Chapter 6, Problem 6.11CU

Liquid water enters a valve at 300 kPa and exits at 275 kPa. As water flows through the valve, the changein its temperature, stray heat transfer with the surroundings, and potential energy effects are negligible.Operation is at steady state. Modeling the water as incompressible with constant density, ? = 1000 ?g/?^3,determine the change in kinetic energy per unit mass of water flowing through the valve, in kJ/kg.

1. As shown in the figure below, Refrigerant 134a enters a condenser operating at steady state at 70 lbf/in2, 160 °F and is condensed to saturated liquid at 60 lbf/in on the outside of tubes through which cooling water flows. In passing through the tubes, the cooling water increases in temperature by 20 'F and experiences no significant pressure drop. Cooling water can be modeled as incompressible with v-0.0161 ft'/lb and c = 1 Btu/lb R. The mass flow rate of the refrigerant is 3100 lb/h. Neglecting kinetic and potential energy effects and ignoring heat transfer from the outside of the condenser, determine: (a) The volumetric flow rate of the entering cooling water, in gal/min (b) The rate of heat transfer, in Btu/h, to the cooling water from the condensing refrigerant (5 points) Refrigerant 134a P= 70 in. T= 160 F 3100 heh 7,-7,-20F-20R Reirigerant 134a [P-60 lbin V Saturated liquid

Refrigerant 134a enters an insulated diffuser as a saturated vapor at 80°F with a velocity of 1400 ft/s. The inlet area is 1.4 in². At the exit, the pressure is 400 lb/in² and the velocity is negligible. The diffuser operates at steady state and potential energy effects can be neglected. Determine the mass flow rate, in lb/s, and the exit temperature, in °F. Step 1 Your answer is correct. Determine the mass flow rate, in lb/s. m = 28.887 Hint Step 2 * Your answer is incorrect. Ib/s. Determine the exit temperature, in °F. T2=₁276.3 °F Attempts: 1 of 4 used

Refrigerant 134a enters an insulated diffuser as a saturated vapor at 80°F with a velocity of 1400 ft/s. The inlet area is 1.4 in². At the exit, the pressure is 400 lb/in² and the velocity is negligible. The diffuser operates at steady state and potential energy effects can be eglected. Determine the mass flow rate, in lb/s, and the exit temperature, in °F. Step 1 Your answer is correct. Determine the mass flow rate, in lb/s. m = 28.887 Hint Step 2 lb/s. Determine the exit temperature, in °F. T₂ = i OF Attempts: 1 of 4 used

3.972 kilograms per second of steam is allowed to pass through a nozzle operating at steady state with initial conditions of 46 bar, 400° C and is 15 m/s. The steam flows with negligible heat transfer and no significant change in potential energy. Determine the exit area in cm? if final pressure and velocity are 16 bar and 650 m/s, respectively.

Refrigerant 134a enters an insulated diffuser as a saturated vapor at 80 deg F with a velocity of 800 ft/s. The inlet area is 1.4 in^2. At the exit, the pressure is 400 lbf/in2 and the velocity is negligible. The diffuser operates at steady state and potential energy effects can be neglected. Determine the mass flow rate, in lb/s, and the exit temperature, in deg F.

Air flows through a nozzle. It enters at 20 bar and 1100°F and exits at 10 bar and 800°F. The inlet diameter ratio between outlet diameter is 3. Consider steady state, determine air inlet and outlet velocities, in ft/s

T-4

Refrigerant 134a enters an insulated diffuser as a saturated vapor at 80°F with a velocity of 1400 ft/s. The inlet area is 1.4 in². At the exit, the pressure is 400 lbf/in² and the velocity is negligible. The diffuser operates at steady state and potential energy effects can be neglected. Determine the mass flow rate, in lb/s, and the exit temperature, in °F. Step 1 Determine the mass flow rate, in lb/s. m = i lb/s.