayleighBénard convection (RBC). Turbulent aspects of these flows are an active field of research. An important unsolved problem in this field is how to quantify the smallscale quantities, e.g., spectra and fluxes of kinetic energy (KE) and potential energy (PE) of these flows. Using direct numerical simulations performed at high resolution, we demonstrate that the stably stratified turbulence at moderate stratification exhibits BolgianoObukhov scaling, due to the conversion of kinetic energy to potential energy via buoyancy. We show that the KE flux decreases with the wavenumber (k) which yield k and k^(7/5) scaling for KE and PE spectra respectively. For RBC , we performed simulation at grid resolution 4096^3 on a cubical box and have shown a delicate balance of dissipation and energy supply rate by buoyancy. This balance leads to a constant KE flux and rules out the BolgianoObukhov scaling, and we observe Kolmogorov’s spectrum [13]. References: [1] Kumar, Chatterjee, and Verma, Phys. Rev. E, 90, 023016 (2014). [2] Kumar and Verma, Phys. Rev. E, 91, 043014 (2015). [3] Verma, Kumar, and Pandey, New J. Phys., 19, 025012 (2017).
20180228T14:24:05+00:00
2039
2678497
true
4x3
false
no

Extrapolating turbulence to higher Re by Sergei Chernyshenko (ICL)
ucs_sms_2363417_2419059
http://sms.cam.ac.uk/media/2419059
Extrapolating turbulence to higher Re by Sergei Chernyshenko (ICL)
Talk given by Prof Sergei Chernyshenko (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 10 February 2017, as part of the CUED Fluids seminar series.
The talk discusses methods for extrapolating turbulencerelated results from DNS and wind tunnel experiments to higher Re. The recentlydeveloped quasisteady quasihomogeneous (QSQH) theory, which relates nearwall turbulence to outer largescale turbulent structures, is described, and some initial results from the theory, on extrapolating turbulence statistics to higher Re, are given.
Tue, 14 Feb 2017 16:03:45 +0000
Turbulence,Turbulence modelling,Large Re flows,Turbulent largescale structures,QSQH theory,Quasisteady,Quasihomogeneous
101
108
108100
University of Cambridge
Sergei Chernyshenko
73c76e40571dbb5cd4a4cc317a366e01
b0d9f0a2e47901fb77e61888560b53a9
449109633ba1e6b9bf5a8187f12e1808
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0dcf684a08bd42ef0fd85944a4ad1369
5e9a1ff670a1ea0f48617e8bc8cfca71
Talk given by Prof Sergei Chernyshenko (Department of Aeronautics, Imperial...
Talk given by Prof Sergei Chernyshenko (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 10 February 2017, as part of the CUED Fluids seminar series.
The talk discusses methods for extrapolating turbulencerelated results from DNS and wind tunnel experiments to higher Re. The recentlydeveloped quasisteady quasihomogeneous (QSQH) theory, which relates nearwall turbulence to outer largescale turbulent structures, is described, and some initial results from the theory, on extrapolating turbulence statistics to higher Re, are given.
Cambridge University
3119
Turbulence,Turbulence modelling,Large Re flows,Turbulent largescale structures,QSQH theory,Quasisteady,Quasihomogeneous
http://sms.cam.ac.uk/media/2419059
Extrapolating turbulence to higher Re by Sergei Chernyshenko (ICL)
Talk given by Prof Sergei Chernyshenko (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 10 February 2017, as part of the CUED Fluids seminar series.
The talk discusses methods for extrapolating turbulencerelated results from DNS and wind tunnel experiments to higher Re. The recentlydeveloped quasisteady quasihomogeneous (QSQH) theory, which relates nearwall turbulence to outer largescale turbulent structures, is described, and some initial results from the theory, on extrapolating turbulence statistics to higher Re, are given.
In many practical applications, the Reynolds number Re is much greater than the largest Re that can be achieved in direct numerical simulations and windtunnel experiments. Hence, to apply the turbulencerelated results obtained in a wind tunnels or with computers, extrapolation to higher Re is needed. For the part of the flow very close to the wall such extrapolation is usually based on the classical universality hypothesis stating that near the wall the turbulent flow parameters, expressed in socalled wall units, are independent of Re. However, in recent years it was established that the largescale structures residing further away from the wall affect the nearwall turbulence. Since these structures, if expressed in wall units, are not Reindependent, the classical universality hypothesis is not correct. Moreover, recent data indicate that as Re increases the outer largescale structures become stronger. An outline will be given of the new technique for extrapolating statistical characteristics of nearwall turbulence from medium to higher Re, based on the recently developed quasisteady quasihomogeneous (QSQH) theory. The QSQH theory is an alternative to the classical universality hypothesis. The QSQH theory provided relationships between many turbulence parameters previously thought to be unrelated, including for example those entering the wellknown empirical formula for the modulation of nearwall turbulence by outer structures, and threw a new light on the Redependence of the logarithmic law constants. First results on extrapolating turbulence statistics to higher Re will also be presented.
20170221T17:50:13+00:00
3119
2419059
true
4x3
false
no

Finding the halo: a separated vortex ring underlies the flight of the dandelion by Ignazio Viola (Edinburgh)
ucs_sms_2363417_3104512
http://sms.cam.ac.uk/media/3104512
Finding the halo: a separated vortex ring underlies the flight of the dandelion by Ignazio Viola (Edinburgh)
Talk given by Dr Ignazio Viola (University of Edinburgh) at Department of Engineering, University of Cambridge, 1 November 2019, as part of the CUED Fluids seminar series.
Thu, 21 Nov 2019 09:00:56 +0000
University of Cambridge
Dr Ignazio Viola
2ddd80c24403ab8d85a945d3efbf9bdf
65fd4c507e96d8413fb32ed933277cdd
3aa419088b919eed6c8dac77f068e1b6
6b767e5efd84b74943a30bd365d8ba39
c2bb2f48d9cb9dd6782314b6c29b2caa
ec47849335e96d7d64e9fe3bc2961037
Talk given by Dr Ignazio Viola (University of Edinburgh) at Department of...
Talk given by Dr Ignazio Viola (University of Edinburgh) at Department of Engineering, University of Cambridge, 1 November 2019, as part of the CUED Fluids seminar series.
Cambridge University
3110
http://sms.cam.ac.uk/media/3104512
Finding the halo: a separated vortex ring underlies the flight of the dandelion by Ignazio Viola (Edinburgh)
Talk given by Dr Ignazio Viola (University of Edinburgh) at Department of Engineering, University of Cambridge, 1 November 2019, as part of the CUED Fluids seminar series.
In this talk I will provide a brief overview of the research on applied fluid dynamics and vortexdominated flow in my research group, and I will present indepth our recent findings on the flight of the dandelion fruit (https://doi.org/10.1038/s4158601806042).
The dandelion uses a bundle of bristles, known as the pappus, to enhance the drag and to slow down its descent. This passive flight mechanism allows the dandelion to be carried by the wind for even hundreds of miles. The underlying fluid dynamics of this dragenhancing mechanism was, however, unknown. We found that when the dandelion falls, the air flows through the pappus and forms a bubble of recirculating flow. This bubble, which we named the separated vortex ring (SVR), sits stably a few millimetres above the dandelion, like a halo.
In this talk I will describe how we discovered this extraordinary new type of vortex, and what we have learnt of it. The discovery of the SVR suggests the existence in nature of a new type of locomotion. We envisage that this discovery might contribute to explain the function of many hairy structures in the plant and animal kingdoms. We also envisage that it may contribute to the design of micro aerial vehicles that will be passively carried by the wind.
The research on the dandelion fruit is a collaboration with the research groups of Dr Naomi Nakayama (School of Biological Sciences) and Dr Enrico Mastropaolo (School of Engineering) at the University of Edinburgh.
20191121T09:00:56+00:00
3110
3104512
true
4x3
false
no

