5.90 A water turbine wheel rotates at the rate of 50 rpm in the di- rection shown in Fig. P5.90. The inner radius, r2, of the blade row is 0.6 m, and the outer radius, r, is 1.2 m. The absolute velocity vector at the turbine rotor entrance makes an angle of 20 with the tangential direction. The inlet blade angle is 60 relative to the tan- gential direction. The blade outlet angle is 120. The flowrate is 0.6 m/s. For the flow tangent to the rotor blade surface at inlet and outlet, determine an appropriate constant blade height, b, and the corresponding power available at the rotor shaft. b -20 W 60 50 rpm 120 W Section (1) Figure P5.90 r2 = 0.6 m V 1.2 m Section (2) Q = 0.6 m/s