Numerical simulation of limit-cycle oscillations of a cropped delta wing using the full Navier-Stokes equations

This paper presents simulations of limit-cycle oscillations of a cropped de lta wing using a computational technique that implicitly couples a full Nav ier-Stokes solver to a linear structural solver. Computational results are compared with existing experimental measurements of the limit-cycle respons e of the delta wing. The limit-cycle oscillation is shown to consist primar ily of a response of the first bending mode and the first torsional mode. A erodynamic features of the limit cycle identified include a leading-edge vo rtex and a double shock structure. The leading edge vortex acts like an aer odynamic spring and provides the physical mechanism for the evolution of th e limit cycle on the delta wing. Computations are repeated using the Euler equations to determine if the inviscid flow equations adequately simulate t he observed limit cycle response.