Search found 114 matches

by helge
Wed Jun 24, 2020 8:58 am
Forum: LEONARDO 4
Topic: Model Comparison
Replies: 9
Views: 70

Re: Model Comparison

Dear Ilaria, Thank you very much to bring that to our attention. Could you please upload screenshots of absolute PET for 16:00h with and without the greening? Also it would help if you could upload (to wetransfer) the model results of biomet for 16:00 (edt and edx file) for the simulations with and ...
by helge
Mon Jun 22, 2020 2:28 pm
Forum: Beginner's Corner
Topic: Negative Surface Temperature
Replies: 4
Views: 27

Re: Negative Surface Temperature

Dear Gerhard,

That indeed looks strange. Are you using the current version of ENVI-met (4.4.5)? If so, could you upload the INX and SIMX as zip-file?

Best
Helge
by helge
Tue May 26, 2020 1:28 pm
Forum: ENVI-met 4 (Main Simulation Model)
Topic: Building air volume
Replies: 4
Views: 60

Re: Building air volume

Dear a346,

in equation 14 in your last post, you can see c_p, this is the specific heat capacity of air [J * (kg *K)^-1]

Best
Helge
by helge
Fri May 08, 2020 7:37 am
Forum: ENVI-met 4 (Main Simulation Model)
Topic: Building air volume
Replies: 4
Views: 60

Re: Building air volume

Dear a346, yes, both specific heat capacity of air and air volume are taken into account. Sensible heat transfer between the inner building wall and the air is calculated using a constant heat convection coefficient (7.7 [W/(m2 K)] in accordance to DIN 6946). Yes, you can either set the indoor air t...
by helge
Wed Apr 29, 2020 2:35 pm
Forum: LEONARDO 4
Topic: Vapor flux and plant CO2 flux units
Replies: 4
Views: 44

Re: Vapor flux and plant CO2 flux units

Dear Adrien, the unit of the vapor flux is correct, however you can recalculate it to a flux per area and second by simply multiplying the value with the density of air (around 1.29 [kg/m3]). The easiest way to do so in LEONARDO would be to use the "Calculate between Layers" option in the ...
by helge
Wed Apr 29, 2020 11:38 am
Forum: LEONARDO 4
Topic: Vapor flux and plant CO2 flux units
Replies: 4
Views: 44

Re: Vapor flux and plant CO2 flux units

Dear Adrien, We are sorry, there was indeed a mix-up in the unit for CO2 flux in the vegetation output. Apparently we only corrected it in the atmosphere outputs. There the unit is correctly given as "Plant CO2 Flux (mg/(m²s))" Internally we use mg(CO2) / (kg(Air)*s) - by multiplying with ...
by helge
Tue Mar 31, 2020 3:14 pm
Forum: ENVI-met 4 (Main Simulation Model)
Topic: Singwalls and reflected shortwave radiation(IVS on)
Replies: 9
Views: 149

Re: Singwalls and reflected shortwave radiation(IVS on)

Dear Jack, yes, currently we do not differentiate between the two "sides" of single walls in our outputs. The reason you see higher values for reflected SW radiation beneath the single wall is that the sum or reflected sw radiation from the lower hemisphere (mainly ground) is higher than f...
by helge
Thu Feb 06, 2020 10:31 am
Forum: ENVI-met 4 (Main Simulation Model)
Topic: Questions about radiation results
Replies: 13
Views: 166

Re: Questions about radiation results

Dear Benjamin,

what exactly are your boundary conditions? Are you using full forcing? Some of our radiation outputs are relative to a normal surface (always perpendicular to the incoming direct shortwave radiation).

Best
Helge
by helge
Tue Jan 21, 2020 10:12 am
Forum: ENVI-met 4 (Main Simulation Model)
Topic: Formula of PPD
Replies: 8
Views: 122

Re: Formula of PPD

Dear ENVI-met, Thank you both for your answers. Is the calculation result of wind speed in the four indexes of wind speed, temperature, radiation, and PMV more reliable when the temperature is below zero? Best wishes, Pat Dear Pat, in general all newer indices (PET, UTCI) will result in much more r...
by helge
Thu Jan 09, 2020 10:54 am
Forum: ENVI-met 4 (Main Simulation Model)
Topic: Spray water
Replies: 44
Views: 1081

Re: Spray water

Dear all,

Thank you very much for your input - this is very helpful for us!
We are have been looking into this issue and ran some test simulations.
Attached you will find an updated preliminary version (the input is in g/s). We are happy to receive feedback from you

Best
Helge
by helge
Mon Dec 09, 2019 10:39 am
Forum: ENVI-met 4 (Main Simulation Model)
Topic: u-value and internal temp. of walls
Replies: 11
Views: 182

Re: u-value and internal temp. of walls

Dear Aaya,

the two walls are hard to compare. Their thickness is very different... How long did your simulation run? Is the building and the building volume inside identical?
We would need some more information.

Best
Helge
by helge
Fri Sep 20, 2019 9:24 am
Forum: Albero
Topic: LAD and percentage of solar radiation transmission
Replies: 1
Views: 127

Re: LAD and percentage of solar radiation transmission

Hi Stella,

the transmittance of direct radiation is calculated using raytracing and a extinction coefficient:

extinctionCoeff = e^(-0.5 * (1-transmittance of leaves) * LAD[x,y,z] * (length of ray))

Best
Helge
by helge
Sat Sep 14, 2019 7:07 am
Forum: LEONARDO 4
Topic: Does Leonardo have the ability to display illuminance?
Replies: 1
Views: 136

Re: Does Leonardo have the ability to display illuminance?

Dear AARRII,

no lux is not simulated sorry

Best
Helge
by helge
Tue Aug 13, 2019 1:40 pm
Forum: ENVI-met 4 (Main Simulation Model)
Topic: Questions on simulations using the full forcing possibility
Replies: 19
Views: 409

Re: Questions on simulations using the full forcing possibility

Dear A-),

Thank you for the feedback we will have a look into it by simulating a small test area and will get back to you.

Best Helge
by helge
Mon Aug 12, 2019 10:57 am
Forum: ENVI-met 4 (Main Simulation Model)
Topic: Questions on simulations using the full forcing possibility
Replies: 19
Views: 409

Re: Questions on simulations using the full forcing possibility

Dear A-) We had a look at your FOX-Files: the 20:00:00 and 20:30:00 values from 02th August were missing. We strongly believe your values are in the "lambert" format. The radiation data is not relative to a horizontal surface but rather to a surface that is always perpendicular to the sun....

Go to advanced search