https://communities.bentley.com/products/building/performance/f/hevacomp-forum/115216/how-is-volume-flow-rate-calculated-in-netsysWe have a modelled system in Hevacomp which has a cooling load of 16,065 kW and a delta T of 8.4 deg C. Hevacomp calculates the volume flow rate to be 421 l/s. How does Hevacomp calculate this and what value does it use for the specific heat capacityen-USTelligent Community 12https://communities.bentley.com/thread/355591?ContentTypeID=1Mon, 08 Feb 2016 08:42:20 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:4989d8aa-e3df-4a52-9e13-1beefc9ca107Duncan BrownFor reference, the issue here was misinterpretation of data. Thomas was using the emitter schedules to derive the total load from the emitters on the layout, but wasn&#39;t aware that the emitter schedules include all emitters on a floor even if they are not connected. Checking the data showed that a number of emitters where placed in isolation and not connected to the system. This accounted for the (approximately) 10% difference in results and expected results. In this case mains losses were so small to have a negligible effect.<div style="clear:both;"></div>https://communities.bentley.com/thread/353532?ContentTypeID=1Wed, 20 Jan 2016 09:31:52 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:769e9d10-25b5-472b-9740-d7f0d5e03c13Duncan BrownThomas - I think I&#39;d better take a look at the project. Can you PM me so we do that?<div style="clear:both;"></div>https://communities.bentley.com/thread/353529?ContentTypeID=1Wed, 20 Jan 2016 09:20:57 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:20fdacca-59a9-4c9a-b7a6-20b7b81fb7b0Thomas NuttFlow temp: 4.8 <br /> Return temp: 13.2<br /> Surrounding temp: 25<div style="clear:both;"></div>https://communities.bentley.com/thread/353396?ContentTypeID=1Tue, 19 Jan 2016 13:59:35 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:d71d7a59-8010-4ca6-9cd5-e8ead4cef76fDuncan BrownThom - Further to the comment above <br /> <br /> Can you let me know your flow and return temperature at the system marker, and also the surrounding temperature that is set for the project?<br /> <br /> Regards,<div style="clear:both;"></div>https://communities.bentley.com/thread/353390?ContentTypeID=1Tue, 19 Jan 2016 13:30:37 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:7e56b3c1-64b8-4669-9a2d-f3aaf390b6ceDuncan BrownThomas - the example in the document is showing a heating system where you are likely to lose temperature through the mains. In a chilled water system you are likely to gain temperature through the mains, which would show the reverse of what the document shows.<br /> <br /> The document explains the methods used for volume flow rates.<br /> <br /> Regards,<div style="clear:both;"></div>https://communities.bentley.com/thread/353387?ContentTypeID=1Tue, 19 Jan 2016 13:17:20 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:5c7faffd-24db-478a-a321-b209e9f5dca1Thomas NuttThanks for your quick response again Duncan.<br /> <br /> Yes so wouldn&#39;t the figure be larger not 10% smaller?<br /> How does Hevacomp calculate the volume flow rate?<div style="clear:both;"></div>https://communities.bentley.com/thread/353384?ContentTypeID=1Tue, 19 Jan 2016 13:11:44 GMT6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:b6cd9654-1a9b-46da-be19-da57cbf2ff25Duncan Brown<p>Thomas - you need to consider that there will be mains losses - or possibly gains with CHW - to consider as well.</p> <p><a href="/products/building/performance/w/building_performance__wiki/2487.lphw-and-chw-mains-loss-calculations">This document</a> explains this process.</p> <p>Regards,</p><div style="clear:both;"></div>