Numerical simulation on flow field of the clamshell thrust reverser with landing flap deployed

Computational fluid dynamics (CFD) technology was used to investigate the flow field distribution characteristic of a clamshell thrust reverser with landing flap deployed. The computational grid was generated with unstructured tetrahedron and hexahedron meshes, and Spalart-Allmaras (S-A) turbulent model based on solving Reynolds-averaged Navier-Stokes (RANS) equations was adopted. The results show that, in the range of landing speed, the hot reverse exhaust flow from the clamshell thrust reverser is not re-injected into the engine inlet, but it impinges on part of the aerofoil and pylon. As landing speed decreases, the hot reverse exhaust flow spreads forward and laterally deeper, so it may be re-injected by near engine inlet if the aerofoil sweepback is large enough, resulting possibly in inlet distortion. When landing speed decreases down to 34 m/s, the hot reverse exhaust flow starts to impinge on the ground, which may wind up some dross to the inlet. At last, the reverse thrust decreases as landing speed decreases.