Fluid Mechanics of Flow in the Upper Airways by Denis Doorly (ICL)
ucs_sms_2363417_3021872
http://sms.cam.ac.uk/media/3021872
Fluid Mechanics of Flow in the Upper Airways by Denis Doorly (ICL)
Thu, 11 Jul 2019 12:06:24 +0100
University of Cambridge
Prof Denis Doorly
64cb30ca40c9af87921cc8aba9817bc3
02bf8f5832fb15abde5f2cc18bee0d84
0263fcb92d13d23d1f714d844ceee38a
87a9a8ab0eb264a419a576693af393fe
244fd69e0d485256a68d49d141f3ec7e
323cc537e2c64ed889585eec2d86f5f8
Cambridge University
2984
http://sms.cam.ac.uk/media/3021872
Fluid Mechanics of Flow in the Upper Airways by Denis Doorly (ICL)
What is the connection between fluid mechanics and upper airway physiology? How complicated is the fluid mechanics and what is it telling us?
These are questions which I hope to answer (well, only partly) in this informal talk. First we will look at how to place our study in an engineering context: geometry, flow boundary conditions and (briefly) equations. Various experimental methods and some very large scale computations will be described, and means to characterise performance discussed. We will then consider how to address some problems that are important in understanding and treating disease. At this point it should become clear that we know rather little and that there are great challenges that call for more work in this area.
20190725T15:48:16+01:00
2984
3021872
true
4x3
false
no

Giant volcanic intrusions by Herbert Huppert (Cambridge)
ucs_sms_2363417_2367665
http://sms.cam.ac.uk/media/2367665
Giant volcanic intrusions by Herbert Huppert (Cambridge)
Talk given by Prof Herbert Huppert (Department of Applied Mathematics & Theoretical Physics, University of Cambridge) at Department of Engineering, University of Cambridge, 25 November 2016, as part of the CUED Fluids seminar series.
The talk discusses models of the horizontal intrusion of a volcanic plume that has reached the height of neutral density in a stratified atmosphere, including the effects of drag and wind. The rate of lateral spreading with downstream distance is also considered.
Mon, 28 Nov 2016 14:45:34 +0000
Volcanic eruption,Volcanic plume,plume,intrusion,stratified atmosphere
101
101104
109
109102
109
109109
University of Cambridge
Herbert Huppert
a9790b013e2f291cc6e95f3aabc76a42
08a8051d7e071774160d4b8f765bb855
a57ee1e6325e46818c337440f215dc74
604e1618c611c7eff8d3726c6c3f4855
8078bab4d98003f9ee114e4e1f1619c0
1400e81c3dc4dae80c7c01b4ddb48dd7
Talk given by Prof Herbert Huppert (Department of Applied Mathematics &...
Talk given by Prof Herbert Huppert (Department of Applied Mathematics & Theoretical Physics, University of Cambridge) at Department of Engineering, University of Cambridge, 25 November 2016, as part of the CUED Fluids seminar series.
The talk discusses models of the horizontal intrusion of a volcanic plume that has reached the height of neutral density in a stratified atmosphere, including the effects of drag and wind. The rate of lateral spreading with downstream distance is also considered.
Cambridge University
2696
Volcanic eruption,Volcanic plume,plume,intrusion,stratified atmosphere
http://sms.cam.ac.uk/media/2367665
Giant volcanic intrusions by Herbert Huppert (Cambridge)
Talk given by Prof Herbert Huppert (Department of Applied Mathematics & Theoretical Physics, University of Cambridge) at Department of Engineering, University of Cambridge, 25 November 2016, as part of the CUED Fluids seminar series.
The talk discusses models of the horizontal intrusion of a volcanic plume that has reached the height of neutral density in a stratified atmosphere, including the effects of drag and wind. The rate of lateral spreading with downstream distance is also considered.
I would present a brief description of a volcanic eruption, the formation of a volcanic plume and its intrusion at the height of neutral density into the stratified atmosphere; the intrusion rate determined by balance of forces, by balance of terms in the governing equations and by a similarity form of solution, all of which agree, but are, unfortunately, incorrect! I will go on to develop the correct, quite different, solution and account for the extra effects of drag and wind. I will end with an observational graph, which I like, but some others don’t, collapsing the data for spread as a function of downstream distance, an aspect I am still working on.
20170221T17:49:48+00:00
2696
2367665
true
16x9
false
no

