Radiation reflected between 2 buildings

[eugenetheawesome]

Hi, I was wondering if it is possible to use IES to simulate and find out the radiation reflected between 2 buildings.

Right now I've tried to simulate this problem by creating 2 buildings with an air gap (internal room) in between. The internal room consist of 100% window opening to simulate the ambient air.

However, the int surface incident solar flux actually increases when I increased the distance between the 2 buildings. Shouldn't it decrease since reflected radiation has now decreased due to the increase distance between the 2 buildings? If so how should I improve my modelling?

Can someone kindly pls assist?

[Complex Potential]

I would hazard a guess that the surface solar flux increases when you move the buildings apart because it then exposes more of the wall to direct solar gains (less self shading between the two) which is likely to have far more impact on the solar flux than the reflected components between the buildings.

If you are modelling high walls it may be beneficial to split the buildings into verticle zones, perhaps 1-2m each to give more resolution to your results because otherwise you are probably only seeing an averaged figure across the whole wall.

[eugenetheawesome]

I would hazard a guess that the surface solar flux increases when you move the buildings apart because it then exposes more of the wall to direct solar gains (less self shading between the two) which is likely to have far more impact on the solar flux than the reflected components between the buildings.

If you are modelling high walls it may be beneficial to split the buildings into verticle zones, perhaps 1-2m each to give more resolution to your results because otherwise you are probably only seeing an averaged figure across the whole wall.

Hi CP, thanks for the reply. I understand what you mean. I am trying to investigate the radiation reflected between two buildings by varying the distance and reflectivity of the walls of the building. Is there a better way that I can model this experiment to get the desired results?

[Complex Potential]

Unfortunately I don't think there is a way to distinguish between reflected energy and direct energy. Therefore what you are trying to do may not be possible using IES, although I'd be happy to be proved wrong.

[eugenetheawesome]

Hi Cp,

I have used the sectioning using divide space in edit mode. However, when I ran the simulation to investigate the radiation incident on the sectioned building, it gave me similar results for all 9 sections. I would like to find the different amount of radiation incident on individual sections of the building, is it possible to achieve this with this software? If possible should I model it or run the simulation in another way?

This is how I did the sectioning of the building.