Hi All
When modelling window openings for CIBSE TM 52 and 59 thermal comfort analysis it is typically the case that windows above GF in UK will have a restricted opening of 100 mm.
And this often equates to opening angles below 10 deg. Which means that the MacroFlo opening templates cannot be used.
The alternative would be to model these as custom/sharp-edged orifices. However without knowing the equivalent orifice % opening area (as opposed to the geometric free area) this is not possible either.
The only option I can see is to model them with the smallest possible angle usable in the templates, i.e. 10 deg, and then calculate the equivalent geometric free area, and advise clients that this is the case. But this will result in an overestimation of the natural ventilation, and an underestimation of the risk of thermal discomfort.
Anyone see a way around this?
Wasted
How to model openings with 100 mm restrictions?
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Wasted Energy
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RossThompson87
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Re: How to model openings with 100 mm restrictions?
Hi,
I go down the route of using custom / sharp-edged orifices. But as you say, there is very little clear guidance on working out an equivalent area for a window. A webinar on this would be great...
Assuming you have a top hung window, I would take the equivalent area as the opening distance (i.e. 100mm) x window width.
In general flow rates through 100mm restricted windows are poor, so best to have low expectations for your results!
Ross
I go down the route of using custom / sharp-edged orifices. But as you say, there is very little clear guidance on working out an equivalent area for a window. A webinar on this would be great...
Assuming you have a top hung window, I would take the equivalent area as the opening distance (i.e. 100mm) x window width.
In general flow rates through 100mm restricted windows are poor, so best to have low expectations for your results!
Ross