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kfjoe
14-07-2010, 06:44 PM
Hi all

I wonder if someone could help me with the following question please:

If i have a Blast Freezer which is a certain room size and I then increase the room size (say length), but the product load stays the same what would be the effect of this ?

i am guessing my refrigeration duty of the kit would still be the same as the volume of air through the evap coil would be fixed by the fans, but the extra volume of air would reduce the air changes? if it was only the length of the room that was changed this wouldnt effect air speed?
But how would this effect my reduction of product temperature ??

any help or guidance welcome

thankyou

icecube51
14-07-2010, 06:57 PM
I think you have to look for what yore room was designd for in the first place.
did it needed a specific temperatuur on a designd time? is yore product already in a slightly froozen state, ore is the room designd to freeze the product on a specific time?

making changes to a coldroom or freezer is something that takes serius consideration before applying.

Ice

kfjoe
14-07-2010, 08:11 PM
thankyou for the response
unfortunately i do not have that information, I only have the duty of the kit etc, and know that it will reduce the temperature of a certain amount of product in a time succesfully as it is doing it now, this product load weight and temps etc will not change but the size of the physical store will and im confused as to what effect this will have , obviously heat infiltration etc will be bigger but i would think this is very minor in comparision

RANGER1
14-07-2010, 08:42 PM
As long as there are no short cuts of the air between product , above , around etc shoul be the same I think .

Basically product should be packed as before .

kfjoe
14-07-2010, 08:48 PM
thanks for reply

If the room was wider and therefore cross section was larger i am guessing the velocity would reduce, so my other question is if i reduce the air speed over the product i would reduce the rate of heat removal ??

oldesky
15-07-2010, 03:14 AM
Any extra bypass air will lengthen the freezing process. The extra size will increase the wall transmission load but if the size increase is small it should have little if any effect as the load of the product is generally a much higher percentage of the total load.