The utilisation of the Very Low Earth Orbit (VLEO) region offers significant application specific, technological, operational, and cost benefits. However, attaining sustained and economically viable VLEO flight is challenging, primarily due to the significant, barely predictable and dynamically changing drag caused by the residual atmosphere, which leads to a rapid deterioration of any spacecraft’s orbit unless mitigated by a combination of active and passive techniques. This article addresses one passive method by optimising satellite shapes in order to achieve a minimisation of the atmospheric drag force and thus extension of operational lifetime. Contrary to previous investigations in the field, a constant internal volume is maintained to account for the placement of satellite instruments and payload inside the structure. Moreover, the satellite geometry is not varied heuristically but optimised, via a numerical 2D profile optimisation specifically developed for this purpose. From the resulting optimal satellite profiles, 3D satellite bodies are derived, which are then verified via the Direct Simulation Monte Carlo method within the open-source particle code PICLas. In addition, rather unconventional designs, i.e. ring geometries, which are based on the assumption of fully specular particle reflections, are proposed and assessed. The optimised satellite geometries offer pure passive lifetime extensions of up to $46\text{\%}$ compared to a slender reference body, while the above-mentioned ring geometries achieve passive lifetime extensions of more than $3000\text{\%}$. Finally, the article presents design recommendations for VLEO satellites in dependence of different surface properties.

超低地球轨道 (VLEO) 区域的利用提供了显着的特定应用、技术、运营和成本优势。然而，实现持续且经济上可行的 VLEO 飞行具有挑战性，这主要是由于残余大气造成的重大、难以预测和动态变化的阻力，这会导致任何航天器轨道的快速恶化，除非通过主动和被动技术的组合来缓解. 本文通过优化卫星形状来解决一种被动方法，以实现大气阻力的最小化，从而延长运行寿命。与之前在该领域的研究相反，保持恒定的内部体积以说明卫星仪器和有效载荷在结构内的放置。而且，卫星几何形状不是启发式地变化，而是通过专门为此目的开发的数字 2D 轮廓优化进行优化。从得到的最佳卫星剖面中，导出 3D 卫星主体，然后通过开源粒子代码 PICLas 中的直接模拟蒙特卡罗方法进行验证。此外，提出并评估了基于完全镜面粒子反射假设的非常规设计，即环形几何形状。优化的卫星几何形状提供高达纯无源寿命延长 然后通过开源粒子代码PICLas中的直接模拟蒙特卡罗方法进行验证。此外，提出并评估了基于完全镜面粒子反射假设的非常规设计，即环形几何形状。优化的卫星几何形状提供高达纯无源寿命延长 然后通过开源粒子代码PICLas中的直接模拟蒙特卡罗方法进行验证。此外，提出并评估了基于完全镜面粒子反射假设的非常规设计，即环形几何形状。优化的卫星几何形状提供高达纯无源寿命延长$46\text{\%}$与细长的参考体相比，上述环的几何形状实现了超过$3000\text{\%}$. 最后，本文根据不同的表面特性提出了 VLEO 卫星的设计建议。