A Francis turbine has the following specifications. Impeller vanes are backward curved at inlet with anti-clockwise...

 

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A Francis turbine has the following specifications. Impeller vanes are backward curved at inlet with anti-clockwise rotation of the runner. Vane Inlet angle = 40 relative to U1 Absolute velocity at outlet is radial. Mass flow rate = 1962 kg.s-1 Runner speed = 600 rpm Inlet diameter = 762 mm Outlet diameter = 382mm Density @ 15 C = 999 kg.m-3 Inlet blade width = 101 mm Mechanical Efficiency = 95 % Fluid properties The blades occupy 10% of the respective areas at both inlet and outlet. Calculate: 2.1) The guide vane outlet angle (a1) relative to U1 with the aid of a velocity diagram. (9) 2.2) The relative velocity at outlet (Cr2 and the runner vane width at outlet (B2) if the velocity of flow remains constant across the runner (f1 =f2) 2.3) The Euler head absorbed by the runner. 2.4) The shaft power of the turbine. (6) (2) (1) Total [18] A Francis turbine has the following specifications. Impeller vanes are backward curved at inlet with anti-clockwise rotation of the runner. Vane Inlet angle = 40 relative to U1 Absolute velocity at outlet is radial. Mass flow rate = 1962 kg.s-1 Runner speed = 600 rpm Inlet diameter = 762 mm Outlet diameter = 382mm Density @ 15 C = 999 kg.m-3 Inlet blade width = 101 mm Mechanical Efficiency = 95 % Fluid properties The blades occupy 10% of the respective areas at both inlet and outlet. Calculate: 2.1) The guide vane outlet angle (a1) relative to U1 with the aid of a velocity diagram. (9) 2.2) The relative velocity at outlet (Cr2 and the runner vane width at outlet (B2) if the velocity of flow remains constant across the runner (f1 =f2) 2.3) The Euler head absorbed by the runner. 2.4) The shaft power of the turbine. (6) (2) (1) Total [18]