Search found 416 matches

by Thomas
Mon Feb 26, 2024 3:46 am -1100
Forum: Hygrothermal Sources & Sinks
Topic: Moisture source not considered
Replies: 6
Views: 1577

Re: Moisture source not considered

Hi Benoît, the details of the air infiltration source are as follows: For each time step, WUFI determines the lowest temperature occurring in the region covered by the source. If this temperature is higher than the dew point temperature of the indoor air, nothing happens. If it is lower, condensatio...
by Thomas
Fri Feb 23, 2024 3:28 am -1100
Forum: Hygrothermal Sources & Sinks
Topic: Moisture source not considered
Replies: 6
Views: 1577

Re: Moisture source not considered

Hi Benoît,

I will check with the programmers about how the air infiltration source function has been implemented exactly, regarding the temperature evaluation and the moisture release within the source region.

Kind regards,
Thomas
by Thomas
Wed Feb 21, 2024 5:30 am -1100
Forum: Hygrothermal Sources & Sinks
Topic: Moisture source not considered
Replies: 6
Views: 1577

Re: Moisture source not considered

Hi Benoît, maybe it is too warm at the location of the source? An air infiltration source does not automatically release a certain amount of moisture, it only releases moisture if the temperature at the location of the source is below the dew point temperature of the indoor air. (The model assumes t...
by Thomas
Tue Feb 20, 2024 5:36 am -1100
Forum: Hygrothermal Sources & Sinks
Topic: Moisture source not considered
Replies: 6
Views: 1577

Re: Moisture source not considered

Hi Benoît,

did you make sure that either the stack height or the overpressure parameter of the air infiltration model is non-zero? If both are zero, the moisture source will be zero, too.

Kind regards,
Thomas
by Thomas
Mon Nov 20, 2023 2:38 am -1100
Forum: Climate
Topic: wind speed
Replies: 1
Views: 3694

Re: wind speed

Hi bamboo, the WAC file contains the average hourly radiation intensity in Watt/m². If the average radiation intensity is 1 Watt per square meter, this is the same as 1 Joule per second and per square meter. The total energy input after one hour (3600 seconds) is 3600 Joule per hour and per square m...
by Thomas
Mon Nov 20, 2023 2:06 am -1100
Forum: Climate
Topic: rain can not read
Replies: 2
Views: 2467

Re: rain can not read

Hello bamboo, WUFI does read rainfall in a KLI file. If in your case it does not, you may have some error in the file format. However, if you wish to use rain data or solar radiation data for your simulation, there is another reason why you should prefer the WAC format: Rain and radiation are direct...
by Thomas
Mon Oct 30, 2023 2:58 am -1100
Forum: Material
Topic: aluminium?
Replies: 1
Views: 2134

Re: aluminium?

Hi bamboo, if your aluminum sheet is at the surface of the building component, its only hygrothermal function will be to prevent the absorption of rain water and the exchange of vapour with the outside air. Due to its small thickness and high thermal conductivity, its effect on the thermal condition...
by Thomas
Wed Oct 25, 2023 10:22 pm -1100
Forum: Climate
Topic: Create a short-term climate document
Replies: 2
Views: 2305

Re: Create a short-term climate document

Hi bamboo, WAC files can have any length, so I would recommend to use the WAC format for your short-term climate file. WAC files with only one single hourly data line are possible, and WAC files with 30 years or more are possible, too. The tool for creating climate files has two years pre-defined, b...
by Thomas
Wed Sep 06, 2023 10:02 pm -1100
Forum: WUFI 2D
Topic: Moisture accumulation
Replies: 1
Views: 3600

Re: Moisture accumulation

Hi Agnes, this may not be a question of moisture transport but of the moisture sorption equilibrium in a temperature gradient. The insulation material you are using is probably vapour -permeable but has no (or only little) liquid transport capability. Under these circumstances, vapour diffusion is t...
by Thomas
Fri Aug 18, 2023 2:08 am -1100
Forum: WUFI 2D
Topic: solar azimuth has no influence on temperatures
Replies: 2
Views: 2281

Re: solar azimuth has no influence on temperatures

Hi Willem, unfortunately, you have encountered a bug in WUFI-2D. Apparently the problem is caused by WUFI-2D failing to update the file with the boundary conditions. For performance reasons, WUFI-2D creates a file *.bcli ("binary climate") which contains the pre-processed boundary conditio...
by Thomas
Tue Jul 18, 2023 2:16 am -1100
Forum: WUFI 2D
Topic: Simulation eines Photovoltaikpanels
Replies: 3
Views: 2663

Re: Simulation eines Photovoltaikpanels

Gibt es eine Mindestschichtdicke damit das Programm die Schichten erkennt und mit diesen die Berechnung durchführen kann? Hallo Milan, eine formelle Mindestdicke gibt es nicht. Je nach Problemstellung und numerischen Eigenschaften des konkreten Falles sind allerdings unterhalb einer gewissen Mindes...
by Thomas
Fri Jun 16, 2023 1:14 am -1100
Forum: WUFI 2D
Topic: Widersprüchliche Simulationsergebnisse
Replies: 4
Views: 3063

Re: Widersprüchliche Simulationsergebnisse

Hallo Christian.P, Ihr Diagramm stellt einen 24stündigen Zeitraum dar, mit einer Nacht am Anfang, dem Tag in der Mitte und wieder einer Nacht am Ende. Das merkwürdige Temperaturverhalten tritt während der ersten Nacht auf, aber nicht während des Tages und auch nicht während der zweiten Nacht. Möglic...
by Thomas
Tue May 09, 2023 6:40 am -1100
Forum: Material
Topic: Ableitungs der Feuchtespeicherfunktion aus Sättigungskoeffzient
Replies: 3
Views: 5411

Re: Ableitungs der Feuchtespeicherfunktion aus Sättigungskoeffzient

Hallo PScharfA, vielen Dank für den übersandten Laborbericht. Anhand der Datentabelle lässt sich ersehen, dass der "Sättigungskoeffizient" die als Porenfüllgrad ausgedrückte freie Sättigung ist. Eine Umrechnung des Sättigungskoeffizienten in die freie Sättigung erübrigt sich aber, weil die...
by Thomas
Mon Apr 17, 2023 3:46 am -1100
Forum: WUFI Pro
Topic: Material parameters in the database
Replies: 2
Views: 2310

Re: Material parameters in the database

Hi K-A-R-E-L, the maximum value of the thermal conductivity for the glass wool is indeed the thermal conductivity of water, for exactly the reason you state. There are two ways in WUFI to enter a moisture-dependent thermal conductivity: entering a detailed tabulation of the conductivities, or enteri...
by Thomas
Sun Mar 26, 2023 10:32 pm -1100
Forum: Material
Topic: Shell Limestone (Muschelkalk) as a cladding
Replies: 1
Views: 4942

Re: Shell Limestone (Muschelkalk) as a cladding

Hi PScharfA, I consulted the original data sheet from which the Shell Limestone data for the material database were taken, and it has no liquid transport coefficients either. (So these coefficients have not been lost at some point - they never existed.) The reason may be explained by the note "...