Numerical simulation of nozzle flow field with jet vane thrust vector control

Numerical simulations are performed to characterize the jet vane thrust vector control mounted in the rear of a rocket motor. The three-dimensional Navier-Stokes equations along with the K-epsilon turbulence model are solved in a hybrid mesh consisting of an unstructured grid and a structured grid. All essential flow features including the complex compression/expansion wave interactions emanating from the vane surfaces and shrouds are captured by simulation. The computed side force coefficients are seen to vary linearly with chamber pressure and vane deflection angles. A theoretical correlation has been developed by a non-linear regression analysis from the computational fluid dynamics (CFD) database to predict the force and moment coefficients for different chamber pressures, vane deflection angle, and roll offset angle. The theoretical correlation compare very well with full CFD simulation as well as the experimental data.