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sakmak
17-04-2014, 04:45 PM
good after noon everybody

I really need your help and expertise, I need to calculate the amount of heat transfer for a vehicle's cabin but I am facing some troubles finding the heat coefficients for the parts such as the roof, windows,......etc. I also need the heat coefficient for the air flowing around the car, is there any tables I can directly take these values from or do I need to make an assumptions and calculate the heat transfer coefficient for the air flow based on its nature ( laminar or turbulent).

please I need your advice and it is urgent, I really appreciate your support.
(p.s. my apologizes for any lingual mistakes)

Peter_1
18-04-2014, 12:24 PM
IMpossibel to calculate, to many variables which you don't know (air infiltartion, fresh/air intake, outside conditions,..). Refer to existing systems for this.

xxargs
19-04-2014, 12:48 PM
Best way is measure on existing vehicle's in same size you calculate on, look on capacity for heating and cooling and be not surprise capacity on heating/cooling can be pretty high.

for standard personal car is cooling/heating capacity can be between 4-7 kW and in cooling case, how much window area take in sun and painting color on vehicle's have big impact how you feeling inside and also cooling demand.

ie driver and passenger sitting in flow of temperature controlled airflow and not caculate so much insulation help from cabins wall and window... and if stops engine, heat or cooling disappear very quickly...

sterl
29-04-2014, 09:13 PM
Gross generalization but:

Radiant Heat Xfer is dominant and the slope of glass and absorption of surfaces below the glass is greatly involved (the greenhouse effect....)