Acta Astronautica最新文献_第8页

Decay time estimate for LEO spacecraft 低地轨道航天器的衰减时间估计

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-24 DOI: 10.1016/j.actaastro.2024.09.045

The growing concerns posed by orbital debris represent a serious threat to the future of space operations in low Earth orbit. With the goal of limiting the formation of new debris, space agencies are proposing international guidelines that satellites should be able to deorbiting within 25 years of the end of their operational life. Orbital decay is typically caused by atmospheric drag, so estimating the decay time of a satellite subject to drag is critical to assessing whether the guidelines are met. However, such estimate is a very challenging task because of the difficulty of accurately modeling atmospheric properties and because of the coupling of orbital dynamics with spacecraft attitude. In this paper, a simplified algorithm based on the King-Hele formulation is proposed to rapidly estimate the decay time of an orbiting satellite without imposing any assumptions on the spacecraft’s nominal size, mass, geometry or attitude. The algorithm accounts for the effect of solar activity level variations on atmospheric properties and drag coefficient through an iterative procedure and can be applied to any object in orbit. Numerical tests show that the predictions in terms of decay times are very accurate for satellites that are quite different in size and geometry, including the presence of an aerodynamic drag augmentation system such as a drag sail.

轨道碎片带来的问题日益严重，对低地球轨道空间业务的未来构成严重威胁。为了限制新碎片的形成，航天机构正在提出国际准则，规定卫星应能在其运行寿命结束后 25 年内脱离轨道。轨道衰减通常是由大气阻力造成的，因此估算受阻力影响的卫星的衰减时间对于评估是否符合指导方针至关重要。然而，由于难以对大气特性进行精确建模，以及轨道动力学与航天器姿态的耦合，这种估算是一项非常具有挑战性的任务。本文提出了一种基于 King-Hele 公式的简化算法，用于快速估算轨道卫星的衰减时间，而无需对航天器的标称尺寸、质量、几何形状或姿态做出任何假设。该算法通过迭代程序考虑了太阳活动水平变化对大气特性和阻力系数的影响，可应用于任何在轨物体。数值测试表明，对于大小和几何形状迥异的卫星，包括存在空气阻力增强系统（如阻力帆）的情况，衰减时间的预测非常准确。

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引用次数: 0

Spacecraft protection against man-made and natural space debris particles 保护航天器免受人造和自然空间碎片颗粒的伤害

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-24 DOI: 10.1016/j.actaastro.2024.09.053

Classification of space objects according to their size, mass and density is presented. Methods developed for assessing the degree of near-Earth space contamination by space debris are reviewed briefly. General principles of providing passive and active protection for spacecraft are analyzed. Based on the developed model of particle motion under the conditions of electrodynamic armor, the areas of its efficient application are specified. It is shown that the current level of development of structural materials and high-pulse energy storage devices does not fully ensure the possibility of their full-scale efficient use in spacecraft protection systems. It is stated that it is necessary to develop additional measures to ensure the space flight safety, for example, by developing service spacecraft on the basis of unified space platforms, the primary purpose of which would be the active removal of space debris.

介绍了根据空间物体的大小、质量和密度对其进行的分类。简要回顾了为评估空间碎片对近地空间的污染程度而开发的方法。分析了为航天器提供被动和主动保护的一般原则。根据所开发的粒子在电动装甲条件下的运动模型，具体说明了其有效应用的领域。研究表明，结构材料和高脉冲储能装置目前的发展水平并不能完全确保在航天器保护系统中全面有效地使用它们。报告指出，有必要制定其他措施来确保空间飞行安全，例如，在统一空间平台的基础上开发服务航天器，其主要目的是主动清除空间碎片。

引用次数: 0

Analysis of unstable combustion caused by the Gas–Liquid two-phase flow in small hypergolic propellant engines 小型双酚推进剂发动机气液两相流引起的不稳定燃烧分析

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-23 DOI: 10.1016/j.actaastro.2024.09.033

Hypergolic bipropellant engines are extensively used in spacecraft operations. In these engines, the combustion reaction is initiated by the impinging jets of the oxidizer and fuel in the liquid phase. The most commonly used hypergolic fuels, hydrazine and monomethylhydrazine, as well as the oxidizer, nitrogen tetroxide, are all in liquid state under room temperature and atmospheric pressure conditions. However, as these engines are operated in a space vacuum, a portion of the propellant inevitably evaporates because of low-pressure boiling immediately after engine start-up. The mixing of gas with liquid propellant results in unstable combustion, and minimizing this effect is critical for the engine design. Particularly, preventing high-frequency combustion instability is essential as it can be detrimental to the engine. This paper presents a mechanism that activates high-frequency combustion instability, realized by analyzing the pressure within the combustion chamber during artificially induced unstable combustion. Furthermore, the methodology for establishing operational constraints based on the proposed mechanism is clarified, along with the method for collecting test data. The study findings provide important indicators for the design criteria of bipropellant engines, contributing to the diversification and complexity of space development programs.

