Solar Radiation in Acusolve

avb

I am trying to model a car which is in Sun

I have 2 questions

1) How to define the direction of solar heat flux when inputting it from AcuSflux (For eg if the sun is in North East Direction how would I incorporate that in my model.

2.) In Solar Radiation Surfaces, what does Default, Inward, Outward and Both Side represents. Is it based on whether surface receives direct solar radiation or not.

acupro

This is part of the output of     acuSflux -h

acuSflux: -ndir <str> North direction in model coordinates
acuSflux: north_direction= 1,0,0 [default]
acuSflux: -udir <str> Up direction in model coordinates
acuSflux: up_direction= 0,0,1 [default]

This is how you specify which direction is north and which is up - in your model. In this case -ndir 1,0,0 means in the model north is +X, and -udir 0,0,1 means up is +Z in the model.

This is the Help page for Solar_Radiation_Surface:
https://2022.help.altair.com/2022.1/hwcfdsolvers/acusolve/topics/acusolve/solar_radiation_surface_acusolve_com_ref.htm

From that page:

side (enumerated) [=default]    Side of the surface that receives solar heat flux.

default  -  Side is based on the element medium.

inward  -  Side facing into the element.

outward  -  Side facing away from the element.

both  -  Both sides.

 

and

 

The side parameter specifies which side of the surface is active. If the solar radiation comes from the opposite side then the surface does not interact with this radiation, that is, the surface is completely transparent. An inward side faces towards the interior of its parent element, and an outward side faces away from the element. A value of both means that both the inward and outward sides are active. A default side is chosen based on the medium parameter of the ELEMENT_SET command. For a fluid medium, default is the same as inward, and for solid and shell media, default is the same as outward.