Problem 9 A 40-kg iron block initially at 400°C is quenched in an insulated tank that contains 150 kg of water at 20°C. Assuming the water that vaporizes during the process condenses back in the tank, determine the total change during this process. Problem 10 An adiabatic pump is to be used to compress saturated liquid water at 15 kPa to a pressure to 20 MPa in a reversible manner. Determine the work input using (a) entropy data from the compressed liquid table, (b) inlet specific volume and pressure values, (c) average specific volume and pressure values. Also, determine the errors involved in parts (b) and (c).

A Carnot vapor refrigeration cycle operates between thermal reservoirs at 7°C and 28°C. The working fluid is saturated vapor at the end of the compression process and saturated liquid at the beginning of the expansion process. Determine the operating pressures in the condenser and evaporator, in bar, and the coefficient of performance for each of the following as the working fluid. (a) Refrigerant 134a (b) Refrigerant R22 (c) water (d) ammonia

Friction loss in pumping oil to pressurized tank an oil having a density of 833 kg/m3 and a viscosity of 3.3 x 10³ Ns/m² is pumped form an open tank to a pressurized tank held at 345 kPa (gage). The oil is pumped from an inlet at the side of the open tank through a line of commercial steel pipe 3-inch nominal pipe size r of internal diameter 77.92 mm at the rate of 3.494 x 10³ m³/s. The length of straight pipe is 122m and the pipe contains two elbows (90") and a globe valve half open. The level of the liquid in the open tank is 20 m above the liquid level in the pressurized tank. The pump efficiency is 65%. Calculate the kW power of the pump (1.40 HP) elbow Globe valve 20 m PUMP

compressing it isothermally. Determine the required change in pressure. 2-45 Saturated refrigerant-134a liquid at 10°C is cooled to 0°C at constant pressure. Using coefficient of volume expan- sion data, determine the change in the density of the refrigerant.