Chapter 7, Problem 7.31P

A heat pump and a pipe through which water flows at a flow rate of 0.05kg/s are in interaction. At the inlet of the pipe, the water is in a saturated liquid state at 2 bar pressure. After the water in the pipe interacts with the heat engine, the water is in the form of a saturated gas at 2 bar pressure at the outlet of the pipe. The heat pump can only obtain energy from a reservoir at 16 ℃. Engineers have calculated that 25kW of power must be transferred to the heat engine for this process to take place. Explain whether the engineers were right.

Two pounds of carbon dioxide (CO₂) as an ideal gas executes a Camot power cycle while operating between thermal reservoirs at 480 and 100°F. The pressures at the initial and final states of the isothermal expansion are 400 and 200 lb/in², respectively. The specific heat ratio is k-1.24. Determine the thermal efficiency, the work for the isothermal expansion, in Btu, and the work for the adiabatic expansion, in Btu. Step 1 Determine the thermal efficiency. 7 = i Save for Later %

Two pounds of carbon dioxide (CO₂) as an ideal gas executes a Carnot power cycle while operating between thermal reservoirs at 470 and 100°F. The pressures at the initial and final states of the isothermal expansion are 400 and 200 lb/in², respectively. The specific heat ratio is k-1.24. Determine the thermal efficiency, the work for the isothermal expansion, in Btu, and the work for the adiabatic expansion, in Btu. Step 1 Your answer is correct. Determine the thermal efficiency. 7= 39.798 Hint Step 2 % * Your answer is incorrect. Determine the work during the isothermal expansion, in Btu. W23 29.971 Btu Attempts: 2 of 4 used