1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Ideal vapor-compression

  1. Apr 13, 2015 #1
    1. The problem statement, all variables and given/known data
    A refrigerator uses R-134a as the working fluid and operates on an ideal vapor compression refrigeration cycle between 0.15 MPa and 1 MPa. Mass flow rate is 0.05 kg/s. If a minimum of 5 deg-C difference is used in the condenser design for effective heat transfer, what is the maximum value of the atmospheric temperature under this operating condition?

    2. Relevant equations

    3. The attempt at a solution
    No idea. Wouldn't it not matter since its atmospheric temperature? Or would it be the lowest temperature in the cycle?
    Last edited: Apr 13, 2015
  2. jcsd
  3. Apr 13, 2015 #2


    User Avatar
    Science Advisor
    Homework Helper
    2017 Award

    The working fluid has to evaporate at the lower pressure and to condense at the higher pressure. The saturation temperature at the higher pressure has to higher (by five degrees as specified) than the ambient temperature. That sets an upper limit to the ambient temperature !
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted