TY - CPAPER AB - An experimental investigation into pre-swirl effectivenessand receiver hole discharge coefficient characteristics for ahigh radius injection pre-swirl cooling systems was carried outon a physically representative experimental rig with a 450 mmdiameter rotor. The receiver holes and pre-swirl nozzle werelocated at a radius of 181 mm and 180 mm respectively. Theexperimental work was mainly conducted at 5000-12000 rpm,4 bar absolute pressure and 1.132 kg/s air supply. Themaximum air supply temperature was 190ºC.Pressure and temperature distributions in the pre-swirlsystem were examined with an emphasis on the velocityeffectiveness of the pre-swirl system as a whole and on thedischarge coefficients of the rotating 'receiver holes' in therotor. The results showed that the velocity effectivenessincreased with increasing swirl ratio resulting in reduced bladecooling flow temperature. Different seal flow configurationscaused very different effectiveness at different speeds, butoutflow through the inner and outer seals always gave thehighest effectiveness compared other configurations.Increasing the seal flow rate reduced the effectiveness. For thecoefficient of discharge, except for the low speed range, itincreased with increase in swirl ratio for most speeds. AU - Peng,Z AU - New,P AU - Long,CA AU - Childs,PRN EP - 241 PY - 2006/// SP - 235 TI - Operating characteristics of a high radius pre-swirl cooling system ER -