Largeeddy modeling for particleladen flow: turbulence modulation and intensified heat transfer by Bernard Geurts (Twente)
ucs_sms_2363417_2489518
http://sms.cam.ac.uk/media/2489518
Largeeddy modeling for particleladen flow: turbulence modulation and intensified heat transfer by Bernard Geurts (Twente)
Talk given by Prof Bernard Geurts (University of Twente) at Department of Engineering, University of Cambridge, 19 May 2017, as part of the CUED Fluids seminar series.
The talk discussed Large Eddy Simulation (LES) for turbulent particleladen flows, discussing subgrid modelling and the coupling of the discrete particle phase with the continuous flow model.
Tue, 30 May 2017 15:58:34 +0100
twophase flow,largeeddy simulation,particleladen flow,subgrid models,heat transfer,stochastic forcing,point particles
101
108
108100
101
101100
University of Cambridge
Bernard Geurts
1a3a391bef18b37ba1ef51700c442c78
766773e0e95a401c9b21e247a260a81c
57dc9d27cfab9c27311a30c70a79f5a8
d08e8c0a46fc13eb193b4aa3074f5bf6
6e742a2cf7fcb1bc1cf5adb630f19c60
60c06df30eafb746a8e2df12cf3cfb14
Talk given by Prof Bernard Geurts (University of Twente) at Department of...
Talk given by Prof Bernard Geurts (University of Twente) at Department of Engineering, University of Cambridge, 19 May 2017, as part of the CUED Fluids seminar series.
The talk discussed Large Eddy Simulation (LES) for turbulent particleladen flows, discussing subgrid modelling and the coupling of the discrete particle phase with the continuous flow model.
Cambridge University
3097
twophase flow,largeeddy simulation,particleladen flow,subgrid models,heat transfer,stochastic forcing,point particles
http://sms.cam.ac.uk/media/2489518
Largeeddy modeling for particleladen flow: turbulence modulation and intensified heat transfer by Bernard Geurts (Twente)
Talk given by Prof Bernard Geurts (University of Twente) at Department of Engineering, University of Cambridge, 19 May 2017, as part of the CUED Fluids seminar series.
The talk discussed Large Eddy Simulation (LES) for turbulent particleladen flows, discussing subgrid modelling and the coupling of the discrete particle phase with the continuous flow model.
Turbulent flow arises in a wide variety of natural and technological situations. While the full richness of turbulence is appreciated qualitatively, a quantitatively accurate prediction is often outside the scope of direct numerical computations. As an alternative, filtered flow descriptions, such as largeeddy simulation (LES), have been proposed and studied intensively, promising a combination of accuracy and computational feasibility. While LES is effective in reducing the dynamic complexity of a simulation, accuracy limitations are a matter of ongoing discussion. In this presentation, turbulent flow with embedded pointparticles will be reviewed, paying attention to the coupling of the discrete particle phase with the continuous flow model. Effects of phase transition will be included and contributions to the effectiveness of heat transfer will be quantified. Particular attention will be given to flows at high Reynolds numbers for which next to explicit subfilter modeling of the flow also stochastic forcing of the particle motion will be included.
20170530T15:58:34+01:00
3097
2489518
true
4x3
false
no

Linear stability vs. real nonlinear flow  Part 2 by Outi Tammisola (Nottingham)
ucs_sms_2363417_2363444
http://sms.cam.ac.uk/media/2363444
Linear stability vs. real nonlinear flow  Part 2 by Outi Tammisola (Nottingham)
Talk given by Dr Outi Tammisola (Faculty of Engineering, University of Nottingham) at Department of Engineering, University of Cambridge, 18 November 2016, as part of the CUED Fluids seminar series.
The talk discusses ways linear stability and sensitivity analysis can (and cannot) provide information about nonlinear flows. Two examples are considered: flow in a constricted pipe (stenotic flow) and swirling turbulent flow in a fuel injector geometry.
Mon, 21 Nov 2016 13:40:52 +0000
linear stability,nonlinear flow,stenotic flow,sensitivity analysis,fuel injector
101
108
108100
University of Cambridge
Outi Tammisola
c752a19b00dc493f18601500f2f40f56
b1794ac8c6b914db874ef2523656411e
d7bc48d84bd5fc062822f33c9f3130fb
226f8ddd6cb6aac25f839b4b1ef914e5
fc63e5b6f801dd38ff76a316f26c0852
702ef99f74eafc53db3b3872cc48db67
Talk given by Dr Outi Tammisola (Faculty of Engineering, University of...
Talk given by Dr Outi Tammisola (Faculty of Engineering, University of Nottingham) at Department of Engineering, University of Cambridge, 18 November 2016, as part of the CUED Fluids seminar series.
The talk discusses ways linear stability and sensitivity analysis can (and cannot) provide information about nonlinear flows. Two examples are considered: flow in a constricted pipe (stenotic flow) and swirling turbulent flow in a fuel injector geometry.
Cambridge University
2779
linear stability,nonlinear flow,stenotic flow,sensitivity analysis,fuel injector
http://sms.cam.ac.uk/media/2363444
Linear stability vs. real nonlinear flow  Part 2 by Outi Tammisola (Nottingham)
Talk given by Dr Outi Tammisola (Faculty of Engineering, University of Nottingham) at Department of Engineering, University of Cambridge, 18 November 2016, as part of the CUED Fluids seminar series.
The talk discusses ways linear stability and sensitivity analysis can (and cannot) provide information about nonlinear flows. Two examples are considered: flow in a constricted pipe (stenotic flow) and swirling turbulent flow in a fuel injector geometry.
My fluids talk two years ago had the following aim: 'to demonstrate successes and limitations of linear stability theory in assessing the nonlinear behavior of some real unstable flows in comparison to experiments and DNS '. The present talk can be seen as a continuation of this theme. We will look at flows which are more challenging to characterize, and I will present ways in which linear stability and sensitivity analysis can (and cannot) provide information about the flow. An example is the transition and rich nonlinear dynamics of the flow in a constricted pipe (stenotic flow), and its extreme sensitivity to asymmetry. Furthermore, we will see how a controversial mean flow stability analysis yields accurate eigenmodes and oscillation frequencies in a swirling turbulent flow in a fuel injector geometry. These eigenmodes can be used to perform sensitivity analysis. I will show how sensitivity analysis may identify which parts of the flow in a complex geometry need to be altered in order to change its hydrodynamic stability characteristics.
20170221T17:49:20+00:00
2779
2363444
true
16x9
false
no

