4. [5 Pts] Consider a mixing chamber at steady state with two inlets and one outlet...

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4. [5 Pts] Consider a mixing chamber at steady state with two inlets and one outlet as shown below. Inlet 1 transports saturated water at 150 C at 2 kg/s, and inlet 2 transports compressed liquid water at 100 C and 500 kPa at 1 kg/s. After mixing and heating in the chamber, we get superheated vapor at 250 C at 300 kPa. All inlets and outlets have the same cross-sectional area of 100 cm. Ignore potential energy but not the kinetic energy. 1 2 QH Condenser Expansion valve or capillary tube Evaporator Mixing chamber 5. [10 Pts] A 500 W refrigerator uses R-410A, which goes through the following cycle: System boundary 3 QL (a) What is the flow speed in the first inlet? [1 Pt] (b) What is the flow speed in the second inlet? [1 Pt] (c) What is the flow speed in the outlet? [1 Pts] (d) What is the heating rate in the chamber? [2 Pts] Work Just before evaporator Saturated liquid at -50 C Just before compressor Superheated at -20 C & 100 kPa Just before condenser Saturated gas at -30 C Ignore gravity and heat loss during transportation. (a) What is the mass flow rate? [2 Pts] (b) What is QH? [2 Pts] (c) What is QL? [2 Pts] (d) What is the flow speed before and after the expansion valve? [1 Pt] (e) What is the coefficient of performance of cooling and heating? [3 Pts] Just after condenser liquid at -50 & 100 kPa 4. [5 Pts] Consider a mixing chamber at steady state with two inlets and one outlet as shown below. Inlet 1 transports saturated water at 150 C at 2 kg/s, and inlet 2 transports compressed liquid water at 100 C and 500 kPa at 1 kg/s. After mixing and heating in the chamber, we get superheated vapor at 250 C at 300 kPa. All inlets and outlets have the same cross-sectional area of 100 cm. Ignore potential energy but not the kinetic energy. 1 2 QH Condenser Expansion valve or capillary tube Evaporator Mixing chamber 5. [10 Pts] A 500 W refrigerator uses R-410A, which goes through the following cycle: System boundary 3 QL (a) What is the flow speed in the first inlet? [1 Pt] (b) What is the flow speed in the second inlet? [1 Pt] (c) What is the flow speed in the outlet? [1 Pts] (d) What is the heating rate in the chamber? [2 Pts] Work Just before evaporator Saturated liquid at -50 C Just before compressor Superheated at -20 C & 100 kPa Just before condenser Saturated gas at -30 C Ignore gravity and heat loss during transportation. (a) What is the mass flow rate? [2 Pts] (b) What is QH? [2 Pts] (c) What is QL? [2 Pts] (d) What is the flow speed before and after the expansion valve? [1 Pt] (e) What is the coefficient of performance of cooling and heating? [3 Pts] Just after condenser liquid at -50 & 100 kPa