Results 1 to 3 of 3
  1. #1
    Join Date
    Apr 2013
    Location
    England
    Posts
    41
    Rep Power
    0

    Question Does a refrigerator work better when room temp is increased????



    Hello,

    If i change ambient temp by 1 deg higher in my equation i get these results:

    QL1 = 9639.85W; Win1 =3069W; QH1 =12708W

    If I change ambient temp +1 = 25+1 degs C. and i do not change Refrigerator temp = 3deg C (unchanged), i get:

    QL1 =9392.37W; Win1 = 2990W; QH1 =12382W

    Ql=evap.
    Win=Compressor
    Qh=condenser.

    So I am increasing ambient temp (room temp) by 1 deg. and keeping the refrigerator the same temp. I get reduction of evaporator heat transfer, compressor work input and also QH. COPis the same as the reductions are proportional to each other. I understand that heat flows easier where there is a bigger temp difference but still didnt expect all reductions.

    Is this equation i'm using sane or insane? in respect of these results?

    Please help, thank you



  2. #2
    Join Date
    Feb 2007
    Location
    UK
    Posts
    2,479
    Rep Power
    45

    Re: Does a refrigerator work better when room temp is increased????

    Looks like if there is a problem with your calculations somewhere...

    Normally you would expect the work for the compressor to increase with an increased pressure differential.

    It would be easier to comment if you also posted your calculations.



  3. #3
    Join Date
    Mar 2006
    Location
    Lancashire
    Posts
    1,876
    Rep Power
    28

    Re: Does a refrigerator work better when room temp is increased????

    Increasing the ambient temperature and in turn the condensing temperature of your refrigeration systems will cost between 2% and 4% for every 1°C increase in condensing temperature.
    This will increase the compression ratio and lower the volumetric efficiency and so your equation isn't quite right.

    Edit..... Just re-read your post and you say a 1degC increase in room temp. If that is the case then your SST will change, your power input will increase, your COP will increase as well as your heat of rejection.
    Last edited by marc5180; 30-08-2013 at 10:09 PM.
    The difference between genius and stupidity is that genius has its limits.

    Marc

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •