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WUFI Simulating Weather Data

Posted: Tue Nov 07, 2017 5:26 am -1100
by Alina0826
Hello :

I have three questions related to WUFI simulating weather data:

1. Weather Data read from file: In this case, if I only import one-year weather data into WUFI, but the simulating period set to for example three years. Will wufi repeat the import weather data to three year?

2. Weather database: Weather data in database is real data for every year? What's kind of data built-in WUFI.

3. WUFI result (for example: MC): It always has a strong vibration at the beginning of the simulating period, and become stable after sometimes. What cause this phenomenon? Weather data?

Look forward to your response.

Thanks!

Re: WUFI Simulating Weather Data

Posted: Tue Nov 07, 2017 5:50 am -1100
by Manfred Kehrer
Hello Alina,
1. Weather Data read from file: In this case, if I only import one-year weather data into WUFI, but the simulating period set to for example three years. Will wufi repeat the import weather data to three year?
Yes, WUFI will read the same climate file over and over again. I presume you talk about WAC format. Be sure the data are starting with Jan 1st. 1 am, hourly and contain 8760 datalines.
2. Weather database: Weather data in database is real data for every year? What's kind of data built-in WUFI.
Depends on which country: For USA, Real data for one year are built in. Selection are 10% warm and 10% cold year out of a 30 year period. ASHRAE labeled climate files please look up ASHRAE RP1025
WUFI result (for example: MC): It always has a strong vibration at the beginning of the simulating period, and become stable after sometimes. What cause this phenomenon? Weather data?
If you use the same climate file over and over again you necessarily will end up in a stabilized yearly condition at some point.

Kind Regards,

Re: WUFI Simulating Weather Data

Posted: Wed Nov 15, 2017 6:25 am -1100
by Alina0826
Hello Mr.Manfred

Thank you very much for you reply!

Just for Quota 3, I still have question.
I can see the stabilized conditions you described. But I cannot understand the vibration at the beginning of the simulation, especially after I set the initial condition using real-time data.

I want to ask why it has the vibration from very beginning for most of models. Could you please explain the principle for that?

Thanks again for your help!

Re: WUFI Simulating Weather Data

Posted: Wed Nov 15, 2017 6:29 am -1100
by Manfred Kehrer
If you use the conditions at end of calculation (=stabilized) as the initial conditions, you won't see the vibration

Re: WUFI Simulating Weather Data

Posted: Thu Nov 16, 2017 9:48 am -1100
by Alina0826
Thank you for your help!

Re: WUFI Simulating Weather Data

Posted: Tue Dec 05, 2017 10:07 am -1100
by Alina0826
Hello,

I have a further question.

How to understand "10%-coldest and 10%-warmest year out of a 30 years period"?
It will combine the weather in different years? If so, which month uses 10% coldest year data and which month uses 10% warmest?

Thank you very much!

Re: WUFI Simulating Weather Data

Posted: Tue Dec 05, 2017 10:57 am -1100
by Manfred Kehrer
You just rank the 30 years by average temperature and and take the 3rd and 28th

Re: WUFI Simulating Weather Data

Posted: Wed Dec 06, 2017 12:01 pm -1100
by Alina0826
Thank you for your reply!

I still cannot understand your sentence very well.

What you mean is rank 30 years(from which year to which year) and take the 3rd place and 28th place to combine?