Making waves in the core of the Earth by Oliver Bardsley (Cambridge)
ucs_sms_2363417_2503436
http://sms.cam.ac.uk/media/2503436
Making waves in the core of the Earth by Oliver Bardsley (Cambridge)
Talk given by Oliver Bardsley (CUED) at Department of Engineering, University of Cambridge, 26 May 2017, as part of the CUED Fluids seminar series.
The talk discusses wave motions in the Earth's outer core, focusing on properties of these waves that may encourage dynamo action.
Thu, 22 Jun 2017 17:21:23 +0100
MHD,geodynamo,alpha^2 dynamo,dispersive,anisotropic,ray tracing
109
109107
109
109108
University of Cambridge
Oliver Bardsley
d0926ef709e2852fbe29af0c0d58b279
d691bb5f0a3d0ff94608b081f642fcec
00c66b98ddb04972c9725e51d285a200
6fcfb8d28e87f8cbda86f61eb91b393e
21de658b0dbf4f95e5fa55eeb827ba63
a8789624f62979a8b57754e7eb338e65
Talk given by Oliver Bardsley (CUED) at Department of Engineering, University...
Talk given by Oliver Bardsley (CUED) at Department of Engineering, University of Cambridge, 26 May 2017, as part of the CUED Fluids seminar series.
The talk discusses wave motions in the Earth's outer core, focusing on properties of these waves that may encourage dynamo action.
Cambridge University
2945
MHD,geodynamo,alpha^2 dynamo,dispersive,anisotropic,ray tracing
http://sms.cam.ac.uk/media/2503436
Making waves in the core of the Earth by Oliver Bardsley (Cambridge)
Talk given by Oliver Bardsley (CUED) at Department of Engineering, University of Cambridge, 26 May 2017, as part of the CUED Fluids seminar series.
The talk discusses wave motions in the Earth's outer core, focusing on properties of these waves that may encourage dynamo action.
I make the claim that the outer core of the Earth, a rapidlyrotating, electricallyconducting ocean vigorously stirred by convective upwellings, is a breeding ground for a diverse zoo of wave motions. These are highly dispersive (since propagation velocity depends on wavelength), anisotropic (due to the rotation axis and local magnetic field direction), caustical (or “selffocussing”), heterogeneous (due to a spatiallyvarying field), dissipative (owing to the field’s diffusive nature), and nonlinear (necessarily, if they are to alter field topology). I address all but one of these peculiarities, unearthing some interesting phenomena along the way, and perhaps opening a small window onto planetary core dynamics – specifically the mechanisms which may encourage dynamo action.
20170622T17:21:23+01:00
2945
2503436
true
4x3
false
no

Reentry vehicles for 21st century space missions by Paul Bruce (ICL)
ucs_sms_2363417_2782804
http://sms.cam.ac.uk/media/2782804
Reentry vehicles for 21st century space missions by Paul Bruce (ICL)
Talk given by Dr Paul Bruce (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 8 June 2018, as part of the CUED Fluids seminar series.
The talk describes ongoing work at Imperial College, London to develop reducedorder models of atmospheric entry, that could be applied in particular to landing a manned vehicle on Mars.
Thu, 05 Jul 2018 16:32:12 +0100
Atmospheric entry,Mars mission,Ballistic coefficient,Supersonic parachute,Heat shield
101
101105
109
109101
University of Cambridge
Dr Paul Bruce
0a912d34f658921beaf0db97ea472236
a327bd4c60ea42c16f8dc113383d3a75
569fea76897a191843f3b3d7be712a5a
5df514556062282a0c8337c773186f3d
4336aecbf759b4fccd7272c9a8c05fea
ed0ff5bd57bd1e44d7d461a34b419aa9
Talk given by Dr Paul Bruce (Department of Aeronautics, Imperial College,...
Talk given by Dr Paul Bruce (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 8 June 2018, as part of the CUED Fluids seminar series.
The talk describes ongoing work at Imperial College, London to develop reducedorder models of atmospheric entry, that could be applied in particular to landing a manned vehicle on Mars.
Cambridge University
3297
Atmospheric entry,Mars mission,Ballistic coefficient,Supersonic parachute,Heat shield
http://sms.cam.ac.uk/media/2782804
Reentry vehicles for 21st century space missions by Paul Bruce (ICL)
Talk given by Dr Paul Bruce (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 8 June 2018, as part of the CUED Fluids seminar series.
The talk describes ongoing work at Imperial College, London to develop reducedorder models of atmospheric entry, that could be applied in particular to landing a manned vehicle on Mars.
Entering a planet's atmosphere from space and landing safely on its surface is a significant engineering challenge. For more than 60 years, engineers have tackled this problem; developing atmospheric entry vehicles with an impressive track record of returning cargo and humans to Earth, and even sending (unmanned) missions to land on the surface of Mars. However, as our aspirations and ambition for exploring space grow, mission requirements are evolving beyond the capabilities of existing triedandtested hardware and a new generation of atmospheric entry vehicles is required.
In this seminar, I will present the results from an ongoing project at Imperial to tackle some of the challenges of landing humans safely on the surface of Mars. The work centres on the development of a reducedorder model to capture the unique aeroelastic behaviour of this new class of vehicle as it negotiates the reentry environment. I will try to provide answers to the following questions:
 How do we model atmospheric entry?
 Why is landing humans on Mars so difficult?
 What are the most promising candidate technologies for doing so?
 How do we design optimal large diameter aerodecelerator heat shields?
 Why do we need a coupled aerostructural solver?
 Are there potential benefits from designing flexible spacecraft?
My goal in this talk is not to bamboozle with equations and complex graphs, but to provide some insight into the engineering challenges of future interplanetary exploration missions and, ultimately, explain why we believe this warrants a new approach to spacecraft design and how we are working towards this goal at Imperial.
20180705T16:32:13+01:00
3297
2782804
true
4x3
false
no

Secrets learned from the peregrine falcon diving flight by Christoph Bruecker (City)
ucs_sms_2363417_2424744
http://sms.cam.ac.uk/media/2424744
Secrets learned from the peregrine falcon diving flight by Christoph Bruecker (City)
Talk given by Prof Christoph Bruecker (School of Mathematics, Computer Science and Engineering, City University, London) at Department of Engineering, University of Cambridge, 14 February 2017, as part of the CUED Fluids seminar series.
The peregine falcon is the fastest animal in the world which can reach 200mph during its stoop. The aerodynamics of this highspeed manoeuvre and its control in such flight conditions is investigated and discussed during the talk. Life studies in the field as well as experimental flow studies in the wind tunnel and CFD simulations helped to discover some of the features of the birds flight.
Thu, 23 Feb 2017 16:18:32 +0000
Bird flight,Aerodynamics,Stoop,Feathers,Vortices,Trefftz plane flow
101
109
109103
University of Cambridge
Christoph Bruecker
1562ed6b435e98d91f09d13b23431ca9
6b15aa3198396ecce701d9e87764962c
ca3611d3b166d12b8ff52aadb2adc6ec
98cd681da8247b5ceae675941eba736e
52fe63037797b5db0d6f043d7d8672c0
5d8d69307d78a13bfd0921f5d52102d5
Talk given by Prof Christoph Bruecker (School of Mathematics, Computer Science...
Talk given by Prof Christoph Bruecker (School of Mathematics, Computer Science and Engineering, City University, London) at Department of Engineering, University of Cambridge, 14 February 2017, as part of the CUED Fluids seminar series.
The peregine falcon is the fastest animal in the world which can reach 200mph during its stoop. The aerodynamics of this highspeed manoeuvre and its control in such flight conditions is investigated and discussed during the talk. Life studies in the field as well as experimental flow studies in the wind tunnel and CFD simulations helped to discover some of the features of the birds flight.
Cambridge University
3228
Bird flight,Aerodynamics,Stoop,Feathers,Vortices,Trefftz plane flow
http://sms.cam.ac.uk/media/2424744
Secrets learned from the peregrine falcon diving flight by Christoph Bruecker (City)
Talk given by Prof Christoph Bruecker (School of Mathematics, Computer Science and Engineering, City University, London) at Department of Engineering, University of Cambridge, 14 February 2017, as part of the CUED Fluids seminar series.
The peregine falcon is the fastest animal in the world which can reach 200mph during its stoop. The aerodynamics of this highspeed manoeuvre and its control in such flight conditions is investigated and discussed during the talk. Life studies in the field as well as experimental flow studies in the wind tunnel and CFD simulations helped to discover some of the features of the birds flight.
20170223T16:18:33+00:00
3228
2424744
true
4x3
false
no

