Dr Steve Cochard

PhD in Fluid Mechanics (EPFL), M.Sc. in Mechanical Engineering (EPFL)
Lecturer


School of Civil Engineering, Room 341
Phone: +61 2 9351 3208
Fax: +61 2 9351 3343
Email:

About Steve

Steve has just joined the Fluid and Environmental Group at the School of Civil Engineering after holding a Postdoc position in the Complex Fluids Laboratory at the University of British Columbia. His research has focused on the design, the development and the validation of a PIV system to provide an accurate measurement of the velocity field inside transient free-surface flow of viscoplastic materials.

His Ph.D. thesis entitled `Measurements of Time-Dependent free-surface Viscoplastic flows Down Steep Slopes' was completed under the supervision of Pr. C. Ancey at the Environmental Hydraulic Laboratory at EPFL. A novel fringe projection system was developed to provid accurate instantaneous whole-field 3D shape measurements of the free-surface profile and the spreading rate of non-Newtonian fluids at high repetition rate.

Before joining the Environmental Hydraulic Laboratory Steve had been working for more than four years in industry as an aero-thermodynamics engineer. There he had been associated with multidisciplinary projects with state-of-the art technology and competences. At first he joined for one year the Research and Technology Department of SNCF (Société Nationale des Chemins de Fer, French National Railway Company) in Paris, France as an internship for my master thesis and then as a consultant on the implementation of solutions to problems related to the complex and hazardous side-wind effect of the new TGV line Paris-Marseille. Some of the key duties were the implementation of a network of weather stations, the development of new algorithms to post-treat wind data and to detect and predict in real time the apparition of dangerous wind conditions that are used to adapt the kinematics of trains to avoid accidents. Later, he joined the Tunnel Ventilation Group at Electrowatt Infra AG in Zürich as a Projet Engineer, where he was a project leader for the development and improvement of ventilation systems on several existing tunnels or tunnel projects in particular in case of accidents leading to hazardous situations for people caught inside the tunnels. He was in charge of the development of numerical tools to simulate smoke, toxic gases and temperature propagation in case of fire in any underground facility with different ventilation configurations and he additionally supervised all the wind-tunnel tests realized for the new Bangkok metro line.

Since graduating, Steve has been involved on both numerical and experimental projects. He particularly enjoys developing new measurement techniques.

Research interests & current/recent research projects

• Wind Technology
  Wind load on structure
  Aerodynamics of structures
  Pollutant dispersion in urban environments
  Fire spreading and fire safety in urban environments
  Pedestrian wind comfort
  Wind energy
  Aerodynamic design of buildings
• Measurement techniques and facilities
  PIV (Particle Image Velocimetry)
  PTV (Particle Tracking Velocimetry)
  3D-PIV and 3D-PTV
  LDA (Laser Doppler Anemometry)
  PLIF (Planar Laser-Induced Fluorescence)
  Wind tunnel
  Towing tank
• Gravity driven flows
  Snow avalanches
  Debris flows
  Dam break
• Ground vehicle aerodynamics
  Aerodynamics of trains
  Aerodynamics of road vehicles
  Aerodynamics of sailing yachts

Publications

• C. Ancey, S. Cochard and N. Andreini : The dam-break problem for viscous fluids in the high-capillary-number limit, Journal of Fluid Mechanics, 2009.
• S. Cochard and C. Ancey : Experimental investigation of the spreading of viscoplastic fuids on inclined planes, Journal of Non-Newtonian Fluid Mechanics, 2008.
• S. Cochard, C. Ancey : Tracking the free surface of time-dependent flows : Image processing for the dam-break problem, Experiments in Fluids, 2008.
• C. Ancey and S. Cochard : The dam-break problem for Herschel-Bulkley fluids down steep flumes, Journal of Non-Newtonian Fluid Mechanics, 2008.
• N. Dubash, N.J. Balmforth, A. Slim and S. Cochard : What is the final shape of a viscoplastic slump ?, Journal of Non-Newtonian Fluid Mechanics, 2008.
• C. Ancey, S. Cochard, S. Wiederseiner and M. Rentschler : Existence and features of similarity solutions for non-Boussinesq gravity currents, Physica D, 2007.
• C. Ancey, S. Cochard, S. Wiederseiner and M. Rentschler : Front dynamics of supercritical non-Boussinesq gravity currents, Water Resources Research, 42, W08424, 2006.
• C. Ancey, S. Cochard : Understanding avalanches, Physics World, Vol 16 No 7, 2006
• S. Cochard, C. Ancey : Accurate measurements of free-surface in the dam-break problem, River Flow Conference, IHAR, Lisbonne, Portugal, September 2006.
• C. Ancey, S. Cochard, S. Wiederseiner and M. Rentschler : Front dynamics of a water surge at high Reynolds number : similarity solutions to the Saint-Venant equations, River Flow Conference, IHAR, Lisbonne, Portugal, September 2006.
• C. Ancey, P. Vollmoeller, S. Cochard : Rhéophysique des suspensions concentrées : cadre théorique et similitude, Congrès Français de Mécanique, Troyes, 2005.
• S. Cochard : Validation of the freeware ‘Fire Dynamics Simulator Version 2.0’ for simulating tunnel fires, Tunnel Management International, Vol. 6, Issue 4, 2003.
• J. Day, S. Cochard : Swiss Tunnels : The new design guidelines and how they are being implemented, Second International Conference on Road Tunnel Traffic and Safety. Hamburg, Germany, May 2003.
• S. Cochard : Validation of the freeware ‘Fire Dynamics Simulator Version 2.0’ for simulating tunnel fires, Fourth International Conference on Tunnel Fires, Basel, Switzerland, December 2002.

Teaching and Learning

• CIVL3612 Environmental & Fluids Eng: Viscous Flow

School & University Service

• TBA

Professional Service and Memberships

• TBA