<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><div><span>Hi, </span></div><div><span>I'm am very new at this so please forgive me for stupid questions, simple mistakes, and lack or technical lingo.<br></span></div><div>I'm running two flow case simulations, a turbulent channel and a backward facing step to test a new LES filter. I have run the simulation including the avg_all routine. After completion, several avg.f, rms.f, and rm2.f files were created. I compiled the avgall.usr file and ran again after placing the .f files into respective .list files and ran again in order to get the time averaged data. In the .output file, a bunch of error messages were displayed saying ERROR: Non-positive diffusivity (0.00) specified for field 1, group 0 element. I was told that commenting out the udiff and utrans in the uservp subroutine of the avgall.usr file and also setting the
NSTEPS to 0 in the .rea file would fix the problem, but neither worked. Any advice? <br><span></span></div><div> </div><div>Sincerely,<br><br></div><div>Josh Rabau<br>Mechanical Engineering MS Texas A&M University 2013<br>Mechanical Engineering BS Rochester Institute of Technology 2011<br>603-381-6685<br>josh.rabau@yahoo.com<br>jir2830@.tamu.edu<br></div></div></body></html>