超醇双推进剂发动机广泛用于航天器运行。在这些发动机中，燃烧反应是由液相氧化剂和燃料的撞击喷流引发的。在室温和大气压力条件下，最常用的双质燃料肼和一甲基肼以及氧化剂四氧化二氮均为液态。然而，由于这些发动机是在太空真空中运行的，因此在发动机启动后会立即发生低压沸腾，从而不可避免地蒸发掉一部分推进剂。气体与液态推进剂的混合会导致燃烧不稳定，因此尽量减少这种影响对发动机的设计至关重要。特别是，防止高频燃烧不稳定至关重要，因为它会对发动机造成损害。本文通过分析人工诱导不稳定燃烧时燃烧室内的压力，提出了一种激活高频燃烧不稳定性的机制。此外，还阐明了根据所提出的机制建立运行限制的方法，以及收集测试数据的方法。研究结果为双推进剂发动机的设计标准提供了重要指标，有助于空间开发项目的多样化和复杂化。

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引用次数: 0

Drag sail attitude tracking via nonlinear control 通过非线性控制进行拖曳帆姿态跟踪

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-23 DOI: 10.1016/j.actaastro.2024.09.046

A drag sail is a propellantless device suitable for passive deorbiting of satellites after their end-of-life. It exploits atmospheric drag to gradually reduce the kinetic energy of the decommissioned satellite and cause it to lose altitude over time. It is well known that the braking effect of the atmosphere is greater the surface exposed to the flow of the atmospheric particles relative to the satellite. For this reason, a drag sail is essentially a large and lightweight membrane, which is deployed by the satellite when it is to begin orbital decay. For given environmental/initial conditions and inertial characteristics of the deployed system, the braking effect of a drag sail is more intense if its perpendicular axis is constantly aligned with the direction of the relative particle flow. For this purpose, a sliding mode control strategy is adopted. The reference to follow is obtained by propagating the spacecraft orbital dynamics along with its attitude dynamics. Various orbital perturbations and the disturbance torque due to atmospheric drag are implemented in the numerical code to verify the robustness of the proposed control law. It is also assumed that the spacecraft control torque vector is bounded in magnitude and always belongs to the plane of the braking device. The results show that the proposed strategy is effective in accurately tracking the reference attitude and that it is robust, being able to track a reference that varies unpredictably due to both orbital and attitude perturbations.

阻力帆是一种无推进器装置，适用于卫星报废后的被动离轨。它利用大气阻力逐渐减少退役卫星的动能，使其随着时间的推移逐渐降低高度。众所周知，相对于卫星而言，暴露在大气粒子流中的表面越大，大气的制动效应就越大。因此，阻力帆实质上是一个大而轻的薄膜，卫星在开始轨道衰减时将其展开。在给定的环境/初始条件和部署系统的惯性特性下，如果阻力帆的垂直轴始终与相对粒子流的方向保持一致，则阻力帆的制动效果会更强。为此，采用了滑动模式控制策略。通过传播航天器的轨道动力学及其姿态动力学，可获得后续参考。在数值代码中实现了各种轨道扰动和大气阻力造成的干扰力矩，以验证所提议的控制法则的鲁棒性。此外，还假设航天器控制扭矩矢量的大小是有界的，并且始终属于制动装置的平面。结果表明，所提出的策略在准确跟踪参考姿态方面是有效的，而且具有鲁棒性，能够跟踪因轨道和姿态扰动而不可预测变化的参考姿态。

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引用次数: 0

Monitoring JUICE deployment operations with high-accuracy accelerometer data 利用高精度加速度计数据监测 JUICE 部署运行情况

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-23 DOI: 10.1016/j.actaastro.2024.09.047

