14-121 A laboratory has a volume of 700 m' and must have one complete air change per minute when being used. Outside atmospheric air at 100 kPa, 30°C dry bulb, and 60 percent rela- tive humidity is ducted into the laboratory air-conditioning equipment and conditioned to 20°C dry bulb and 12°C wet bulb, the required state for air supplied to the laboratory. (a) Sketch the system hardware and the psychrometric diagram for the process. (b) What outside atmospheric air mass flow rate is required for the air change, in kg/h? (c) Determine the mass flow rate of water condensed from the atmospheric air, in kg/min. (d) The cooling fluid in the air-conditioning system is chilled water, which has a 15°C temperature rise during the heat exchange process. Determine the chilled water mass flow rate, in kg/min.

14-121 A laboratory has a volume of 700 m' and must have one complete air change per minute when being used. Outside atmospheric air at 100 kPa, 30°C dry bulb, and 60 percent rela- tive humidity is ducted into the laboratory air-conditioning equipment and conditioned to 20°C dry bulb and 12°C wet bulb, the required state for air supplied to the laboratory. (a) Sketch the system hardware and the psychrometric diagram for the process. (b) What outside atmospheric air mass flow rate is required for the air change, in kg/h? (c) Determine the mass flow rate of water condensed from the atmospheric air, in kg/min. (d) The cooling fluid in the air-conditioning system is chilled water, which has a 15°C temperature rise during the heat exchange process. Determine the chilled water mass flow rate, in kg/min.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

An air-conditioning system is to take in air at 1 atm, 34 °C, and 70 % relative humidityand deliver it at 22 °C and 50 % relative humidity. The air flows first over the coolingcoils, where it is cooled and dehumidified, and then over the resistance heating wires,where it is heated to the desired temperature. Assuming that the condensate is removedfrom the cooling section at 10°C, determine a) the rate of heat supply in the heating section, and b) the mass flow rate of the steam required in the humidifying section
What is the temperature entering the cooling sectionwhen 25 kW of heat are removed and the air exits at 15 deg C, a relative humidity of 30% and a volumetric flowrate of 0.7 m^3/s?
A winter air-conditioning system adds for humidification 0.0025 kg/s of saturated steam at 100 kPa pressure to an airflow of 0.36 kg/s. The air is initially at a temperature of 15°C with a relative humidity of 20 percent. The barometric pressure is 90 kPaa. What is the dry temperature of the air leaving the humidifier °C?
A dryer is to deliver 1,000 kg/h of palay with final moisture content of 10%. The initial moisture content in the feed is 15% at atmospheric condition with 30 oC dry bulb and 20 oC wet bulb. The dryer is maintained at 45oC while the relative humidity of the hot humid air from the dryer is 80%. If the steam pressure supplied to the heater is 2 MPa, determine the following: a.) Palay supplied to the dryer in kg/h. b.) Temperature of the hot humid air from the dryer in oC. c.) Air supplied to dryer in cu m/h. d.) Heat supplied by the heater in k W. e.) Steam supplied to heater in kg/h.
Which is better for humidifying air, adding steam or water? Justify?
Air at a dry ball temperature of 75 ° C and RH 8% is passed over the cooling coil so that the air dry ball temperature becomes 30 ° C. How much heat is released from the air in the process? .... (kJ / kg)
An air-conditioning system operates at a total pressure of 1 atm and consists of a heating section and anevaporative cooler. Air enters the heating section at 14°C and 60 percent relative humidity at a rate of 30m3/min, and it leaves the evaporative cooler at 25°C and 45 percent relatively humidity. Determine (a) thetemperature and relative humidity of the air when it leaves the heating section, (b) the rate of heat transfer in theheating section, and (c) the rate of water added to air in the evaporative cooler.
A cooling tower receives 6 kg/s of water of 60oC. Air enters the tower at 32oC DB and 27oC WB temperatures and leaves at 50oC and 90 per cent relative humidity. The cooling efficiency is 60.6 per cent. Determine: (a) the mass flow rate of air entering, and (b) the quantity of make-up water required.
It is desired to reduce the temperature of the ambient air entering an air handling unit at a volumetric flow rate of 550 m3/min, at a temperature of 35°C and a relative humidity of 0.75 to 20°C and its relative humidity to 0.45. For this purpose, the air is first cooled to a temperature below the dew point by passing through a cooling coil, and after some moisture is taken by condensation, its temperature is increased to 20˚C by passing over a heating coil. In this way, the temperature of the ambient air at the outlet of the air handling unit is brought to 20˚C and its relative humidity to 0.45. It is assumed that the pressure remains constant at P=100 kPa. Relationships will be used in the calculations. a) Calculate the amount of moisture condensed per unit time.b) Find the amount of heat drawn from the air by the cooling coil.c) Calculate the amount of heat given to the air by the heating coil.d) Show the phase changes on the psychrometric diagram.
air at dry ball temperature is 35 ° C and RH 30%, air is heated to dry ball temperature 85 ° C. The heated air is then flowed through a humidifier to reduce RH to 25%. Determine the change in absolute humidity of air in initial to final conditions and change in air enthalpy in initial to final conditions
Compute the enthalpy of air at 60 percent relative humidity and 34 deg.C (Psat = 5.318 kPa), when the barometric pressure is 110 kPa.
Air at a dry ball temperature of 90 danC and 4% RH is passed over the cooling coil so that the air dry bulb temperature becomes 45˚C. how much heat is released from the air in the process? = (Kj / kg)