1. Not finding help here? Sign up for a free 30min 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!

Heat exchanger problem in Thermodynamics.

  1. Nov 25, 2010 #1

    I get the basics now, but this problem has got me stumped. I am trying to figure out where to start.

    1. The problem statement, all variables and given/known data

    In a heat exchanger, cold water flows through the tubes of the exchanger. It enters at 5.5°C, and leaves at 65°C. In the shell of the exchanger steam is being condensed. The steam enters at atmospheric pressure and 100°C, and the condensate that is formed leaves the exchanger before it can be cooled. The flow rate of the steam is 15.0 kg/s. What is the cooling flow rate?

    2. Relevant equations

    Oil flows through a heat exchanger at a flow rate of 125 L/min. It enters at 20°C and leaves at 75°C. The oil has a specific heat of 2.84 kJ/kgK and a relative density of 0.8. The oil is being heated by steam. The steam enters the heat exchanger at 100°C and the condensate formed leaves the heat exchanger at 85°C. Calculate the mass flow rate of the steam.

    3. The attempt at a solution

    First thing we know is that cool water flows through the tube, and exits as warm water. In the shell, steam is being condensed. So basically water turns into steam.

    Q (cool water absorbing heat) becomes hot water.
    Q = mcΔt + mLv + mcΔt (water becomes steam)

    The idea is solid, but I am not sure how I take the above, and find the flow rate. For all I know, those two are different categories.

    Thank you for your help. I am this close to finishing up the course, so stumbling at this point does hurt, but the help which I receive will mean a lot to me.
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted

Similar Discussions: Heat exchanger problem in Thermodynamics.
  1. Thermodynamics problem (Replies: 0)

  2. Thermodynamics problem (Replies: 0)