The largescale structure of smallscale turbulence, some implications for dispersion by Gerrit Elsinga (TU Delft)
ucs_sms_2363417_3021913
http://sms.cam.ac.uk/media/3021913
The largescale structure of smallscale turbulence, some implications for dispersion by Gerrit Elsinga (TU Delft)
Thu, 11 Jul 2019 12:12:06 +0100
University of Cambridge
Dr Gerrit Elsinga
d2418643fb3918088a5e2c3a5c3babaa
97252647ac279f1702ca8ff99ee8a065
80a5656c63d842e64446934051aa9262
45d1d4394ffc7c2bc5e211a4181b7f30
c188e65706b9e119ffeffd21d3a5bcc5
47a392b3eba2a3ca556fcc19ae76a6da
Cambridge University
2174
http://sms.cam.ac.uk/media/3021913
The largescale structure of smallscale turbulence, some implications for dispersion by Gerrit Elsinga (TU Delft)
Turbulence is omnipresent in flows of engineering and environmental interest, and is well known to contribute significantly to, for example, scalar dispersion and skin friction. When modelling the effects of turbulence, it is typically assumed that the smallscale motions are largely independent of the large scales of turbulent motion. However, there is increasing evidence to suggest that this simplification is invalid and the source of major inaccuracy in existing models and scaling laws.
The talk discusses recent advances in the understanding of the spatial structure of the smallscale motions in turbulence. Most importantly, their organisation into shear layers introduces a dependence on the large, energetic motions bounding the layers, which are furthermore flow dependent. These insights allow to clearly identify shortcomings in certain turbulence models and propose direction for improvements. Moreover, these findings call into question basic scaling laws for turbulent dispersion.
20190725T15:48:50+01:00
2174
3021913
true
4x3
false
no

The Rapid Optimization Library by Greg von Winckel (Sandia National Laboratories)
ucs_sms_2363417_2647541
http://sms.cam.ac.uk/media/2647541
The Rapid Optimization Library by Greg von Winckel (Sandia National Laboratories)
Talk given by Greg von Winckel (Center for Computing Research, Sandia National Laboratories) at Department of Engineering, University of Cambridge, 3 November 2017, as part of the CUED Fluids seminar series.
Wed, 17 Jan 2018 08:56:14 +0000
University of Cambridge
Greg von Winckel
99197fd58167fef265bcf6a5ad2f5855
4c1c63a243048b5ab3578f421832a768
751d3e8058cf8d82f6310e0c5d10769c
0d820b4320755ab9aabc63bc25185e3c
44e941a3d905ed9b51bd77980cfca152
b794868e653ea6d1cd209efc80eab352
Talk given by Greg von Winckel (Center for Computing Research, Sandia National...
Talk given by Greg von Winckel (Center for Computing Research, Sandia National Laboratories) at Department of Engineering, University of Cambridge, 3 November 2017, as part of the CUED Fluids seminar series.
Cambridge University
3321
http://sms.cam.ac.uk/media/2647541
The Rapid Optimization Library by Greg von Winckel (Sandia National Laboratories)
Talk given by Greg von Winckel (Center for Computing Research, Sandia National Laboratories) at Department of Engineering, University of Cambridge, 3 November 2017, as part of the CUED Fluids seminar series.
20180117T08:56:15+00:00
3321
2647541
true
4x3
false
no

Timescales and the inertial subrange in wall flows by Jonathan Morrison (ICL)
ucs_sms_2363417_2476384
http://sms.cam.ac.uk/media/2476384
Timescales and the inertial subrange in wall flows by Jonathan Morrison (ICL)
Talk given by Prof Jonathan Morrison (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 28 April 2017, as part of the CUED Fluids seminar series.
The talk describes analysis of experiments for fullydeveloped turbulent pipe flow and in a rapidlydistorted boundary layer to reveal how the timescales governing the development of the shear layers play an important role in the analysis. The issue of equilibrium in turbulence is also discussed.
Tue, 09 May 2017 17:17:45 +0100
turbulent timescales,turbulence equilibrium,rapidlydistorted,boundary layer,turbulent pipe flow,shear layer,inertial subrange
101
101105
University of Cambridge
Prof Jonathan Morrison
f50d2e73e142659c35d4d179ad4a547d
f08aef63530d7444c5157892d0b3c308
4f283e2b786a960e6a53f8174b5837bf
d2366fd167a4e26666c2ed3940abde1c
ca9fff363fb331ae5bea9c67f4612ab6
edab04d7513b49f79e6250a99bf970db
Talk given by Prof Jonathan Morrison (Department of Aeronautics, Imperial...
Talk given by Prof Jonathan Morrison (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 28 April 2017, as part of the CUED Fluids seminar series.
The talk describes analysis of experiments for fullydeveloped turbulent pipe flow and in a rapidlydistorted boundary layer to reveal how the timescales governing the development of the shear layers play an important role in the analysis. The issue of equilibrium in turbulence is also discussed.
Cambridge University
3960
turbulent timescales,turbulence equilibrium,rapidlydistorted,boundary layer,turbulent pipe flow,shear layer,inertial subrange
http://sms.cam.ac.uk/media/2476384
Timescales and the inertial subrange in wall flows by Jonathan Morrison (ICL)
Talk given by Prof Jonathan Morrison (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 28 April 2017, as part of the CUED Fluids seminar series.
The talk describes analysis of experiments for fullydeveloped turbulent pipe flow and in a rapidlydistorted boundary layer to reveal how the timescales governing the development of the shear layers play an important role in the analysis. The issue of equilibrium in turbulence is also discussed.
The scaling of NSTAP probe data from the Princeton superpipe is examined and compared to both K41 and K62 theories for the inertial subrange. The comparisons are made at the pipe centreline and in the logarithmic region, where in both cases, the transport equation for the turbulence kinetic energy is really quite simple. Nonetheless, single hotwire data (resolved to less than three Kolmogorov lengthscales) for the streamwise velocity fluctuations show very little agreement with Kolmogorov's theories at lambdabased Reynolds numbers of several hundred. Reasons for this are put forward and used to introduce a novel experiment in which freestream turbulence, initially passing over a moving ground plane to produce a shearless boundary layer, is rapidly sheared on passing to a stationary surface. Such an arrangement is well suited to examining "topdown" and "bottomup" transport mechanisms in a systematic manner. Here we focus on the linear (fast) and nonlinear (slow) contributions to static pressure fluctuations, both instream and at the wall.
20170509T17:17:45+01:00
3960
2476384
true
4x3
false
no

