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ORC for waste heat recovery in cars

  1. Oct 5, 2008 #1
    hi there....to all the enthusiastic people of thermodynamics/thermal engineering. I am working on a project to recover the exhaust heat of a car,for which i require a great amount of guidelines from ur side.firstly,I am not sure as to howmuch of heat is wasted through the exhaust. Do u think i can use a primitive method which uses a water jacket(small dia pipe encircling atleast half the portion of the exhaust pipe)and find the mass flow rate and temp rise .I am not sure about the accuracy. Could u suggest some other method to measure the amount of heat rejected through exhaust.
    Secondly,do u think the exhaust heat is simply sufficient to run a compressor of the cars airconditioning system.


  2. jcsd
  3. Oct 5, 2008 #2


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    Heat rejected to exhaust is found out by measuring fuel mass flow into the engine, air mass flow into the engine, exhaust temperature and ambient temperature. Just do a simple heat balance.

    I doubt the heat you are able to recover would be sufficient to run air conditioning; you need air con just as much while the engine is idling.
  4. Oct 6, 2008 #3
    Is there any other way in which we can use the exhaust heat other than turbocharging???
    I feel the thermal efficiency of the engine can be increased to an greater extent by converting the heat from the exhaust into useful work.
    Last edited: Oct 6, 2008
  5. Oct 6, 2008 #4
  6. Oct 6, 2008 #5


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    Sure, you could pass water through it and you'd have some warm water which you could clean your windows with. Or you could put a thermopile on it and power the LCD panel for the stereo. Or you could put a turbine in it, and use this to drive a compressor...
  7. Oct 6, 2008 #6


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    About the only thing, and I am sure this has been tried, is to use it to heat the incoming fuel. On our engines it's a good thing, but we don't run gasoline. I can't imagine anything really useful you could do with it.
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