Full forcig Problem with Relative Humidity

Discussions about the Version 4 concerning the core model simulations
alireza
Posts: 18
Joined: Sun Jul 07, 2019 10:09 am

Full forcig Problem with Relative Humidity

Postby alireza » Wed Feb 05, 2020 8:50 pm

Hello dear ENVI-met team
I'm using the EPW file for simulation but The Relative humidity must be added in MIN and MAX like simple forcing. When I go to the next page for putting min and max RH there is just one blank field. what should I do?
I will attach some image for more information
Best
Attachments
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Tim
Posts: 1203
Joined: Mon May 15, 2017 3:46 pm

Re: Full forcig Problem with Relative Humidity

Postby Tim » Thu Feb 06, 2020 8:59 am

Hi,

FullForcing replaces the boundary condition of SimpleForcing. The MinMax values in SimpleForcing help you to easily create a 24h cycle of data (a simple linear interpolation). If you use FullForcing and leave out one parameter, you are only able to insert an initial start value. This value can be set on the page where only the one relative humidity value is editable.

Best regards,
Tim

zhuzhuzhu
Posts: 25
Joined: Sun Dec 02, 2018 5:33 am

Re: Full forcig Problem with Relative Humidity

Postby zhuzhuzhu » Thu Feb 06, 2020 3:28 pm

Hi, Tim

I am trying to learn how to use the advanced full forcing. I tried the advanced simple forcing and full forcing with one same model. The simple one simulated well, while the full one always show "invalid floating point operation". I checked many times but failed to figure out the reason. Could you help me check why?

Best regards,
Zhuzhu
360截图20200206231630259.jpg
test.zip
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Tim
Posts: 1203
Joined: Mon May 15, 2017 3:46 pm

Re: Full forcig Problem with Relative Humidity

Postby Tim » Thu Feb 06, 2020 3:45 pm

Hi Zhuzhu,

The temperature data is corrupted. The values are in a range between 0 and 400 K ..

Best regards,
Tim

alireza
Posts: 18
Joined: Sun Jul 07, 2019 10:09 am

Re: Full forcig Problem with Relative Humidity

Postby alireza » Fri Feb 07, 2020 9:26 am

Hi TIM
I need the most realistic relative humidity as much as possible because I need this for modifying an EPW file for coupling the EnergyPlus and ENVI-met. When I'm using the epw file for Tehran downloaded from enenrgyplus.net in a 24h simulation the air temperature result is the well correspondent. (in my measurement AT reaches 48c) but the RH is high in such a dry climate. if I use the data from a meteorological station near the site and putting in simple forcing the AT to reach 40c(because the highest AT recorded in this station is 42c). I think the best option would be using the epw but putting the RH in simple forcing mode that it is not possible. is there any way that both AT and RH match well with field measurement? Where this difference comes from?
the attached image is checking the downloaded epw file by Climate Consultant that shows the peak in July is 40 but this is much more in reality and simulated results in ENVI-met.
Attachments
climate consultant.PNG

Tim
Posts: 1203
Joined: Mon May 15, 2017 3:46 pm

Re: Full forcig Problem with Relative Humidity

Postby Tim » Fri Feb 07, 2020 9:39 am

Hi,

I don't know why there is a discrepancy. However, you could create a FullForcing manually by a CSV. There, you could insert all data originating from the EPW file and replace the relative humidity values with the ones that you are sure of to be correct.
That will require some work but gives you the result that you need.

Best regards,
Tim

zhuzhuzhu
Posts: 25
Joined: Sun Dec 02, 2018 5:33 am

Re: Full forcig Problem with Relative Humidity

Postby zhuzhuzhu » Sat Feb 08, 2020 5:10 am

Hi Tim,

Thank you very much, I solve it now.

Best regards,
Zhuzhu

alireza
Posts: 18
Joined: Sun Jul 07, 2019 10:09 am

Re: Full forcig Problem with Relative Humidity

Postby alireza » Fri Feb 21, 2020 4:13 pm

Hello dear Tim
I have a situation with RH. I have changed the RH in the EPW file because the simulated RH was so high based on the EPW RH then I changed it based on a station near my site. the problem is the panic error for new RH input and i have no idea about it? should I expand the surrounding grids?
I will attach the model and EPW file(Please check the data for 25th of July in EPW file)
Most sincerely regards!
Attachments
Alireza.rar
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Tim
Posts: 1203
Joined: Mon May 15, 2017 3:46 pm

Re: Full forcig Problem with Relative Humidity

Postby Tim » Tue Feb 25, 2020 12:46 pm

Hi,

Did you check the spec. humidity values in the ForcingManager. I think that it shows a large jump during nighttime, maybe you need to correct the values slightly to be more realistic.
However, Panic Dump error most likely happens because of the wind: you do have several 180° wind direction changes during the day and additionally very high wind speeds up to 7 m/s. One of those features would be enough to cause the model to crash, in combination it is hard to make the model work. If you don't want to also modify wind speed and direction, I'd rather search for a more generic day to simulate.

Best regards,
Tim


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