The Jupiter Icy Moons Explorer (JUICE) mission is a cornerstone of ESA's Cosmic Vision 2015–2025 program devoted to the scientific exploration of Jupiter and its icy moons. Launched on April 14, 2023, from French Guiana, JUICE will perform multiple gravity assists, including an unprecedented lunar-Earth double gravity assist, in order to shape its trajectory to Jupiter, where it will arrive in July 2031. Thanks to a suite of 10 scientific instruments, JUICE will carry out a comprehensive investigation of the jovian system, with special focus on Ganymede. Among these experiments is the Gravity and Geophysics of Jupiter and the Galilean Moons (3GM) radio science and planetary geodesy experiment, supported by the onboard High Accuracy Accelerometer (HAA). The HAA, a three-axis spring mass accelerometer, measures the non-gravitational perturbations acting on the spacecraft, that need to be measured in order to fully exploit the highly accurate range and range rate measurements of 3GM. This paper analyzes the HAA data collected in the very early phase of the mission, to monitor the initial deployment of the spacecraft's moving appendages. The vibration modes of the magnetometer boom and solar arrays were clearly detected during the appendages' deployment, as well as the latching of the Langmuir probe hinges. The detected resonance frequencies of the first and second magnetometer boom bending modes are equal to 0.44 and 0.46 Hz, respectively. The HAA data contributed to identifying the root-cause of the anomalous Radar for Icy Moon Exploration (RIME) antenna deployment. The strong external perturbations due to the actuators' activation have been used to characterize the spacecraft tranquillization time. Despite the significant increase in the spacecraft noise floor during deployment events, the full sensitivity of the instrument was regained within 10 min. This information can be used to plan the spacecraft operations during the scientific phase of the mission.

木星冰月探测器（JUICE）任务是欧空局2015-2025年宇宙愿景计划的基石，该计划致力于对木星及其冰月进行科学探索。JUICE于2023年4月14日从法属圭亚那发射升空，它将执行多重重力辅助，包括前所未有的月地双重重力辅助，以确定其飞往木星的轨道，并于2031年7月抵达木星。借助 10 套科学仪器，JUICE 将对木星系统进行全面调查，重点是木卫三。这些实验包括木星和伽利略卫星的重力和地球物理学（3GM）无线电科学和行星大地测量实验，由星载高精度加速计（HAA）提供支持。HAA 是一个三轴弹簧质量加速度计，用于测量作用在航天器上的非重力扰动，为了充分利用 3GM 的高精度测距和测距速率测量，需要对这些扰动进行测量。本文分析了在任务早期阶段收集的 HAA 数据，以监测航天器移动附属装置的初始部署。在附属装置的部署过程中，磁强计吊杆和太阳能电池阵列的振动模式以及朗缪尔探针铰链的锁定都被清晰地探测到。检测到的第一和第二磁强计吊杆弯曲模式的共振频率分别为 0.44 和 0.46 赫兹。HAA 数据有助于确定冰月探测雷达（RIME）天线部署异常的根本原因。致动器启动时产生的强烈外部扰动被用来描述航天器静止时间的特征。尽管在部署过程中航天器本底噪声明显增加，但仪器在 10 分钟内就恢复了全部灵敏度。这一信息可用于规划飞行任务科学阶段的航天器操作。

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引用次数: 0

Modeling and control of perturbation torques and mass distribution impact on a tethered system for a 12U CubeSat in sun-synchronous orbit 模拟和控制扰动扭矩和质量分布对太阳同步轨道上 12U 立方体卫星系留系统的影响

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-23 DOI: 10.1016/j.actaastro.2024.09.043

Tethered CubeSat systems are characterized by momentum exchange and gravity gradient stabilization, and encounter stability challenges, especially with shorter tethers in highly inclined and eccentric orbits. This study investigates the libration dynamics of a 12U CubeSat in its stowed configuration, which separates into two satellites connected via tether, throughout its deployment, station-keeping, and retrieval phases. Two deployed configurations, symmetrical 6U-6U, and asymmetrical 8U-4U connected by a non-conductive tether with a maximum length of 100 m are analyzed. The study accounts for perturbations including Earth’s oblateness, atmospheric drag, solar radiation pressure, and lunisolar gravitation, modeling the tether as a rigid, extendable rod and the satellites as lumped masses. The translational and rotational dynamics are decoupled, assuming the system’s center of mass follows an unperturbed Keplerian Sun-synchronous orbit at altitudes between 400 and 600 km. A tension control strategy based on Lyapunov’s direct method and supplemented by external actuation torques is explored. Results show high orbit eccentricity significantly affects the maximum in-plane libration angle. The 6U-6U system experiences smaller disturbance torques but greater tether tension variations than the 8U-4U system. Both configurations exhibit larger in-plane oscillations compared to near-zero out-of-plane oscillations, nonetheless, eclipse passages exacerbate the out-of-plane libration of the 8U-4U system. Relative stability is maintained during deployment, however, retrieval is chaotic, with notable oscillations in libration angles and tether tension. The tension control strategy effectively dampens oscillations during retrieval but loses effectiveness as tether tension approaches zero at retrieval’s conclusion. External actuation torques, ranging from 1-2 mN m for deployment to 15 mN m for retrieval, complement tension control.

