Fluent 5 post processing matter: I am trying to compute the power used by a vibrating plate on moving the fluid above it using fluent 5. One approach I have is to integrate an appropriate custom field function using surface integrals under the reports menu. Does any one have a better way or an improvement to my idea?

Hi Amadou,

Either a CFF or a UDF utilizing the execute on demand macro would work. The latter approach with the UDF would give you more flexibility particularly if the plate is non-planar and you can also write the function to user-defined memory so that you can display contours of the power on the plate. A simple alternative would be to use the Report->Forces... panel to compute the force on the plate and then hand- calc to power.

Cheers, Lanre

Hi Lanre, Thanks for your input. The force on the plate is not constant so the last option (Report-->Forces) is not as applicable as the first two. The CFF approach is the one I am using currently.

However, your second approach would be really good to do since I can plot contours of power on the plate. Unfortunately, I am not familiar with this approach. I will be more than glad to know the specifics on using a UDF to achieve this task.

Hi Amadou,

This example walks you through the basics of my second suggestion:

http://www.fluentusers.com/fluent5/d...ml/node108.htm

You'll need to compute the shear stress on the plate (wall) zone to use in the power calculation.

Cheers, Lanre

Thanks Lanre, I will pursue it.