Issue with analysis period

old forum
1

hi all. I’m running an energy simulation for a room. the results that i get from a simulation for whole year are the same as simulation for period 8-15 hrs. i don’t know why it is happening! anyone have any idea what might be the problem?

Thanks in advance.

SW test.gh (863 KB)

2

Mahdye,

The “error” was that you connected the created zone with the HB_Mass2Zone. This was cancelling the windows definitions and starting the zone creation from the beginning. There is no need, in your case for such connection. See attached.

Didn’t run it but i’m pretty sure you’ll see now the differences.

Also updated the file to the latest version.

-A.

SWtest_AY.gh (654 KB)

3

Thanks Abraham… I updated my HB & LB to the last version, but i get this error for running energy simulation: 1. Solution exception:global name ‘HBGenerators_’ is not defined as picture

I followed the discussion “http://www.grasshopper3d.com/group/ladybug/forum/topics/1-solution-exception-global-name-hbgenerators-is-not-defined” but couldn’t fix my problem.

SW test 1.gh (935 KB)

4

Here you go.

You just needed to reinsert this component as it changed the number of inputs. I reinserted also the 3dChart.

-A.

SWtest1_AY.gh (638 KB)

5

Thanks one again Abraham… I reinserted all the components, but don’t know why it didn’t solve the problem… now with the attachment you sent it’s ok :slight_smile:

As my first problem i still have the same results for both whole year and period analysis 8-15 hrs. i canceled HB_Mass2Zone component, but no change!

6

I see that the zone program you set is OfficeBreakRoom. Being that i suppose there is no difference running the whole year hours or just 8 to 15. Those are probably the occupancy hours. Makes more sense to run just a few months than just some hours,

-A.

7

Mahr,

You only need to reinsert components if the inputs/outputs have changed in the updated version of the component.

For your analysis period question: EnergyPlus is not capable of modeling simulations that are shorter than a day. Therefore, the “hour” inputs on the analysisPeriod component do not have any effect on the Energy simulation component. The deeper reason for this is that the temperature and energy use during a given hour are dependent upon the temperature and energy use of the previous hours. So it is not accurate to run a simulation for the analysis period that you have set.

If you want to get data for just your occupied period in Grasshopper, you only need to post-process the results with the “Average Data” component:

-Chris

SWtest1_AY_CWM.gh (640 KB)

8

Thanks Chris

It was so usefull.