High Energy Rapid Modular Ensemble of Satellites Payload Thermal Analysis Using OpenFOAM

Abstract

In a space mission design, the goal of the thermal control subsystem is to ensure that all components of the satellite stay within their operating temperature ranges. The problem becomes more critical if the mission involves nano-satellites with an astrophysics payload requiring a dedicated thermal design to keep it at low temperature, as in the case of the HERMES mission. Therefore, a thermal analysis is performed using ESATAN, one of the most used software packages among those suggested by ECSS. This gives a good overview of the temperature fields but many geometrical simplifications must be introduced in the model and all thermal interfaces must be checked. In order to asses the effect of the latter, the ESATAN results are cross-checked with those obtained using another software, OpenFOAM, in which the geometry is created directly from the CAD model of the satellite, resulting in a very accurate geometrical representation. By first comparing the view factors calculations against analytical test cases some issues emerged. These are thoroughly analyzed and discussed and it is finally shown that they do not affect the temperature field. The high level of detail of OpenFOAM highlighted interesting possible improvements in the thermal configuration of the satellite.

Spacecraft and Asteroid Thermal Image Generation for Proximity Navigation and Detection Scenarios

“…As verified in [9], such an approximation is able to catch the correct values of the view factors. Dividing by the mesh face and considering a single diffuse value for the emissivity, the equation provides the heat flux per unit area emitted by each face and intercepted by the camera:…”

“…The code offers the geometrical accuracy required to create realistic thermal images and the flexibility needed to interface with the rendering engine. For a detailed description of the code and the numerical testing, the reader can refer to [8,9]. The code has been compared to real thermal vacuum test data in a CubeSat scenario proving to be reliable in computing the temperature field; moreover, preliminary mono-material cases using such code for thermal image generation are presented in [2,10,11].…”

HERMES CubeSat Payload Thermal Balance Test and Comparison with Finite Volume Thermal Model

“…The code has been selected because it is able to deal with complex geometries and maintain the geometrical accuracy. Furthermore, the contact interfaces are directly extracted from the geometry which avoids any simplification in the contact area definition, leading to more accurate results [7]. Moreover, the contact interface setup is fully automated and the code has already been numerically tested and compared against ESATAN for such type of application [7,42].…”

“…The FVTM model is computed in Open-FOAM, a widely used open-source Computational Fluid Dynamics (CFD) solver which support also several heat transfer models. The model has a more accurate geometry with respect to the Lumped Parameter Approach method which is commonly used in space thermal analyses, e.g., when simulating with the ESATAN software, the European Space Agency Lumped Parameter Approach software used for thermal analyses; for more information on ESATAN the reader can refer to [7]. Indeed, the FVTM offers better insight into the heat fluxes within the model as shown in [7][8][9].…”

“…The model has a more accurate geometry with respect to the Lumped Parameter Approach method which is commonly used in space thermal analyses, e.g., when simulating with the ESATAN software, the European Space Agency Lumped Parameter Approach software used for thermal analyses; for more information on ESATAN the reader can refer to [7]. Indeed, the FVTM offers better insight into the heat fluxes within the model as shown in [7][8][9]. In this work, the post-processing of the experimental data is presented, and the test data is compared with the FVTM results, proving the application of the novel method to be reliable.…”