Orbit Thermal Loads
The Orbit Thermal Loads () study step is a special case of a Time Dependent study step, where only the degrees of freedoms used for modeling the spacecraft orbit are solved for. In addition, the external irradiation is stored to be reused on multiple orbit periods in the Orbital Temperature study step or for faster post-processing of the external irradiation.
Except for the Study Settings section, see Time Dependent for all settings. This study is available with the Heat Transfer Module.
Study Settings
Select a Time unit from the list (default SI unit s) to use a time unit that is convenient for the time span of the simulation.
Then, select the Output times specification, either in terms of Orbit Period (the default) or Time steps.
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If Orbit Period is selected, output time steps will be selected based upon the dimensionless fraction of the orbital period, as specified in the Output orbit times field. Use the range operator to define a uniform spacing. For example, range(0,0.1,3) will solve for a total of three orbit periods, and output results every one-tenth of the orbit period. The orbit period is determined from the first Orbital Thermal Loads interface that is solved for.
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If Time steps is selected, specify the time interval for the output from the simulation in the Output times field using the selected time unit.
From the Tolerance list, choose Physics controlled (the default) to use the tolerance suggested by the physics. Choose User controlled to override the suggested relative tolerance with a value that you enter in the Relative tolerance field.
Additional output times will be stored immediately before and after every explicit and implicit events, for example: when the spacecraft enters and leaves the eclipse. The solver uses intermediate time stepping by default to force the time-stepping method to take at least one step in each subinterval of the specified times.