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amaryta
06-09-2006, 02:03 PM
could u help to design this water cooler:

*Storage temp 10 c
*Inlet of water Temp 40 c

I want to know how to estimate the load (transmission & water) of 2 gallon of water

autt
06-09-2006, 02:24 PM
You need to give more parameter as both sides flow, temperature, load to design the chiller, and more info to estimate the load

NoNickName
06-09-2006, 02:39 PM
In order to cool 2 US gallons of water (7.57 liters) or 2 UK gallons of water (9.09 liters) from 40C to 10C you need 1 Kcal/Kg approx

Case 1) 7.57 Kcal/C or 30 BTU/C
Case 2) 9.09 Kcal/C or 36 BTU/C

dt = 30C then

Case 1) 227.1 Kcal or 900 BTU
Case 2) 272.7 Kcal or 1080 BTU

Note this is not cooling capacity: this is ENERGY

amaryta
11-09-2006, 04:37 PM
*The water cooler is for drinking.
*This tank will be a product tank or Per cooling tank and it will supply Another tank to be stored there.
*The comressor run time is 1/2 hour.
*Desine ambient temp is 46 C 115 F.

My questions are:
1-Will i calculate the transmission heat if it is insulated with fiberglass insulation .
2-How i will select the equipments

NoNickName
11-09-2006, 07:50 PM
First of all add the heat gain from ambient, considering your insulation.
Then you have to consider the hourly water consumption.
Then the desired chilling time must be considered as well.

botrous
11-09-2006, 10:45 PM
*
My questions are:
1-Will i calculate the transmission heat if it is insulated with fiberglass insulation .


Hi amaryta , first of all you must choose the thikness of the fiberglass , let say you want a heat transmission of X w/m^2 , you do the calculation and you will have a thikness , if the calculated thikness Y doesn't exist on the market you choose the closest and you do a reverse calculation to see what the new transmission is X' w/m^2 and so on you continue your calculation.

Remeber insulation will not draw the heat transmission to zero.

Respects and regards
Botrous

botrous
11-09-2006, 10:56 PM
could u help to design this water cooler:

*Storage temp 10 c
*Inlet of water Temp 40 c

I want to know how to estimate the load (transmission & water) of 2 gallon of water


*The water cooler is for drinking.
*This tank will be a product tank or Per cooling tank and it will supply Another tank to be stored there.
*The comressor run time is 1/2 hour.
*Desine ambient temp is 46 C 115 F.

My questions are:
1-Will i calculate the transmission heat if it is insulated with fiberglass insulation .
2-How i will select the equipments

First of all calculate the need to cool the water from 40 C to 10 C.
Q=m * c * deltaT
m = mass of water to be cooled
c = thermal coefficient of water
deltaT = T_entry - T_exit
Q= the ammount of energy you need to substract from the water

then do the heat transmission of the tank (it depends of the time you want to store the water in at T=10C)

If you need accurate results you should also calculate the heat transmission over the pipes.

We need more details to give you details on how to calculate the compressor capacity. maybe a sketch drawing of your design will help.

Respects and regards
Botrous