Graham,The first step is to pick the heat exchanger model that best fits your drain water heat recovery device. Then you'll have to create the hot water draw profile AND the drain water profile. These should be different profiles as things like baths and clothes washing do not have coincident supply and return water flows. You may also have to account for the cold water draws/dumps depending on the location of your heat exchanger. I would avoid Type 14 forcing functions and instead rely on the Type 9 data readers or even the new Event-Based Data Reader from TESS to drive the flows through the system. I've done a few of these drain water heat recovery models and the key is getting the flow rates right. The Building America program has a utility for creating event-based draw profiles - you may want to start there.
Jeff --- Jeff Thornton President - TESS LLC 22 N. Carroll Street, Madison WI USA 53703 Office: (608) 274-2577 Fax: (608) 278-1475 www.tess-inc.com E-Mail: thornton@tess-inc.com On 09/11/2012 11:47 am, Graham S. Wright wrote:
I would like to use TRNSYS to model drain water heat recovery, if there are suitable components. How should I approach this ? The focus is residential (single and multi-family). The output I am looking for is basically the annual average increase in the temperature of the incoming cold water, post-recovery. On a related note, I think I remember seeing somewhere on the internet that some in the US had put together a detailed hot water draw profile with thousands of events that required six-second time resolution. Does this ring a bell and if so how would one get that into a TRNSYS schedule ?