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Chemical propulsion is still widely present within the space industry especially when it comes to exploration or earth observation missions. Despite its historical usage, some questions concerning plume induced contamination remain open. Plus, the complexity of the future missions, especially within OHB, leads to configurations where the plume is a driving key for satellite design. In fact, the thrusters could theoretically impinge all kind of optical components such as cameras, telescopes, mirrors or even radiators. However, impinging a surface does not necessarily mean possible troubles: depending on the angle, velocity and the nature of the contaminants, the performance loss can be either consequent or insignificant. Despite this hot topic, few data1, 2 or in-orbit observations3 are available. This is probably due to the complexity of a direct observation of such a phenomena. These data are very useful to calibrate the numerical modelling even if some questions are still unanswered. Meanwhile, the numerical tools progressed and computation capabilities today are far more developed than in the beginning of the investigations. Within OHB, the open source tool “openPlume” have been developed the last year based on the ray-tracing technique and by connecting the CFD calculations to the far field. This provides to the System Engineers quick, reliable and robust answers to the questions regarding the plume induced thermal fluxes or forces and torques. After the last years progress4, the extension of the tool continues to tackle contamination. This paper presents the roadmap of the “openPlumeCP contamination module” that already provides the gases distribution and implement the droplets distribution. The CFD modelling take into account each gases species after that the preliminary combustion products properties have been generated by the CEA code. The transport properties such as the viscosity and the specific heat capacities are then injected into the thruster mesh thanks to openFOAM. Once the gases distribution on the near field of the thruster is performed, the extrapolation to the far field relies on the ray-tracing algorithm. The droplets are simply injected according to an analytical formula relying on on-orbit observation. An empirical comparison with the Trinks experiments was performed and gave encouraging results for the species distribution. Thanks to this preliminary work, a first glimpse can be provided by openPlumeCP regarding the possible impact on the spacecraft surfaces. The backflow modelling remains tricky and need to be handled differently: a specific DSMC method relying on DS3V5 is used for the near field impingement. Nevertheless, the thruster lip influences the species distribution in the near field and the CFD method need to be modified. Investigations are on-going by trying to couple the CFD simulation and the DSMC part next to the lip.
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