Chapter 5, Problem 5.20P

As shown in the figure below, moist air at T₁ = 36°C, 1 bar, and 35% relative humidity enters a heat exchanger operating at steady state with a volumetric flow rate of 10 m³/min and is cooled at constant pressure to 22°C. Ignoring kinetic and potential energy effects, determine: (a) the dew point temperature at the inlet, in °C. (b) the mass flow rate of moist air at the exit, in kg/min. (c) the relative humidity at the exit. (d) the rate of heat transfer from the moist air stream, in kW. (AV)1, T1 P₁ = 1 bar 11 = 35% 120 T₂=22°C P2 = 1 bar

Air at T₁-24°C, p₁-1 bar, 50% relative humidity enters an insulated chamber operating at steady state with a mass flow rate of 3 kg/min and mixes with a saturated moist air stream entering at T₂-7°C, p2-1 bar. A single mixed stream exits at T3-17°C, p3-1 bar. Neglect kinetic and potential energy effects Step 1 Your answer is correct. Determine mass flow rate of the moist air entering at state 2, in kg/min. m2 = 2.1 Hint kg/min Using multiple attempts will impact your score. 5% score reduction after attempt 2 Step 2 Determine the relative humidity of the exiting stream. Փ3 = i % Attempts: 1 of 3 used

A reservoir at 300 ft elevation has a 6-in.-diameter discharge pipe located 50 ft below the surface.  The pipe is 600 ft long and drops in elevation to 150 ft where the flow discharges to the atmosphere. The pipe is made of riveted steel with a roughness height of 0.005 ft.   Determine the flow rate without a head loss Determine the flow rate with the pipe friction head loss. (hints:  Since the velocity is not known for part b and the Reynolds number and friction factor depend on velocity, you will need to iterate to find the solution.  A good first guess is the velocity from part (a))