Consider a combination-boiler feed pump and booster pump similar to the arrangement shown in Example 8.8. The flow rate is 2,484,000 lbm/hr, and the specific enthalpy increase from inlet to outlet is 16.79 Btu/lbm. Saturated liquid water enters at a pressure of 1.55 in -Hg absolute. Estimate 

(a) The power to drive the pump in MW 

(b) The outlet pressure in MPa.

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Steam in Steam turbine Example 8.8 Feedwater Pump H₂O (1) 20 MPa H₂0 (1) Four-stage centrifugal pump 8 kPa Single-stage booster pump Reduction gear box The main boiler feed pump for a 250-MW elec- trical generating unit consists of a four-stage centrifugal pump in series with a single-stage booster pump. A steam turbine with a 6-MW shaft output drives the pump system, as shown in the sketch. Saturated liquid water enters the pump at 8.0 kPa with a flow rate of 250 kg/s and exits at 20 MPa. Determine the isentropic effi- ciency of the pump.