Turbulence, Periodic Orbits and Koopman Analysis by Rich Kerswell (DAMTP, Cambridge)
ucs_sms_2363417_3021851
http://sms.cam.ac.uk/media/3021851
Turbulence, Periodic Orbits and Koopman Analysis by Rich Kerswell (DAMTP, Cambridge)
Thu, 11 Jul 2019 12:03:33 +0100
University of Cambridge
Prof Rich Kerswell
26390156c950a477b50aa9a02170a001
9f50288654e14674bdf7f12fa30b4d13
1344593ceb72a7b487952bf96e30798a
f719dc33f3dda8a9b748b49386328749
0aea1d0abf646f4ceeb195689bdcd66c
77dcef9948567fb150ba3b5c9069568f
Cambridge University
3193
http://sms.cam.ac.uk/media/3021851
Turbulence, Periodic Orbits and Koopman Analysis by Rich Kerswell (DAMTP, Cambridge)
Abstract not available
20190725T15:49:26+01:00
3193
3021851
true
4x3
false
no

Turbulent flows over canopies by Akshath Sharma (Cambridge)
ucs_sms_2363417_2770315
http://sms.cam.ac.uk/media/2770315
Turbulent flows over canopies by Akshath Sharma (Cambridge)
Talk given by Akshath Sharma (Department of Engineering, University of Cambridge) at CUED, 25 May 2018, as part of the CUED Fluids seminar series.
The talk discusses the question of optimum canopies, as related to the prevalence of KelvinHelmholtzlike instabilities over them, using a combination of relatively simple models for dense canopies and DNS simulations for sparse canopies.
Wed, 13 Jun 2018 16:33:19 +0100
canopy flow,instabilities,Direct Numerical Simulation,optimum canopy
101
101104
109
109109
109
109100
109
109103
University of Cambridge
Mr Akshath Sharma
09c428f44ac098e72a9d27425cd821bf
f6d13ea0b2c62730b1c4cd6438d58db2
2a46680a6b1e67a56fd9428d1b0f926c
be8ac8884b650b339e798070a3fb2487
f9db147959e8929b09cc20bcc2f370a9
e7770dc020b243f9749588b69461bb91
Talk given by Akshath Sharma (Department of Engineering, University of...
Talk given by Akshath Sharma (Department of Engineering, University of Cambridge) at CUED, 25 May 2018, as part of the CUED Fluids seminar series.
The talk discusses the question of optimum canopies, as related to the prevalence of KelvinHelmholtzlike instabilities over them, using a combination of relatively simple models for dense canopies and DNS simulations for sparse canopies.
Cambridge University
2476
canopy flow,instabilities,Direct Numerical Simulation,optimum canopy
http://sms.cam.ac.uk/media/2770315
Turbulent flows over canopies by Akshath Sharma (Cambridge)
Talk given by Akshath Sharma (Department of Engineering, University of Cambridge) at CUED, 25 May 2018, as part of the CUED Fluids seminar series.
The talk discusses the question of optimum canopies, as related to the prevalence of KelvinHelmholtzlike instabilities over them, using a combination of relatively simple models for dense canopies and DNS simulations for sparse canopies.
Canopies are pervasive in the environment, whether it be forests, crops or clusters of buildings. However, numerous fundamental questions regarding the characteristics of flows inside and over canopies still remain unanswered. Understanding these flows would have applications in energy harvesting, increasing mixing and heat transfer, or even reducing crop losses due to wind damage. In this presentation, we explore whether canopy properties can be tuned to exploit the flow over them. First, we will use simple models for flows through canopies to explore the effect of canopy properties on the formation of KelvinHelmholtzlike instabilities over them. These models reveal some optimum canopies which result in the formation of strong instabilities. As we increase the sparsity of the canopy, the simplified models fail to capture the flow within it. For this regime, we will present the results obtained from Direct Numerical Simulations of the flow.
20180613T16:33:19+01:00
2476
2770315
true
4x3
false
no

