heat transfer coefficient; melting snow and ice

[EngForm78]

I am working on a problem that involves heat generation to maintain the melting of snow and ice. Would it be correct to use a film coeficient of water at a constant 0 degree C temp. With this method I will be neglecting air temp less than 0, my worst case condition is around -40 C.

Thanks in advance

EngForm78

 

[IRstuff]

Should consult SAE AIR 1168 v4. It discusses deicing of aircraft, so much of what you need is there.

TTFN

 

[EddyC]

I used 33F when I designed a snow melting system for a parking lot. This is what was recommended in the ASHRAE HVAC Applications Handbook.

 

[IRstuff]

Should have been vols 1,2,3,4. Your biggest problem is NOT the heat trasnfer coefficient, per se, but how much wind and wind chill you might expect. That will trump the interfacial stuff.

Bottomline, if you can't get access to the SAE documents, is that you need something like 1 w/in^2 to 2 W/in^2 for a moderate wind and moderate deicing time. Volume 4, Table 3F-3 on page 41, shows power values up to 4 W/in^2 for 300 kt air speed, which, hopefully is outside of your application.

TTFN