For the steam power plant shown in Problem 4.118, determine the rate of heat transfer in the economizer, which is a low-temperature heat exchanger. Also find the rate of heat transfer needed in the steam generator.

Data from Problem 4.118,

The following data are for a simple steam power plant as shown in Fig. P4.118. State 6 has x6 =0.92 and velocity of 200 m/s. The rate of steam flow is 25 kg/s, with 300 kW of power input to the pump. Piping diameters are 200mmfrom the steam generator to the turbine and 75 mm from the condenser to the economizer and steam generator. Determine the velocity at state 5 and the power output of the turbine.

Transcribed Image Text:

State 1 2 3 4 6 7 P, kPa 6200 6100 5900 5700 5500 10 9 T, °C 45 175 500 490 40 h, kJ/kg 194 744 3426 3404 168 Steam Turbine generator Cooling Condenser water Economizer -Wp Pump FIGURE P4.118