Re: [TRNSYS-users] modeling GSHP for DHW using TRNSYS

Everything that the heat pump model needs is input either in an external data file or as a parameter to the model. The example/default data file is from an actual heat pump so the very simplest thing to do is to change the capacity and power consumption parameters in the Type927 proforma and leave the default data file alone. If you have a specific heat pump (manufacturer, model#, etc.) that you want to use then you'll need to go to the manufacturer's website and get the heat pump's performance data. These will be tables that give the heat pump's capacity and COP as a function of entering water temperature, air flow rate, etc. You will need to take the manufacturer's data tables and put them into the format that Type927 requires. You will also need to "normalize" the data. That means that once you put it in the Type927 format you will divide each capacity value by the heat pump capacity at rated inlet conditions and each power consumption value by the power consumption at the rated inlet conditions. Essentially the Type927 data file contains a set of multipliers on the rated capacity and power consumption (which are taken as parameters in the Type927 proforma) and which allow the model to account for how the heat pump performs when the inlet conditions are not at the rated condition.

Hello everyone,

I have TRNSYS18 and as I am getting closer to complete my first model utilizing the program, I have a few questions that could not be answered utilizing search engines on the internet.

The model is basically a GSHP utilizing type 927 (water-water HP), type 534-NoHX (storage tank) and type 557a (GHEX) + pumps, etc ,etc...

My questions are:

1- How can I create the Heat Pump performance data? I already read both Tess and TRNSYS documentation files but they do not explain properly what are the steps necessary to create the performance data file. If what I understand is correct, I just need to change the source and load entering temperatures at the file and the maximum rated capacity and power INSIDE trnsys? or all those must be changed within the data file? I can't find the rated capacity and power inside the data file.

2- I received the file for DHW demand in kWh. What is the best way to evaluate my system and match its size accordingly?

Thank you everyone,

Vitor

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