An experimental investigation of the redistribution of gas stream total temperature in a high turning angle transonic planar cascad

Early testing at the National Research Council of Canada's (NRC) Highly Loaded Turbine Test Rig revealed what appeared to be the redistribution of the gas stream total temperature field as it passed through a transonic turbine nozzle and furthermore that there was an apparent change in area averaged total temperature across the nozzle row. In order to examine these observations a transonic planar cascade of the exhauster type was constructed at NRC. Tests were carried out at pressure ratios giving nozzle isentropic exit Mach numbers ranging from low subsonic to low supersonic (0.31 $leq$ M$sb{a}leq$ 1.36). Wedge probes were used to measure total pressure, total temperature and flow angles downstream of the nozzle blades.;Results of this detailed experimental investigation decisively indicated that the gas stream total temperature at the nozzle exit was highly redistributed. This total temperature separation or energy redistribution was strongly dependent on Mach number, with a maximum temperature separation of 36.0 $spcirc$F (20.0 $spcirc$C) occurring just prior to M$sb{a}$ = 1.0.