Answer Happy

It is required to construct a hydraulic turbine (inward Francis type) for a hydraulic power plant to operate under the following conditions: rotating speed N = 110 rpm, discharge Q = 11 m3/s, the radial velocity at the inlet Cr1 = 2 m/s, the radial velocity at exit Cr2 = 9.5 m/s and the physical data are: the outside diameter D1 = 4.5 m, the absolute inlet angle a1 = 15°, the absolute exit angle a2 = 90° (radial flow at exit). Assume that the potential energy is constant (Z1 = Z2), the pressure head at exit equal 6 m, the hydraulic losses are 2 m, and no draft tube. Calculate the following: A) The Head subjected on the turbine in meters. B) The specific speed. 39.4 19.7 78.8 142.0 2.9 2.9 19.7 78.8 142.0 39.4 C) The pressure head at entrance in kg/cm2. D) It is required to construct a prototype to predict the actual machine performance, the assumed outside diameter D2 of the prototype was 0.3 m and the hydraulic circuit in the laboratory has the following specification: Available head = 5.5 m, Hydraulic efficiency = 0.8. Find the required speed, in RPM: 39.4 19.7 780 142.0 139 78.8 39.5 O 2.9 75.8 390 E) Based from the data of question item "D" find the water horsepower. 9.04 1.13 19.8 4.52 2.90