Nitrogen gas flows through a long, constantdiameter adiabatic pipe. It enters at 100 psia and 120°F and leaves at 50 psia and 70°F. Calculate the velocity of the nitrogen at the pipe’s inlet and outlet.

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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An isothermal compression process is used in air flowing at 10 kg mol/s at 28°C and 25 psia to 75 psia. Determine the power (in MW) required if the mechanical efficiency is 60% and Cp/Cv = 1.4.

An adiabatic capillary tube is used in some refrigeration systems to drop the pressure of the refrigerant from the condenser level to the evaporator level. The R-134a enters the capillary tube as a saturated liquid at 50°C and leaves at -22.00°C. Determine the quality of the refrigerant at the inlet of the evaporator. Use data from the tables. (Round the final answer to three decimal places.) The quality of the refrigerant is