An A/C plant is designed for a room with the following conditions: outdoor conditions 40 F db / 60% r.h., required indoor conditions 70 F db / 50% r.h., amount of air circulation 15 ft^3/min/person, room capacity 50 people. The required condition is achieved first by heating and then by adiabatic mixing. Show the pro cess on an e-version of a psych-chart, and thus determine the following: a. Heating capacity of the coil (BTU/min) b. Capacity of the humidifier (lbm/min)

An A/C plant is designed for a room with the following conditions: outdoor conditions 40 F db / 60% r.h., required indoor conditions 70 F db / 50% r.h., amount of air circulation 15 ft^3/min/person, room capacity 50 people. The required condition is achieved first by heating and then by adiabatic mixing. Show the pro cess on an e-version of a psych-chart, and thus determine the following: a. Heating capacity of the coil (BTU/min) b. Capacity of the humidifier (lbm/min)

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 8RQ: Frost accumulates on the evaporators of forced-draft refrigerators because A. they are generally...

See similar textbooks

Similar questions

In a certain semiconductor plant, the following condition exist on the intake side of thecompressor:Intake temperature - 28oCRelative humidity - 70%Volume of air drawn - 1,000 m3/hAfter compressing air to 7 bar, temperature rises to 40oC. Determine the following:a) Quantity of water before compressionb) Quantity of water after compressionc) Quantity of water occurring in the production aread) Total amount of water precipitated in the system
A horizontal move to the right on the psychrometric chart corresponds to which of the following? Select all that apply. A) A decrease in specific B) An increase in enthalpy. C) A decrease in D) A decrease in humidity ratio. E) A decrease in relative F) Which of the following equations is correct to calculate heat flow by water? A) Q = 500 * GPM * AT B) Q = 4.5 * CFM * AH C) Q = 1.1 * CFM * AT D) 8) Identify which of these equations should be used for the following load estimates:…
An engineer has been given the following data on a conditioned room: Sensible heat gain 30 kW Latent heat gain 15 kW Supply air 18°C Outdoor air 35°C DB and 24°C WB Desired room condition 27°C DB and 50% RH For ventilation, 15% is outdoor air, the balance of air requirement being recirculated from room conditioned with some portion being by-passed around the cooling coil. There is no reheater, the desired room state is attained by the by-passing of air. It is found that the apparatus DP temperature of coil is 10°C. Find the: a. tons of refrigeration; and b. mass flow rate of the time by-passed air.
39 - A fixed volume insulated tank, which was initially empty, was connected by a valve to a distribution line carrying helium gas at a temperature of 125ºC. The valve is opened first and closed when the pressure is the same as the distribution line pressure. What is the final internal energy of helium in the tank? (Internal energy of the warehouse in the final state = Enthalpy of the distribution line). (Cp=5.1926) will be taken. a) 2066.7 kJ/kg B) 2014.7 kJ/kg NS) 701.0 kJ/kg D) 649.1 kJ/kg TO) 2118.6 kJ/kg
15 - A fixed volume insulated tank, initially empty, was connected to a distribution line carrying helium gas at a temperature of 135ºC by means of a valve. The valve is opened first and closed when the pressure is the same as the distribution line pressure. What is the final internal energy of helium in the tank? (Internal energy of the warehouse in the final state = Enthalpy of the distribution line). (Cp=5.1926) will be taken. a) 701.0 kJ/kg B) 597.1 kJ/kg NS) 2014.7 kJ/kg D) 2066.7 kJ/kg TO) 2118.6 kJ/kg
RESENDING QT - NEED ANSWERS TO REMAINING 3 QTS 1.4, 1.5, 1.6 1.1 Determine the electrical power supplied to a boiler when the temperature of the entering water is 20 C and the exiting temperature is 89 C. The flow of.the pressured water is 2 Kg/s. There is a negligible pressure drop through this boiler and it operates at a constant pressure of 3 bars. The specific heat is c = 4,370 J/(Kg K). There is a 1.5(105 ) W rate of heat loss from the boiler during this process to a surrounding at 293.2 k. Consider steady state conditions. 1.2 Calculate the total rate of entropy production in Problem 1.1. 1.3 Calculate the total rate of exergy destruction (W) in Problem 1.1. The dead state temperature is 293.2 K and pressure is 1 bar. 1.4 Calculate the mass flowrate of fuel (natural gas, CH4) required to heat the water flow to the conditions of problem 1.1 if the electrical heating device is replaced with a gas fired boiler. The high heating value (HHV) of the fuel is 50.02 MJ/kg 1.5 Calculate…
Q1.A refrigeration facility is cooling down 2.5 kg dry air per second from T = 35 degrees Celsius, %RH = 75% to 18 degrees Celsius. How much water will the facility condense per hour? *note: please provide complete solution. you may use psychometric chart if needed. please explain in detail, thank you.
HVAC UPVOTE WILL BE GIVEN. ANSWERS ARE GIVEN ALREADY. PLEASE WRITE THE COMPLETE SOLUTIONS. A room contains moist air with a dry bulb temperature of 25°C and a wet bulb tempe rature of 21°C. Find d) DPT (Ans. DPT = 19.1°C) e) Specific Enthalpy (Ans. h = 60.5kj/kg)
0.25gm/sec of wet steam with 0.6MPa and dryness faction of 0.96 undergoes an isochoric process until it becomes saturated. Determine its dS, dH, Q, Wsf, and dU.
The sensible and latent heat gains to a room are 10 kW and 1 kW, respectively. The occupancy of the room is 12 people and the minimum fresh air allowance is 12 Li/s for each person. The outside summer design state is: 28ᵒC dry-bulb, 19.5 ᵒC wet bulb, 10.65 g/kg dry air. The room state is: 22 ᵒC dry-bulb, 50 percent saturation, 8.366 g/kg dry air, 43.39 kJ/kg dry air. Select a suitable air state, specify the states on and off the cooler coil and calculate the design cooling load. Analyse and check the cooling load. The temperature rise through the extract system is estimated as 0.5 ᵒC. A low velocity supply system is to be adopted and the temperature rise for supply fan power and duct heat gain is estimated 2ᵒ. Minimum fresh air requirement Plot the process on the psychrometric chart Determine the SHR. Contact Factor & Bypass Factor Total Cooling load.
The sensible and latent heat gains to a room are 10 kW and 1 kW, respectively. The occupancy of the room is 12 people and the minimum fresh air allowance is 12 Li/s for each person. The outside summer design state is: 28ᵒC dry-bulb, 19.5 ᵒC wet bulb, 10.65 g/kg dry air. The room state is: 22 ᵒC dry-bulb, 50 percent saturation, 8.366 g/kg dry air, 43.39 kJ/kg dry air. Select a suitable air state, specify the states on and off the cooler coil and calculate the design cooling load. Analyse and check the cooling load. The temperature rise through the extract system is estimated as 0.5 ᵒC. A low velocity supply system is to be adopted and the temperature rise for supply fan power and duct heat gain is estimated 2ᵒ. Solve for the following: 1. Minimum fresh air requirement2. Plot the process on the psychrometric chart3. Determine the SHR.4. Contact Factor & Bypass Factor5. Total Cooling load.
if you have design temperature instead of dry bulb temperature how do you obtain other values on the psychometric chart?