Question

If air at 65 degrees Fahrenheit and 50% humidity enters a furnace which heats the air...

If air at 65 degrees Fahrenheit and 50% humidity enters a furnace which heats the air to 120 degrees Fahrenheit. What is the relative humidity of the air leaving the furnace.

Homework Answers

Answer #1

using the August-Roche-Magnus approximation.

TD: =243.04*(LN(RH/100)+((17.625*T)/(243.04+T)))/(17.625-LN(RH/100)-((17.625*T)/(243.04+T)))

RH: =100*(EXP((17.625*TD)/(243.04+TD))/EXP((17.625*T)/(243.04+T)))

Where, RH = Relative Humidity

T = temperature

Td= Dew point temperature

AT T=120F and RH=50%

Calculating

TD: =243.04*(LN(RH/100)+((17.625*T)/(243.04+T)))/(17.625-LN(RH/100)-((17.625*T)/(243.04+T)))

TD= 45.91F

And now putting TD=45.91F and T=120F, for calculating RH

RH: =100*(EXP((17.625*TD)/(243.04+TD))/EXP((17.625*T)/(243.04+T)))

RH= 9% Answer

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Atmosphric air at 40 F and 50% relative humidity enters the heating section of an airconditioning...
Atmosphric air at 40 F and 50% relative humidity enters the heating section of an airconditioning device at a volumetric flow rate of 100ft^3/min. Water vapor is added to the heated air to increase the relative humidity to 55%. The temperature after the heating section is 72F and the temperature at the exit is 74F. Using the appropriate fomulas: a) determine the rate of the heat transfer in Btu/min. b) determine the mass flow of water vapor in lbm/min.
A humid air stream enters a process at 35 C, 20 atm, and 50% relative humidity....
A humid air stream enters a process at 35 C, 20 atm, and 50% relative humidity. The oxygen flows at 900kmol/h. Determine the molar flow rate of water in the stream.
The air in a building has a dry bulb temperature of 72F and 50% relative humidity....
The air in a building has a dry bulb temperature of 72F and 50% relative humidity. Final dry bulb should be 65F and a relative humidity of 40%. The building is 60’ long, 45’ wide, and has a 12’ ceiling. Find the quantity of water required to raise the relative humidity to 65%
Air at T1 = 32°C, p1 = 1 bar, 50% relative humidity enters an insulated chamber...
Air at T1 = 32°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 A) Determine mass flow rate of the moist air entering at state 2, in kg/min. (Answer...
Moist air at 30 °C and 50% relative humidity enters a dehumidifier operating at steady state...
Moist air at 30 °C and 50% relative humidity enters a dehumidifier operating at steady state with a mass flow rate of 319.35 kg/min. The moist air passes over a cooling coil and water vapor condenses. Condensate (condensed water) exits at 10 °C. Saturated moist air exits in a separate stream at the same temperature. The pressure remains constant at 1 bar. Determine (a) the rate at which water is condensed, in kg/min, and (b) the heat transfer rate during...
In a condenser, humid air at atmospheric pressure, 35 degree celsius and 90% relative humidity enters...
In a condenser, humid air at atmospheric pressure, 35 degree celsius and 90% relative humidity enters the process at a rate of 2.12 m3/s. Liquid water exits as a condensate. If the air exits at 20 degree celsius, determine the molal humidity of outlet air, absolute humidities of inlet and outlet air and flow rate of condensate in L/s.
Air at 95°F, 1 atm, and 10% relative humidity enters an evaporative cooler operating at steady...
Air at 95°F, 1 atm, and 10% relative humidity enters an evaporative cooler operating at steady state. The volumetric flow rate of the incoming air is 1765 ft3/min. Liquid water at 68°F enters the cooler and fully evaporates. Moist air exits the cooler at 70°F, 1 atm. There is no significant heat transfer between the device and its surroundings and kinetic and potential energy effects can be neglected. a)Determine the mass flow rate of the dry air in lb(dry air)/min....
Air from outside (5 deg-C, 50% relative humidity) is heated by an electrical heater to a...
Air from outside (5 deg-C, 50% relative humidity) is heated by an electrical heater to a temperature of 35 deg-C at a mass flow rate of 10 kg/s (dry air). Determine the relative humidity of the conditioned air at the exit
Water freezes at 0 degrees Celsius, which is the same as 32 degrees Fahrenheit. Also water...
Water freezes at 0 degrees Celsius, which is the same as 32 degrees Fahrenheit. Also water boils at 100 degrees Celsius, which is the same as 212 degrees Fahrenheit. (Use fractions in your answers.) (a) Use the freezing and boiling points of water to find a formula expressing Celsius temperature C as a linear function of the Fahrenheit temperature F. (b)This means that for every one degree increase in the Fahrenheit temperature, the Celsius temperature will increase by what degree?
An air-conditioning system with a room design 22 degrees C DBT & 50% RH has a...
An air-conditioning system with a room design 22 degrees C DBT & 50% RH has a room sensible heat 35 kW with 0.8 sensible heat factor. Determine: a. Draw the psychrometric chart indicating all parameters; room condition, SHF, room ADP & all temperatures & humidity b. Room latent heat in kW c. Room apparatus dew point d. Supply cmm of air at the room apparatus dew point. e. Supply cmm and specific humidity for a supply air 16 deg C