Ansys Learning Forum Forums Discuss Simulation Fluids Thermal Desktop Orbital Elements Reference Frame Reply To: Thermal Desktop Orbital Elements Reference Frame

Doug Bell
Ansys Employee

I was mistaken in my earlier post. The difference between our calculations is the approximation of the declination. We are using the equation (using your variable names):

decSun = orbInc*sin(L_s)

This yields the Beta angle shown on the orbit form and used in the calculations. If you need to match a precise Beta angle, you can use a basic (circular) orbit where you specify the Beta angle or you can adjust the RA Sun to get the desired Beta angle. Please note that RA Sun and Beta angles are assumed to be constant over the solution so there is a limit to how precise you can get.