SIMPLE code is in teh original paper by Patankar, I beleive.
I thought SIMPLE was the name of the method Patankar conrtructed for
heat transfer problems which was followed by SIMPLER. Anyway, there are
people here who use a method called SIMPLE by Patankar and I will
check to see if there is a code by this name and post it next time. Either
way now Patankar has gone commercial with his own company and the
codes they now have in the market is called CONDUCT.
I will post the details. But his book is definitely a good place to
look in.
Ragu