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Convection Coefficient?

Luis Aguirre

New member
Hello Hammerpe,

The values for the convection coefficient also known as the film coefficient are Btu/(hr*ft^2*F) or W/(m^2*K). Adding fins will definetely help to disipate more heat. If you still having problems later on post them I will see If I can fix them.



New member

It sounds a little as if you have a units problem. You need to use consistent units throughout. Depending on your chosen units system, you need to make sure all parameters are in appropriate units; eg:

SI Metric:

Heat: Watts (or Joules/second)

Heat Flux: Watts/square metre

Temperature: Degrees Kelvin

Thermal Conductivity: Watts / metre / degree Kelvin

Specific Heat: Joules / kg / degree Kelvin

Convection: Watts / square meter / degree Kelvin

Inch / Pound / Second:

Heat: BTU

Heat Flux: BTU / second /square inch

Temperature: Degrees Fahrenheit

Thermal Conductivity: BTU / second / inch / degree Fahrenheit

Specific Heat: BTU / pound / degree Fahrenheit

Convection: BTU / second / square inch / degree Fahrenheit

Foot / Pound / Second:

Heat: foot . pound force

Heat Flux: foot . pound force / second /square foot

Temperature: Degrees Fahrenheit

Thermal Conductivity: foot . pound force / second / foot / degree Fahrenheit

Specific Heat: foot . pound force / slug / degree Fahrenheit

Convection: foot . pound force / second / square foot / degree Fahrenheit

Note that you may need to adjust the


New member
Hi all

I know this was all started a long time ago but I have recently been doing the same sort of thing. I've been looking for a realistic convection coefficient for forced convection in air and have come across the info above.

Do you have a reference for the above values so I can quote them in my report or details or link to where I can find them?