A centrifugal pump transports water with a volume flow rate of Q=0.07 m/s between two large...

   

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A centrifugal pump transports water with a volume flow rate of Q=0.07 m/s between two large reservoirs via a circular pipeline which has an internal diameter of 300 mm, as shown above. The two reservoirs are separated by height Z2-Z =5 m. At this volume flow rate, the total head loss through the pipe flow system is 20 m and the total hydraulic head loss through the pump is 5 m. As the impeller rotates, there is a leakage loss of QL = 180 litres/min within the pump. The circumferential area of the impeller inlet and outlet is reduced by 12% due to the effect of vane thickness, and the radial velocity through the impeller is constant at C, 3.7 m/s. The width of the inlet to the impeller is b = 60 mm and the width of the outlet to the impeller is b = 24 mm. The vane outlet angle is B = 60 to the radial direction. The mechanical efficiency is nm = 90%, and the slip factor is = 0.71. Assume no swirl at the inlet to the impeller. e) Calculate the angular velocity, 2, of the impeller. Provide your answer in revolutions per minute (rpm), rounding your answer to the nearest rpm. Show steps (Your score will not be affected.) Answer: Round your answer to the nearest integer. Submit part f) Calculate the overall efficiency of the pump, no. Provide your answer as a percentage, round to the nearest percent. Show steps (Your score will not be affected.) Answer: g) The centrifugal pump is located at a height of Z, = 2.5 m, and a quarter of the total head losses occur before the inlet to the pump. Noting that the temperature of the water is T = 10C, calculate the suction specific speed, Nss. Round your answer to 1 decimal place. Suction valve Zs Discharge valve d Pump Zd Datum A centrifugal pump transports water with a volume flow rate of Q=0.07 m/s between two large reservoirs via a circular pipeline which has an internal diameter of 300 mm, as shown above. The two reservoirs are separated by height Z2-Z =5 m. At this volume flow rate, the total head loss through the pipe flow system is 20 m and the total hydraulic head loss through the pump is 5 m. As the impeller rotates, there is a leakage loss of QL = 180 litres/min within the pump. The circumferential area of the impeller inlet and outlet is reduced by 12% due to the effect of vane thickness, and the radial velocity through the impeller is constant at C, 3.7 m/s. The width of the inlet to the impeller is b = 60 mm and the width of the outlet to the impeller is b = 24 mm. The vane outlet angle is B = 60 to the radial direction. The mechanical efficiency is nm = 90%, and the slip factor is = 0.71. Assume no swirl at the inlet to the impeller. e) Calculate the angular velocity, 2, of the impeller. Provide your answer in revolutions per minute (rpm), rounding your answer to the nearest rpm. Show steps (Your score will not be affected.) Answer: Round your answer to the nearest integer. Submit part f) Calculate the overall efficiency of the pump, no. Provide your answer as a percentage, round to the nearest percent. Show steps (Your score will not be affected.) Answer: g) The centrifugal pump is located at a height of Z, = 2.5 m, and a quarter of the total head losses occur before the inlet to the pump. Noting that the temperature of the water is T = 10C, calculate the suction specific speed, Nss. Round your answer to 1 decimal place. Suction valve Zs Discharge valve d Pump Zd Datum