Turbulent flows over superhydrophobic surfaces by Chris Fairhall (Cambridge)
ucs_sms_2363417_2678540
http://sms.cam.ac.uk/media/2678540
Turbulent flows over superhydrophobic surfaces by Chris Fairhall (Cambridge)
Talk given by Chris Fairhall (CUED) at Department of Engineering, University of Cambridge, 23 February 2018, as part of the CUED Fluids seminar series.
The talk focuses on superhydrophobic surfaces and their ability to reduce drag in turbulent flows, in particular the role played by slip and roughness in this process.
Tue, 27 Feb 2018 14:49:23 +0000
Superhydrophobic surface,Drag reduction,Surface roughness,Slip
101
101
101105
109
109108
University of Cambridge
Chris Fairhall
7402621bcab8cc4aa083da0aa340d133
bf52cda70b406226c3e2eafea858b777
cda8043bc170ce6a4be904b4e922c0d1
e635643d1a3bdf105585dab9ea675fd4
03cebbbd13979332bb28c755bbaf9a0e
4ecd3f08ba4addc9039318c3b2a6551b
Talk given by Chris Fairhall (CUED) at Department of Engineering, University of...
Talk given by Chris Fairhall (CUED) at Department of Engineering, University of Cambridge, 23 February 2018, as part of the CUED Fluids seminar series.
The talk focuses on superhydrophobic surfaces and their ability to reduce drag in turbulent flows, in particular the role played by slip and roughness in this process.
Cambridge University
1999
Superhydrophobic surface,Drag reduction,Surface roughness,Slip
http://sms.cam.ac.uk/media/2678540
Turbulent flows over superhydrophobic surfaces by Chris Fairhall (Cambridge)
Talk given by Chris Fairhall (CUED) at Department of Engineering, University of Cambridge, 23 February 2018, as part of the CUED Fluids seminar series.
The talk focuses on superhydrophobic surfaces and their ability to reduce drag in turbulent flows, in particular the role played by slip and roughness in this process.
In the quest for drag reduction, superhydrophobic surfaces have recently attracted a growing interest. These superhydrophobic surfaces are rough surfaces that have the ability to entrap pockets of gas on the surface, essentially allowing the overlying flow to slip over the surface, resulting in a drag reduction. This talk will discuss the common drag reduction mechanism that allows surfaces (e.g. superhydrophobic surfaces, riblets, permeable media) to reduce drag in turbulent flows, and how drag reduction can be explained by a simple model. Then we will focus on isolating the effects that slip and roughness have on the overlying turbulence of superhydrophobic surfaces.
20180228T15:06:50+00:00
1999
2678540
true
4x3
false
no

Unsteady hydrodynamics in 3D by Amanda Smyth (Cambridge)
ucs_sms_2363417_3104494
http://sms.cam.ac.uk/media/3104494
Unsteady hydrodynamics in 3D by Amanda Smyth (Cambridge)
Talk given by Dr Amanda Smyth (Whittle Laboratory, University of Cambridge) at Department of Engineering, University of Cambridge, 25 October 2019, as part of the CUED Fluids seminar series.
Thu, 21 Nov 2019 08:51:18 +0000
University of Cambridge
Dr Amanda Smyth
4683414c1094d3de26985d3ec1c299d0
ef3a8b519c71c31605eced6ce9726815
7b107b78cda165a7adee98a3c23ddc21
74b2f119d6dbae7dfc47665269fb5cff
393beb4b1d4cd59d17dbc93125c19221
249166f75a54bdcbdc0d56dec9a557d9
Talk given by Dr Amanda Smyth (Whittle Laboratory, University of Cambridge) at...
Talk given by Dr Amanda Smyth (Whittle Laboratory, University of Cambridge) at Department of Engineering, University of Cambridge, 25 October 2019, as part of the CUED Fluids seminar series.
Cambridge University
2744
http://sms.cam.ac.uk/media/3104494
Unsteady hydrodynamics in 3D by Amanda Smyth (Cambridge)
Talk given by Dr Amanda Smyth (Whittle Laboratory, University of Cambridge) at Department of Engineering, University of Cambridge, 25 October 2019, as part of the CUED Fluids seminar series.
Tidal power has huge potential as a source of predictable renewable energy in the UK, but the harsh operating environment increases the costs of manufacture and maintenance, and reduces the reliability of the resource. This talk will focus on the damage to tidal turbines caused by surface waves and ocean turbulence.
A number of recent studies have shown that the loworder models used to predict turbine load response to turbulence and waves are not capable of reproducing experimental results, even for very simple unsteady forcing. In this talk I will show that the cause of this discrepancy is that the models are based on 2D striptheory, and also show how 3D effects impact the unsteady hydrodynamics. From this we can find the limits of applicability of 2D striptheory models on 3D blade geometries. We will also look at the consequences of 3D unsteady flow effects on turbine modelling and fatigue life.
20191121T08:51:18+00:00
2744
3104494
true
4x3
false
no

Unsteady turbulence cascades by Christos Vassilicos (ICL)
ucs_sms_2363417_2401483
http://sms.cam.ac.uk/media/2401483
Unsteady turbulence cascades by Christos Vassilicos (ICL)
Talk given by Prof Christos Vassilicos (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 20 January 2017, as part of the CUED Fluids seminar series.
The talk discusses new perspectives on turbulent energy transfer, in particular, turbulence dissipation scalings, which recent work suggests are related to unsteady interscale energy transfer processes. The consequences for some important turbulent flows are described.
Mon, 23 Jan 2017 12:08:49 +0000
turbulence energy transfer,turbulence dissipation scaling,unsteady interscale energy transfer,turbulent wake,turbulent jet,entrainment
101
108
108100
University of Cambridge
Christos Vassilicos
388c86356be10086ebbbac220e539ae1
60f4c0322cb8cde3c72a85ed17eb848f
6bfdd524932ffaecb4b817f180407a8a
fa6280e03bf1504cfcce1c80a60d8c20
ee367558991dd551701448973fae6a2d
88ef7d27158941effe085b6b39073fd3
Talk given by Prof Christos Vassilicos (Department of Aeronautics, Imperial...
Talk given by Prof Christos Vassilicos (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 20 January 2017, as part of the CUED Fluids seminar series.
The talk discusses new perspectives on turbulent energy transfer, in particular, turbulence dissipation scalings, which recent work suggests are related to unsteady interscale energy transfer processes. The consequences for some important turbulent flows are described.
Cambridge University
2909
turbulence energy transfer,turbulence dissipation scaling,unsteady interscale energy transfer,turbulent wake,turbulent jet,entrainment
http://sms.cam.ac.uk/media/2401483
Unsteady turbulence cascades by Christos Vassilicos (ICL)
Talk given by Prof Christos Vassilicos (Department of Aeronautics, Imperial College, London) at Department of Engineering, University of Cambridge, 20 January 2017, as part of the CUED Fluids seminar series.
The talk discusses new perspectives on turbulent energy transfer, in particular, turbulence dissipation scalings, which recent work suggests are related to unsteady interscale energy transfer processes. The consequences for some important turbulent flows are described.
Turbulence energy transfer through scales is arguably one of the most central and important processes in turbulent flows. Much of turbulence theory and modelling over the past 70 years has been based on the Kolmogorov (1941) stationary cascade which implies a particular wellknown scaling of the turbulence dissipation rate. However, accumulating evidence from laboratory experiments and, more recently, numerical simulations is pointing at a very different turbulence dissipation scaling in important regions of various turbulent flows. There are consequences for boundaryfree turbulent shear flows such as selfsimilar turbulent wakes and jets because their growth rates are closely linked to the centreline turbulence dissipation scaling. These consequences include new turbulent mean flow scalings with streamwise distance, and consequences concerning entrainment through the turbulent/nonturbulent interface. Direct Numerical Simulations of unsteady periodic turbulence suggest that the turbulence dissipation scalings are related to unsteady interscale energy transfer processes. Different dissipation scalings result from different types of unsteady interscale energy transfers.
20170221T17:48:23+00:00
2909
2401483
true
4x3
false
no

