Numerical investigation of profile losses in the nozzle vane cascades at different relative pitches

Investigation of the flow and aerodynamic losses in the turbine blade cascade with profile N4U1 is carried out. There was shown that change of relative pitch in the blade cascade sufficiently influences on distribution of Mach number in the blade channel and on local velocities along blade profile. The relative pitch also influences on flow parameter distribution after blade cascade and on profile loss coefficient. For studied turbine cascades the optimal value of the relative pitch is determined. At this pitch the minimum profile losses exist in the blade cascade.