EFFECT OF SURFACE ROUGHNESS ON AERODYNAMIC PERFORMANCE OF TURBINE REAR STRUCTURE

Paper in proceedings, 2019

A turbine rear structure (TRS) is typically used to deswirl the flow from the low pressure turbine (LPT) and hence maximize the axial thrust. It is important to study the effect of surface roughness on aerodynamic performance of TRS. Numerical simulations with surface roughness are performed and results are compared with the data from experiments. Comparisons show that the trends between the numerical analysis and the experiments are in line with one another. Further understanding of numerical analysis shows that, at higher Reynolds number, the effect ofsurface roughness is more significant when compared to the effects at low-Reynolds number. An attempt has been made to study the transition behavior in the presence of surface roughness. Since boundary layer measurements are planned for the rig, this numerical study provides good inputs in order to plan instrumentation..