# Solar radiation, reflection, and emission on exterior wall

I am trying to calculate solar radiation, reflection, and re-emission on exterior wall (heat transfer) with Ladybug or Honeybee:

• Please download and open the attached pdf file. For some reasons, the image changed in black color.
• I am trying to calculate 1, 2, and 3, on the specific day “from 00:00 to 24:00, 22nd August (one day).”

If I use Ladybug:

1. Can I calculate “1. Incident Radiation” with the component “Ladybug_Radiation Analysis” or “Ladybug_Surface Hourly Solar”?
2. Can I calculate “2. Reflection” with the component “Ladybug_Bounce from Surface”? How can I setup materials of wall surfaces?
3. In order to calculate “3. Re-emission” from the wall, which component can I use in Ladybug?

If I use Honeybee:
4. Which component can I use to calculate “1. Incident Radiation”?
5. Which component can I use to calculate “2. Reflection”?
6. Which component can I use to calculate “3. Re-emission”?

1. Is there any formula to calculate 2. Reflection and 3. Re-emission rate with a certain material at the location with latitude and longitude? For example, if I already know how much incident radiation is received by the sun on the brick wall surfaces in New York with the certain latitude and longitude, is there any specific percentage of 2. reflection and 3. re-emission for one day, 22nd Aug?
• My intent is to calculate “heat transfer” from the building surface to the surroundings.

Thank you so much in advance.

Diagram.pdf (21.4 KB)

@limpideyessalmon It is a simple question. You can use Radiance for three part of solar radiation in Honeybee.

Dear minggangyin,

Thanks for your response but I don’t quite understand.

What did you mean by three parts? Please explain more in detail.

Cheers!

@limpideyessalmon Three parts is from the image you posted.

Then how can I calculate “re-emission”?

Once re-emission is calculated, how do I know how far it goes? For example, which meter does the heat go to the surroundings?

Hi，@limpideyessalmon Solar radiation is composed by light and energy. You should tell us the detailed research content.If you intend do something about lighting ,you can use Radiance in Honeybee. If you intent to do something about energy, you can use Energyplus in Honeybee. So the re-emission is something about energy,you can use Energyplus in Honeybee.

My research is more about “heat transfer” from the building surface to the surrounding environment. I will take a look at the EnergyPlus in Honeybee.

By the way, do you know where can I find the “formula” to calculate “incident radiation, reflection, and re-emission”? I need to have it as reference.

Thanks again, minggangyin.

@limpideyessalmon There are a lot description about heat transfer in EnergyPlus engineer reference.
For your research, you can refer to the example created by@chris .

http://hydrashare.github.io/hydra/viewer?owner=chriswmackey&fork=hydra_2&id=Outdoor_Microclimate_Map&slide=1&scale=1&offset=0,0
And there are some useful links for you.