Carb heat

[B Fraser]

the air is moving more slowly

.... so the venturi effect is minimised which should lead to less of an adiabatic reduction in temperature however ......icing is more prevalent at low power which is surprising. I think Dubtrub may be right in that the butterfly valve is the restriction that leads to icing at low rpm i.e. the valve has a small aperture leading into the main body of the carb.

happy landings

B

[High Wing Drifter]

Yup Dubtrub's makes sense. But much of the cooling is due to fuel vapourisation, not just the venturi. As fuel is being vapourised at the same pro-rata rate...