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Kevin Yeo
22-07-2005, 04:49 AM
Size of Coldstore 46.2 x 11.6 x 16mH. Room temp +2 deg C.
I'm using 5 x Guentner evaporator GHF050.1E/47-ES.
Air volume of each unit cooler is 25760 m3/h. Q is 46.3 kW @ -8 deg C/ 45 deg C SST/ SCT.

Volume of room 8575 m3.

Can someone offer some suggestion on how much air volume should unit cooler per cubic room size.

frank
22-07-2005, 08:39 PM
Size of Coldstore 46.2 x 11.6 x 16mH.

Is the room really 16m high? :eek:

botrous
22-07-2005, 08:51 PM
What's that 16 m , that more than a 5 stories heigh . . . .

frank
22-07-2005, 08:54 PM
Nearly 50 ft Botrous

Peter_1
22-07-2005, 09:54 PM
The biggest freezer we did was +/- 60 x 30 x 11 m.

Kevin, you don't have to worry about the needed air volume versus the volume of the room.
You calculated the needed capacity and installed it. The manufacturer of the evaporators has done his job and limited the airflow over the evaporator coil to avoid water blowing of the coil.
What we do if we need more air circulation like you find in a blast freezer, blast chiller or in the larger fresh meat storehouses when they enter the fresh carcasses is mounting some additional room ventilation with axial fans.

Especially because you're room is evry high, I should look if you don't have stratification of the air (different temperature layers in the height)
You could install on the opposite side of the evaporators fans which are blowing downwards.

Are the stored products fresh products who needs some basic minimum air circulation and are they brought in the room already at room conditions.

I suppose they also installed very high racks in it - maybe automatically controlled sliding racks - so you could think of blowing the wind in the open spaces between the racks.
We installed in a freezer the evaporators lined up with the open spaces between the racks so that the air blows in this open spaces.

Install some thermometers and verify if you have stratification and if so, adjust the bulb of the temperature controller.

I will have a look in some industrial Refrigeration books I have tomorrow and if I find something about this topic, I will post it.

botrous
22-07-2005, 10:28 PM
Nearly 50 ft Botrous

I know frank , i was just comparing the 16 m to a building height

Kevin Yeo
23-07-2005, 02:50 AM
Dear all,

Yup, the height is 16 m. However, i'll discuss with the owner reg the possibitily of reducing the height to around 12 ft [40 ft] due to constraint in transporting insulation panel. In Malaysia, normally we do 40 ft height max.

Thanks for your advise Peter, air streamer would definitely be used to reduce turbulence of air. As I'm using 5 unit blowers, i'm thinking to install the unit coolers 3 on left and 2 on right panel, staggered. Do you think it can improve air ventilation and reduce hot air pocket? And by this, 2 main line [suction & liquid] would be run. 5 blowers shall have individual thermostat that linked to one pc gateway for control and monitoring.

I'm in fact thinking bout defrosting of the system. 3 x 60 Hp screw compressors would be used. In this scenario, how do you guys suggest defrosting be done. Is there better ways to electrically defrost it not in same time? Guess not right...Pretty heavy starting current...