Hello,
I’m trying to use Honeybee Radiance (using HB Annual Irradiance) for a study that investigates radiation on a façade. As part of this study, I’m interested in looking at the impact ground reflectance has on incident radiation.
I’m currently trying to set ground reflectance by creating a surface below my facade surface, and using an opaque modifier to set the reflectance properties for this surface. I want my modifier to be 100% diffuse reflectance, but to iterate through reflectances from 0-1, with increments of 0.1.
I’ve set specularity at 0.01, and roughness at 0.02 as I read somewhere else that if you give inputs of 0 you can get results that don’t make sense.
As an example, my modifier for 20% reflectance looks like this:
void plastic ground_context
0
0
5 0.2 0.2 0.2 0.01 0.02
For some reason, my ground reflectance modifier doesn’t have any impact on radiation on the face until I start to exceed 30% reflectance. From there, radiation on my facade surface increases pretty linearly with increasing ground reflectance until I hit 90% reflectance, and then drops off to values of radiation that I’m seeing when I’ve got reflectance set <30%. I’ve attached an image to try and show what I’m seeing.
Does anyone know why this is? Is it because ground reflectance needs to be set elsewhere? Logically these results don’t seem right, so wondering if anyone can explain what is going on?
Thank you!
