<https://forum.tuflow.com/index.php?/topic/2027-pipeflow-not-returning-to-0/#comment-4869>
<http://schema.org/text>
"Hi Josh,\n \n\n\n\tIt sounds like it could be a mass balance issue in ESTRY.\n \n\n\n\tWhen you run on GPU, you're normally pushed into running single precision, and sometimes that's not quite good enough. This could be on one of those times. You can test for this easily enough but simply running you model with the double precision engine and see if it comes out different! You'll need to add the command \"GPU DP Check == OFF\" to run this on GPU.\n \n\n\n\tAnother possibility is that you need to run with a smaller ESTRY timestep (which would again manifest as mass balance problems). If you've got small elements then your timestep needs to be smaller. Often ESTRY timesteps seem to be a neglected consideration, and set at 1 (default) and ignored. You may very well need to go smaller.\n \n\n\n\tFinally though, are you sure it's not correct? A small trickle slowly draining off such an area would accumulate through a pipe network into something non-negligible.\n \n\n\n\tI'd start by looking at your mass balance outputs and see if there's anything untoward in there. Let us know how you get on, I'm sure other folk are likely to run into similar and would like to know the outcome!\n \n\n\n\tPHA.\n \n"
<https://forum.tuflow.com/index.php?/topic/2027-pipeflow-not-returning-to-0/>