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 34m/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.