Development of high-precision thermal models for the simulation of thermally induced perturbation effects

精确的热模拟对于高精度的基础物理和大地测量任务变得越来越重要，其中精确了解热对扰动预算的贡献对于使命的成功至关重要。我们提出了一个先进的工具，精确的热建模和精确的热力/扭矩计算，可应用于卫星任务或地面实验的扰动知识的高要求的发展。由于采用了基于表面的计算方法，还将有可能计算太阳辐射压力或空间碎片撞击等其他影响所产生的扰动。作为该方法的一个应用，将使用该方法和一个已经飞行的深空使命的完整的一套真实的飞行遥测数据计算先锋10/11探测器对扰动预算的热贡献。这将导致更好地理解的热效应和澄清的异常加速度的量，可以解释的热辐射。同样，所提出的方法将被应用于其他当前的高精度基础物理任务，如丽莎探路者，丽莎和显微镜，其中精确的扰动建模是至关重要的使命的成功。大地测量任务也将受益于这种分析。对于丽莎和Pioneer，将开发一个复杂的有限元模型，并进行详细的热分析，以改善当前热模型的不确定性[1，2]。ZARM热评估软件（TES）针对不同使命概念的准确性、处理和适应性将相对于当前热建模工具得到极大改善。此外，我们的方法是第一个使用高度详细的有限元模型的航天器几何形状的直接光线跟踪方法来计算所产生的力和扭矩，由于热辐射。除了用于空间实验的热建模外，该方法还将适用于地球上的高精度实验，例如使用光学谐振器的迈克尔逊-莫雷实验（详见[3，4]）。此外，机载传感器上的热致干扰力将是可计算的，因为每个模型表面上的每个力分数在仿真过程中确定。

Exact thermal modeling becomes increasingly important for high precision fundamental physics and geodesy missions where an exact knowledge of the thermal contributions to the disturbance budget is crucial for the mission success. We propose the development of a sophisticated tool for exact thermal modeling and exact thermal force/torque computation which can be applied to satellite missions or ground based experiments with high requirements on perturbation knowledge. Due to a surface-based computation approach it will also be possible to compute the disturbances originating from other influences like solar radiation pressure or space debris impact. As an application for the method, the thermal contribution of the Pioneer 10/11 probe to the disturbance budget will be computed thus using the method with a complete set of real flight telemetry data for an already flown deep space mission. This will lead to a better understanding of the thermal effects and clarifies the amount of anomalous acceleration that can be explained by thermal radiation.Likewise, the proposed method will be applied for other current high precision fundamental physics missions like LISA pathfinder, LISA and MICROSCOPE where an exact disturbance modeling is crucial for the mission success. Also geodesy missions will benefit from such an analysis. For LISA and Pioneer a sophisticated FE model will be developed and detailed thermal analysis will be conducted to improve the uncertainties in current thermal models [1, 2].The accuracy, handling and adaption of the ZARM Thermal Evaluation software (TES) for different mission concepts will be highly improved with respect to current tools for thermal modeling. Furthermore our approach is the first one that uses highly detailed FE models of the spacecraft geometries in a direct raytracing approach to compute the resulting forces and torques due to thermal radiation. As well as for the thermal modeling of spacebound experiments the method will be applicable to high precision experiments on Earth such as the Michelson-Morley experiment with optical resonators (see [3, 4] for details). Also the thermally induced disturbance forces on onboard sensors will be computable because each force fraction on each model surface is determined in the simulation process.