006m 031m A turboshaft engine operates at an 881 pressure ra

(0.06m; 0.31m) A turboshaft engine operates at an 8.8:1 pressure ratio, with a mass flow of 77kg/s, assuming air as the working fluid. The exhaust static temperature is 473°C, and the turbine inlet total temperature is 1000°C. The mean blade radius is 0.4m, and the constant axial velocity is 200m/s. Estimate the blade height at the entrance and exit of the turbine. Assume mean radius is equal to the arithmetic mean radius, ie rm=(ro+ri)/2

Solution

From the above given data blade height can be calculated as follows

blade height at entrace = 4m

blade height at exit= 5 m