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Psychrometric Chart Question - Need some guidance!

Pac1Man · 2011-11-13 21:50:22

Hi, I have been given this question to solve but after about 3 hours of googling and note searching I am still at a loss. I know it may be hard for people to answer this post as the question involves plotting points on a psychrometric chart. Basically if someone could guide me towards the order in which to answer the…

13-11-2011 09:50PM

#1
Pac1Man

Registered Users, Registered Users 2 Posts: 4,407 ✭✭✭

Join Date: November 2006

Posts: 4371
Hi,

I have been given this question to solve but after about 3 hours of googling and note searching I am still at a loss. I know it may be hard for people to answer this post as the question involves plotting points on a psychrometric chart. Basically if someone could guide me towards the order in which to answer the question or even point me towards a suitable website it would be most appreciated. Thank you!

Here is the question:

There is a room of 4m x 4m.
Using a figure of 100 watts sensible heat gain and 20 watts latent heat gain per metre squared of floor area (summer design), determine the sensible and latent heat gains for the room.
The room is to maintained at 20 degrees celcius dry-bulb at 50% relative humidity.
Outside air is 30 degrees celcius dry-bulb and 25 degrees celcius wet-bulb.

Supply air is set at 14 degrees celcius dry-bulb.

Cooling coil contact factor is 0.85

Carry out a summer equipment calculation to determine the cooling coil and reheat coil loads for a CAV system to serve the room, clearly showing the process on a psychrometric chart.

The calculations should be done forr:
(a) An all fresh air system
(b) A system with 30% recirculated air

What is the total percentage energy saving by using the recirculation system?
Would the percentage financial savings be the same as the percentage energy savings?

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