Selection of results obtained in term 1997/1998

Supersonic vehicle (Alexandre Castellini):
The configuration of a car running at supersonic speed on a solid ground is a challenging task. The freestream Mach number is 1.02 and thus just above the sonic barrier which results in a shock wave below the vehicle which bounds between the ground and the vehicle. The 2-D simulation of course does not allow to model the wheels ! Several approximations to the geometry were necessary, especially the correct design of the rear part has shown to be difficult.

Velocity vectors colored by the Mach number.

Computational grid composed of triangles

Interaction of boat sails (Olivier Beon and Olivier Rocher):
In this study the interaction of the foc and the main sail of racing sailing boat is investigated. The freestream Mach number is 0.1 which corresponds to a fairly high speed of around 30 m/s or 50 Kns ! However, simulations at lower Mach numbers would be in the range of incompressible flows and hence not realistic with AVBP. This parametric study allowed to study the influence between the two sails, the influence of the sail inclination and the flow detachment on the sail surface. The profiles of the sails were approximated the modified NACA0012 profiles !

Interaction of wing profiles (Guillaume Galateau):
In the project the influence of the main profile on the flow past the tail stabilizer is investigated. Two NACA0012 profiles are scaled in size and rotated in order to do a qualitative parametrical study on the flow field depending on their relative position and inclination.

Mach number shading for freestream Mach=0.85 and 8 degrees incidence for both main wing and tail.

Left figure: total velocity for freestream Mach=1.4, figure to the right: freestream Mach=0.85 and 2 degrees incidence for both main wing and tail

Inlet of a combustion chamber (Jean-Philippe Légier):
The unsteady flow through the inlet of a simplified gas-turbine combustion chamber is studied. The inlet is composed of three inlets for air (in the middle) and fuel (outer sections). The flow is laminar at Re=16.000. In this initial work only the correct boundary conditions and the influence of the mesh are investigated, no chemistry is taken into account. The entire project is continued in the frame of a 5 month trainee (DEA) with the aim to study ignition and flame stabilization in the chamber using a chemistry model.

Pressure distribution.

Iso-vorticity shading.