Computational Fluid Dynamics
Numerical modeling is becoming increasingly important for developing advanced vehicles.
We initiated Computational Fluid Dynamics (CFD) studies aimed at optimizing configurations
of PARV and WIG.
It is known that excessive mechanization of a ground-effect wing in high-speed motion may
result in the lift decrease due to pressure growth on the suction side of the wing and flow
separation. However, special airfoil sections and moderate mechanization can be beneficial.
Below an example of our simulations using computer program Fluent is shown for a flap-augmented
NACA 4412 wing section in the ground proximity. Reynolds number is 10e6. Calculated lift and
drag coefficients: bare wing, CL = 0.733 and CD = 0.010; wing with flap, CL = 1.410 and CD = 0.018.
A strong augmentation of the lift and a moderate increase of the lift-to-drag ratio are provided
by the deflected flap on this wing in the ground effect.
Oblique jet impingement on ground in cross flow is important for PAR systems. An example of pressure and velocity
contours is shown here for the case of cross-flow velocity being 1/5 of the jet nozzle velocity. The jet is
generated by a momentum source located inside the duct. The ground wall is moving with the cross-flow velocity.
