COMPUTATIONAL INVESTIGATION OF FLOW WITHIN C-D RECTANGULAR SUPERSONIC NOZZLE AND IMPULSE TURBINE

In this thesis, CFD analysis of flow within, Convergent - Divergent rectangular supersonic nozzle and supersonic impulse turbine with partial admission have been performed. The analysis has been performed according to shape of a supersonic nozzle and length of axial clearance, objective is to investigate the effect of nozzle-rotor interaction on turbine's performance. It is found that nozzle-rotor interaction losses are largely dependent on axial clearance which affects the flow with in nozzle and the extent of flow expansion. Therefore nozzle-rotor interaction losses can be decreased by selecting appropriate length of axial clearance. The work is carried in two stages: 1. Modeling and analysis of flow for rectangular convergent divergent supersonic nozzle. 2. Prediction of optimal axial gap between the Nozzle and rotor blades by allowing the above nozzle flow. In the present work, flow through the convergent divergent nozzle study is carried out by using a finite volume commercial code, FLUENT 6.2. The nozzle geometry is modeled and grid is generated using GAMBIT 2.3 Software. Computational results are in good agreement with the experimental ones.