1. Solution exception:Sum of shade transmittance and reflectance (1.3) is greater than 1.
I guess ‘reflectance’ doesn’t automatically adapt … so that makes sense… so then if i set both the transmittance and reflectance values (0.8, 0.2, respectively), this HB component is now happy, but if I try and run a simulation, now instead E+ complains:
** Severe ** WindowMaterial:Shade="SHADEMATERIAL_00C7B709", Illegal value combination.
** ~~~ ** Solar Transmittance + Solar Reflectance not < 1.0
Curious: Am I using this component wrong? I can make it work by setting transmittance to 0.799999, but I feel like this component should be smarter than that? Doesn’t t + r always == 1?
The conservation of incident radiation (energy) tells that the sum of the main three components of a radiated beam to a substance should be equal to 1:
1- transmittance
2- reflectance
3- absorbed
The question is are you trying to simulate a very special kind of material that is in the experimental lab scale, some kind of special window?
Since if the T+R == 1, it means that the Absorbed == 0.00, this means that this specific material does not retain any energy as heat or internal energy or the material is highly highly transmitted or highly highly reflected (polymers with dyes, or …)
In this specific system, you need to use other physical equations, I am not sure E+ has this specific thing, you need to change the core calculation of the E+.
Interesting… so in E+, if I input 0.8 for transmittance, then the reflectance is not automatically 0.2?
I definitely was not trying to model anything special or abnormal - I was mostly suggesting that I thought the HB shade component could do more to help ensure that the user didn’t get errors later on - but perhaps there is some nuance I am missing that means auto-calcuation is not possible?
only for opaque materials, since there is no transmittance (like walls, you cannot see the sun light from the other side of wall), the absorptance = 1-reflectance
