Numerical Simulation of Stage Jettisoning of a Two-Stage Rocket with Different Separation Distances

CFD simulations were carried out to evaluate the flow field during the jettisoning process of a two-stage rocket using an inhouse developed RANS code. Two simulations with stage separation distances of 500 mm and 1,000 mm were considered for simulation. For the 500 mm case, there was a severe ‘jet-upstream’ flow interaction which resulted in an upstream flow separation and hence can cause large drag rise. However, there was no such observation of flow separation anywhere on the upper stage for the 1,000 mm case. A study was carried out to evaluate the effect of spatial order of accuracy for modelling the governing Reynolds Averaged Navier–Stokes (RANS) equations on the simulation results. © 2012, The Institution of Engineers (India).