UpsideDown and InsideOut: The Biomechanics of Cell Sheet Folding by Ray Goldstein (DAMTP, Cambridge)
ucs_sms_2363417_2906662
http://sms.cam.ac.uk/media/2906662
UpsideDown and InsideOut: The Biomechanics of Cell Sheet Folding by Ray Goldstein (DAMTP, Cambridge)
Talk given by Prof Ray Goldstein (Department of Applied Mathematics and Theoretical Physics, University of Cambridge) at Department of Engineering, University of Cambridge, 18 January 2019, as part of the CUED Fluids seminar series.
The talk discusses deformations of cell sheets, illustrated using one of the simplest examples of cell sheet folding, the 'inversion' of the algal genus Volvox.
Wed, 23 Jan 2019 16:25:42 +0000
biomechanics,cell sheet folding,Volvox,inversion,in vivo visualization,cell shape changes,algae
108
108100
109
109103
109
109108
109
109105
University of Cambridge
Prof Raymond Goldstein
a28672d0003bf010c27252c93eff6d95
cd948c0cd926b625b3cd80d299e40fab
33218ea95acf24ae83255728195c6830
f5bba6278fda6a21779178a2cc1f12af
78c25cbf274ab5e8392ac64e799d7504
c692a074670743e35a71bfc497cd8f1a
Talk given by Prof Ray Goldstein (Department of Applied Mathematics and...
Talk given by Prof Ray Goldstein (Department of Applied Mathematics and Theoretical Physics, University of Cambridge) at Department of Engineering, University of Cambridge, 18 January 2019, as part of the CUED Fluids seminar series.
The talk discusses deformations of cell sheets, illustrated using one of the simplest examples of cell sheet folding, the 'inversion' of the algal genus Volvox.
Cambridge University
3005
biomechanics,cell sheet folding,Volvox,inversion,in vivo visualization,cell shape changes,algae
http://sms.cam.ac.uk/media/2906662
UpsideDown and InsideOut: The Biomechanics of Cell Sheet Folding by Ray Goldstein (DAMTP, Cambridge)
Talk given by Prof Ray Goldstein (Department of Applied Mathematics and Theoretical Physics, University of Cambridge) at Department of Engineering, University of Cambridge, 18 January 2019, as part of the CUED Fluids seminar series.
The talk discusses deformations of cell sheets, illustrated using one of the simplest examples of cell sheet folding, the 'inversion' of the algal genus Volvox.
Deformations of cell sheets are ubiquitous in early animal development, often arising from a complex and poorly understood interplay of cell shape changes, division, and migration. I will describe our work on perhaps the simplest example of cell sheet folding: the “inversion” process of the algal genus Volvox, during which spherical embryos turn themselves inside out through a process hypothesized to arise from cell shape changes alone. We have used light sheet microscopy to obtain the first threedimensional visualizations of inversion in vivo, and developed the first theory of this process, in which cell shape changes appear as local variations of intrinsic curvature, contraction and stretching of an elastic shell. Our results support a scenario in which these active processes function in a defined spatiotemporal manner to enable inversion.
20190123T16:25:42+00:00
3005
2906662
true
4x3
false
no

Vibrating cables & flapping flags: classical fluidsolid instabilities or energy sources by Sébastien Michelin (École Polytechnique)
ucs_sms_2363417_2476812
http://sms.cam.ac.uk/media/2476812
Vibrating cables & flapping flags: classical fluidsolid instabilities or energy sources by Sébastien Michelin (École Polytechnique)
Talk given by Prof Sébastien Michelin (LadHyX, École Polytechnique) at Department of Engineering, University of Cambridge, 9 May 2017, as part of the CUED Fluids seminar series.
The talk reconsiders two classical fluidstructure interaction problems  vortexinduced vibration of flexible cables and flapping flexible flags  from the aim of exploiting the induced motion to harvest energy rather than with the traditional aim of reducing or eliminating these motions.
Wed, 10 May 2017 10:51:20 +0100
fluidstructure interaction,vortexinduced vibration,flapping flag,energy harvesting,flexible cable
101
101104
109
109109
108
108100
University of Cambridge
Sébastien Michelin
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4dba14e067adcd00a5935096916c5e65
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Talk given by Prof Sébastien Michelin (LadHyX, École Polytechnique) at...
Talk given by Prof Sébastien Michelin (LadHyX, École Polytechnique) at Department of Engineering, University of Cambridge, 9 May 2017, as part of the CUED Fluids seminar series.
The talk reconsiders two classical fluidstructure interaction problems  vortexinduced vibration of flexible cables and flapping flexible flags  from the aim of exploiting the induced motion to harvest energy rather than with the traditional aim of reducing or eliminating these motions.
Cambridge University
3840
fluidstructure interaction,vortexinduced vibration,flapping flag,energy harvesting,flexible cable
http://sms.cam.ac.uk/media/2476812
Vibrating cables & flapping flags: classical fluidsolid instabilities or energy sources by Sébastien Michelin (École Polytechnique)
Talk given by Prof Sébastien Michelin (LadHyX, École Polytechnique) at Department of Engineering, University of Cambridge, 9 May 2017, as part of the CUED Fluids seminar series.
The talk reconsiders two classical fluidstructure interaction problems  vortexinduced vibration of flexible cables and flapping flexible flags  from the aim of exploiting the induced motion to harvest energy rather than with the traditional aim of reducing or eliminating these motions.
The coupling of engineering structures with the wind or water currents flowing around them can generate socalled flowinduced vibrations, resulting in periodic and often large solid displacements and deformations. Until recently, such vibrations have been mostly studied from a control or stability point of view, to avoid or mitigate the resulting structural damage and fatigue. Yet recently, a new light is being shed on such fluidsolid interactions (FSI) as potential energy harvesting mechanisms to exploit the underlying energy transfer to power a generator. Here, we will present some of our recent work on two classical FSI problems (vortexinduced vibration of flexible cables and flapping flexible flags) as energy harvesting systems, highlighting fundamental principles regarding the efficiency of such systems and their optimisation.
20170510T10:51:20+01:00
3840
2476812
true
4x3
false
no
2363417