Heat flow summation for calc period

John Wright · Post by **John Wright** » Mon Sep 24, 2007 3:56 am -1100

Is there a field that calculates the sum of the energy used to maintain interior conditions over the time period of the run. That is, is there a sum of the absolute value of the energy flow through the interior wall. I would like to compare the energy used with two types of wall systems throughout a heating/cooling season.

Manfred Kehrer · Sun Sep 30, 2007 4:20 pm -1100

Dear John,

the Interior Heat Flux [W/m²] should be the appropriate results for you.
Just integrate this value over the whole calculation period and you will receive the total Heating Energy.

If you have an calculation timestep of one hour just sum all hourly result values of the interior heat flux and you will receive the total Heating Energy in Wh/m².

John Wright · Post by **John Wright** » Mon Oct 01, 2007 2:52 am -1100

Once a project is run, in the basic screen: Status of Last calculation found by clicking on the icon bar at the top the "Status of Last Calculation" icon. There are two lines: Integral of fluxes, left side and Integral of fluxes, right side (kr, dr {lb/ft^2}. This sounds like what we are looking for, but the units are not the same. Defined in help as the total amount of water which flows into or out of the component during the calculation.

WUFI-pro 4.0 (e) Online Help

So I thought "perfect" this aught to be it: the sum of fluxes for the whole year period I ran on this simulation, but no this is moisture. I was hoping I could get some help from the program to sum the heat flows. I am sure you understand the problems: sum for a year of data points, might be a lot of work.
Thank you for the rapid response: I asked the question because I believe that somewhere in the data is the answer already calculated and I assumed I don't know where to look. If you know where I might found this integral of fluxes: heat flow, that would really be helpful, and your answer is absolutely correct in my view, I am just hoping the computer could do the grunt work.

Manfred Kehrer · Mon Oct 01, 2007 3:06 am -1100

Sorry for my insufficient answer.

WUFI 4.1 can do it. There are the Integral of the Heat fluxes left and right listed [MJ/m²]. Unfortunately the help file does not yet explain it, but it is self-explanatory. We will improve the help file in the next release.

Best Regards,

John Wright · Post by **John Wright** » Mon Oct 01, 2007 9:09 am -1100

Wow, you really nailed that one for me. I must truly thank you. I found it and have printed out the screen captures.
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Heat flow summation for calc period

Heat flow summation for calc period

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