Perforated plate

[wkramer]

Hello,

Say I have a cold medium flowing through a channel with an electrically heated perforated plate obstructing the flow.
Does anyone have an idea on how to calculate the heat transfer coefficient between perforated plate and cold medium?

Thanks,

Walter Kramer

 

[poetix99]

You could simply measure the electrical consumption of the heater. A simple energy balance (if you know the fluid flow and bulk properties) would imply the downstream temperature of the fluid. You could, if it's important, refine this in order to account for downstream losses through the pipe walls.

Otherwise, you'd have to consider the fluid flow through the plate, and come up with averaged values of heat transfer coefficient. And you wouldn't necessarily know the temperature of the plate anyway.

Some of the pertinent parameters that MIGHT effect the h.t.c. are: the bulk fluid proerties and upstream velocity, the amount of open area in the plate and the nature of the holes, the ratio of hole diameter to plate thickness,... You'd have to wade into the problem before being able to determine which of these things actually matter for your application.