Air at 31 C and 21% relative humidity is cooled (reduce in temperature) and humidified (added moisture) by means of an air washer until the relative humidity becomes 81% . How much moisture was added per kg of dry air. What was the air washer efficiency and the dew point temperature of the leaving air

Air at 31 C and 21% relative humidity is cooled (reduce in temperature) and humidified (added moisture) by means of an air washer until the relative humidity becomes 81% . How much moisture was added per kg of dry air. What was the air washer efficiency and the dew point temperature of the leaving air

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

Chapter34: Indoor Air Quality

Section: Chapter Questions

Problem 17RQ: The recommended relative humidity for a home is between A. 500/0 and 70%. B. and 40%. C. and 50%. D....

See similar textbooks

Similar questions

what is the relationship and formula of relative humidity and temperature?
RH2 = 43% What is the specific humidity of the air stream #1, w1 (lbm H2O/lbm air)? What is the specific humidity of the air stream #2, w2 (lbm H2O/lbm air)? What is mass flow rate of dry air in stream #1 (lbm/s)? What is mass flow rate of dry air in stream #2 (lbm/s)? What is the relative humidity of the outlet (%)?
What is the maxmium specific humidity of air at -30C is ________________and the maximum specific humdity of air at -10 C is _______________; therefore, the difference in maximum specific humidity between -30C and -10C is _____________. The maximum specific humidity of air at 30 C is ________________ and the maximum specific humidity of air at 10 C is ____________; therefore, the difference in maximum specific humidity between 30C and 10C is ______________.
ASHRAE standard 62.2 states that the minimum acceptable rate of airflow into and out of a room is 15cfm (cubic feet per minute). If air is supplied at 68°F with a relative humidity of 45%, how many gallons of water (minimum) must be added to a portable room humidifier before you go to sleep if you would like to maintain the room at 65% humidity for 7 hours?
In the case of heating the air with a heating coil, the absolute humidity of the air can either increase, or decrease. does not change. increases. decreases.
Using a psychometric diagram, describe the heating and humidification process from the following data. Initially the air was at dry bulb temperature (DBT) 35 ° C and RH 35%. air preheated to DBT 85 ° C. The heated air is then flowed through a humidifier to increase the RH to 25%. for this process, count, a. change in absolute humidity of air from initial to final conditions = ..... (kg water / kg air) b. change in air enthalpy from initial to final conditions = ..... (kj / kg air)
What happens when relative humidity (RH) = 100%? a)if the air is continued to be cooled, at what temperature will the saturation point be reached? b)What happens if the air is continued to be cooled below the DBT you just found? (psychrometric chart image)
The total volume of a new house is 681 m3. Before the heat is turned on, the air temperature inside is 15°C, and the relative humidity is 42 percent. After the air is warmed to 20°C, how much water vapor must be added to the air to make the relative humidity 42 percent? _________kg
Q2) Air is supplied to an automobile cabin from the outside, where the temperature is 20F and the relative humidity is 70%. It is desired to keep the cabin at 70F and Ø = 60%. Hoe many pounds of water must be supplied to each pound of air entering the car cabin if these conditions are to be met? The barometric pressure is 29.5 in.Hg. %3D Ans. (0.00797 lbs/Ibdry air)
11 of 13 The temp. of the air in a dryer is maintained constant by the use of steam coils w/in the dryer. the product enters the dryer at the rate of one metric ton per hour. The initial moisture content is 3 kg moisture per kg of dry solid. Air entors the dryer w/ humidity ratio of 0.016 kg moisture per kg. of dry air & leaves w/ a relative humidity of 100 % while the temp. remains constant at 600C. If the total pressure of air is 101.3 kPa. dotermine: a. Total required amount of air in kg / hr. under entrance condition b. Capacity of forced draft fan to handle this air in m3 / min. NOTE: at pt.3: @600C. Psat 19.94 KPa & Pv = Psat. HR2 = 0.016 kg w.v. / kg d.a. V2 = 0.9675 m3 /kg HR3 = 0.1524 kg w.v. / kg d.a. O a. 5,200 kg/ hr b. 87.50 m3 / min O a. 4.315.25 kg / hr b. 95 m3 / min O a. 5,315.25 kg/ hr b. 88.70 m3 / min a. 5,315. 25 kg /hr b. 85.708 m3 / min.
JUST NEED QUESTION 2 NOT 1 1. Air at a dry bulb temperature (dbt) of 40 oC and a relative humidity of 30% is heated to a dbt of 80 oC. Using psychrometric chart to determine: a. The change in moisture content per kg of dry air. b. The change in enthalpy from the initial unheated air to heated air. 2. The previous heated air is then conveyed through a humidifier to raise its relative humidity to 25%. Using psychrometric chart to determine: a. The change in moisture content per kg of dry air. b. The change in enthalpy from the heated air to final humidified air. Hint: the humidifier changes the humidity ratio without changing dry bulb temperature.
Moist air enters a duct at 10oC, 80% relative humidity, and a volumetric flow rate of 81m3/min. The air is heated as it flows through the duct and exists at 34oC. No moisture is added or removed. Draw the cycle on the attached chart and determine: a) The rate of heat transfer in KJ/s; b) The relative humidity at the exit.