A three-dimensional finite element algorithm for prediction of V/STOL jet-induced flowfields

A three dimensional mathematical model of the basic V/STOL jet, and the flow in the associated near field using a formal order of magnitude analysis was constructed. This produces a parabolized approximation to the steady, time averaged, three dimensional Navier-Stokes equations for a turbulent subsonic flow. A continuity constraint finite element numerical solution algorithm is identified, which independently enforces ordered phenomena for solution of the equation system including transport equations for turbulence kinetic energy and dissipation parameters. The numerical solution of the established equation system yields prediction of core vortex roll up, far field deflection of the cross flow, near field entrainment of the cross flow into the jet, and wake flow reversal with additional entrainment into the jet core. The primary causal mechanism is computationally assessed to be the turbulence interaction on the upstream face of the jet, as verified by results from a range of computational experiments.