Different results with the same input parameters for a HoneyBee simulation

[angeline_christine]

Hello,

I’m an intern and I’m working on grasshopper and Honeybee. I have to simulate different variables on an architectural project.
I would like to calculate the daylight autonomy of a room and since some simulations, I noticed that my outputs are different while my inputs are the same.
Would it be possible to have an answer to this and what is the solution to have each time the right results.

Thank you in advance for your help.

[mikkel]

Hi @angeline_christine,

How much of a difference do you get? With Radiance some difference is expected. See this:

Different results on different computers

Radiance uses a stochastic sampling for calculation and 5-10% difference is expected. If you want to minimize the difference you can set radPar to be high. Also check this post on Radiance discussion group: http://comments.gmane.org/gmane.comp.graphics.radiance.general/2685 Mostapha

Try to increase the Radiance parameters and see if the difference between two simulations gets smaller.

[angeline_christine]

Thank you for your quick response.
In the radiance settings, what does “recipe type” mean, when I change it, my results changes a lot. Please ?

[angeline_christine]

My results are different by a few points with each simulation but I don’t know which version to rely on as I am waiting for accurate results to use afterwards.

[mikkel]

For an annual simulation you should input 2 in _recipe_type. Change the _detail_level_ if needed.

[angeline_christine]

Okay perfect, i will do this !
Thank you very much !

[kanshan]

dear mikkel,

i’m sorry to bother you, but i also want to know what’s the differences between the three recipes, there are any references to explain the three recipes? in addition, if i want to simulate the annual solar irradiance on building facades, which recipe would you recommend?