Hi all, Anyone can send me some experimental and/or numerical data concerning a backward facing-step laminar flow (Re vs reattachment distance).

Thanks a lot

Try the ercoftac data base it contains the DNS data for the paper 'Direct Numerical simulation of turbulent flow over a backward-facing step' by Le et al.

Stephen

I find one paper:"Simulation o fturbulent flow over a backward-facing step" J. Fluid Mech, 1997, vol.330:349-374

http://ercoftac.mech.surrey.ac.uk/dns/homepage.html

maybe you can get some useful information from the web site.

Sophie, I wrote a FORTRAN program using finite volume method staggered grid pressure correction with SIMPLE algorithm as part of my cfd msc. The total pipe lenth was 171 units long (in the x direction). It expanded from 10 units (in the y direction) to 20 units (via a one sided step like the one you mean) at a distance of 20 units in the x direction. The fluid was water and it entered the pipe with a parabolic velocity with maximum in centre of 1.5 units per sec. The reatatchment distance was at about 64 units in the x direction (this is 64-20=44 units past the step).

Please say if my explanation of the Geomerty is rubbish. I will try again if you wish.

Good luck, Rat.