[sharif88]

hello all,

basically I want to know you guys opinion about a case,
the case is a turbulent flow over a sand bed, in order to simplify the problem I assume the sand bed is stationary, now here is the thing: can I just replace the sand bed with a rough wall (with roughness height equal to sands size), would a rough wall just do the same as dose a stationary sand bed?
My primary interest is to obtain frictional pressure loss data,

Thank you
Majid