Water is heated in an insulated, constant diameter tube by a 5-kW electric resistance heater. If the water enters the heater steadily at 15°Cand leaves at60°C, determine the mass flow rate of water.

ce an answer is submit you will be unable to return to this part. A refrigeration system is to cool bread loaves with an average mass of 390 g from 30°C to -10°C at a rate of 1200 loaves per hour with refrigerated air at -30°C. Take the average specific and latent heats of bread to be 2.93 kJ/kg-°C and 109.3 kJ/kg. Determine the size of the compressor of the refrigeration system, in kW, for a COP of 1.2 for the refrigeration system. 4 The size of the compressor of the refrigeration system is kW.

The remaining wet steam exits the turbine at 11.5 kPa with a quality of 0.88. Determine the minimum pipe diameters required to restrict the maximum inlet velocity to 50 m/s, the maximum extraction velocities each to 75 m/s, and the turbine outlet velocity to 130 m/s. Consider a steam turbine in which steam enters at 10.45 MPa and 780 K with a flow rate of 38.739 kg/s. As shown in the sketch, a portion of the steam is extracted from the turbine after partial expansion at three different locations. The extracted steam is then led to various heat exchangers. The mass flow rates and the temperatures and pressures at each extraction point are given in the following table: Inlet Steam turbine Extraction Location rin(kg/s) P (MPa) T(K) 1 23 4.343 3.054 620 4.345 0.332 482 Extraction 3. 2.871 0.136 x= 0.949 locations Exit 123

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