Orbital Temperature
The Orbital Temperature () study step is a special case of a Time Dependent study step, where the external irradiation from a Orbit Thermal Loads study step is reused on multiple orbit periods. The external irradiation from the first orbit period is reused. This means that the external irradiation needs to be periodic over one orbit period (the physics should not include Implicit Event or Ground Pointing features). If the external irradiation is not periodic, a Time Dependent study step should be used instead where the external irradiation is recomputed for each orbit period.
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.
Use the settings under Precomputed Orbit Thermal Loads solution to specify from which Orbit Thermal Loads study step the external irradiation should be extracted.
From the Settings list, choose Reuse solution from previous step (the default) to use the external irradiation from the previous Orbit Thermal Loads study step in the study sequence, if it exists. If not, the external irradiation will be recomputed. Choose User defined to specify the Orbit Thermal Loads solution using the Study list. Select:
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None to force the external irradiation computation.
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Any other available Orbit Thermal Loads study. It can be the current solution in the sequence, or a solution from another sequence, or a solution that was stored with the Solution Store node. You select a stored solution by changing Use to the name of the stored solution. Choose a solution using the Selection list (see Values of Dependent Variables under Common Study Step Settings).
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.