[Nek5000-users] Local drag calculation

[nek5000-users at lists.mcs.anl.gov]

Hello Neks,

A question regarding the calculation of drag for y+ calculation at specific points in a domain:

How would one go about altering the approach used in the example cases such as turbchannel, where the drag is integrated over larger surfaces, to only calculate the drag at a single point in the domain?

My simulation pertains to flow through pebble beds, so the drag should be relatively anisotropic over the pebble surfaces, hence the point value approach. My thinking is to find the point in the domain where my line of interpolation begins and then calculating the drag for the element that contains said point, would that be appropriate?

Finally, is it then appropriate to use the dU/dy value for the largest component (I’m assuming it’ll be for the stream-wise velocity component) as the basis for the calculation of the y+ value?

Thanks for any assistance regarding this!

Lambert