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Automotive Radiator Sample Calculations Help

  1. Nov 6, 2015 #1
    Hi all,

    As part of a school project, I'm attempting to demonstrate some sample calculations of a car radiator and I'm a little lost. I'd like to demonstrate some cooling requirements for the peak power output of my car engine: 325 horsepower at 4400 RPM.

    Can anyone offer any guidance as to how to obtain sample values for the max conditions:
    Typical inlet and outlet coolant temperatures?
    Coolant volumetric flow rate?
  2. jcsd
  3. Nov 6, 2015 #2


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    To be honest, I think you need to find another project. The problem with your proposed project is that the cooling of the engine is based upon the residual heat transfer to the engine assembly of that part of the combustion heat that is not removed by the engine exhaust gases. So there is no good way to determine how the removal of that heat is split between the exhaust discharge and the engine's cooling system.

    Automobile engine cooling systems are designed to be able to remove more heat than is required to maintain the desired engine operating temperature under the anticipated worst case operating conditions and then a temperature sensitive thermostat controls the coolant flow rate through the system to maintain the engine at the desired operating temperature regardless of the variations in ambient air temperature or engine horsepower being generated at any given time.
    Last edited: Nov 6, 2015
  4. Nov 6, 2015 #3
    Thanks for the reply.

    This project is actually part of a larger project involving the restoration of a car. As just a small part of it, we'll be ordering a new custom radiator to mate with his engine. In reality, I'll be leaving the radiator designing and building to the pros at a custom rad shop. In the meantime, we're writing reports and I've been asked to perform some type of engineering / quantitative analysis to keep in mind for rad selection. So really, I'm looking for any type of quantitative analysis or relevant equations to convince my professors I know what's going on in the radiator. Sort of lost as to what direction to take. It doesn't need to be very involved, it can be general stuff.
  5. Nov 7, 2015 #4


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  6. Nov 7, 2015 #5


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