系留立方体卫星系统的特点是动量交换和重力梯度稳定，并遇到稳定性挑战，特别是在高倾斜和偏心轨道上使用较短系留时。本研究调查了一颗12U立方体卫星在整个部署、驻留和回收阶段的收放配置（通过系绳连接分成两颗卫星）中的振动动力学。对对称的 6U-6U 和不对称的 8U-4U 两种部署配置进行了分析，这两种配置通过最大长度为 100 米的非导电系绳连接。研究考虑了包括地球扁平化、大气阻力、太阳辐射压力和太阳引力在内的扰动因素，将系绳建模为一根刚性可伸展的杆，卫星建模为整块质量。平移和旋转动力学是解耦的，假定系统的质心在 400 至 600 千米的高度上沿着不受干扰的开普勒太阳同步轨道运行。研究探讨了基于李亚普诺夫直接法并辅以外部致动力矩的张力控制策略。结果表明，高轨道偏心率对最大平面内跃迁角有很大影响。与 8U-4U 系统相比，6U-6U 系统受到的干扰力矩较小，但系绳张力变化较大。与接近零的平面外振荡相比，两种配置都表现出更大的平面内振荡，然而，日食通道加剧了 8U-4U 系统的平面外振荡。系统在部署过程中保持了相对稳定，但在回收过程中却出现了混乱，平衡角和系绳张力出现了明显的振荡。张力控制策略有效地抑制了回收过程中的振荡，但当回收结束时系绳张力趋近于零时，张力控制策略就失去了作用。外部促动扭矩（部署时为 1-2 mN m，回收时为 15 mN m）是对张力控制的补充。

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引用次数: 0

Design and dynamics of a deployable assembly module via rollable booms 通过可滚动吊杆实现可部署装配模块的设计和动力学特性

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-22 DOI: 10.1016/j.actaastro.2024.09.049

On-orbit assembly via deployable modules is a promising way to build large space structures. In this paper, a deployable assembly module is designed for large space structures in both mechanical and electronic aspects in detail. The assembly module utilizes motor-driven rollable booms to achieve high packaging efficiency and easy control of the geometric errors during the assembly process. The deployment dynamics of a single rollable boom is studied via a dynamic model based on the variable-length thin shell element of absolute nodal coordinate formulation (ANCF) in the framework of arbitrary Lagrange-Euler (ALE) and the natural coordinate formulation (NCF), and verified via a deployment experiment. Meanwhile, the microgravity experiments for deployment, contraction, and geometric error control of an assembly module are also conducted on a granite platform with air bearings to demonstrate the performance of the deployable assembly module.

通过可部署模块进行在轨组装是建造大型空间结构的一种可行方法。本文从机械和电子两方面详细介绍了针对大型空间结构设计的可展开装配模块。该组装模块利用电机驱动的可滚动吊杆实现了较高的组装效率，并易于控制组装过程中的几何误差。在任意拉格朗日-欧拉（ALE）和自然坐标系（NCF）框架下，通过基于绝对节点坐标系（ANCF）的变长薄壳元素动态模型研究了单个可滚动吊杆的展开动力学，并通过展开实验进行了验证。同时，还在带空气轴承的花岗岩平台上进行了装配模块的展开、收缩和几何误差控制的微重力实验，以证明可展开装配模块的性能。

引用次数: 0

A treatment of the all-clear problem for solar energetic particle events and subsequent decision making 太阳高能粒子事件的 "万无一失 "问题处理及后续决策

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-21 DOI: 10.1016/j.actaastro.2024.09.040

We discuss the relatively overlooked problem of All Clear in Solar Energetic Particle (SEP) event prediction. These proton and heavier ion events are injected in major solar eruptions, propagate directionally into the heliosphere at relativistic speeds and threaten equipment and personnel at low-Earth orbit and beyond. SEPs are rare to extreme events associated with solar flares and coronal mass ejections (CMEs), with one SEP event detected in-situ every several hundreds of flares and CMEs observed remotely. This abysmal overall association improves drastically to below 1:2 for fast (i.e., shock-fronted) and halo (i.e., propagating mainly along the Sun–Earth line) CMEs. All Clear implies an assessment of tolerable conditions within a preset prediction window. Relying on one of the most comprehensive data sets for SEP events, we implement a methodology that provides an All Clear for events of NOAA severity S1 and above (S1+) and identify the minimal eruption attributes (flare size and CME speed) that could give rise to such SEP events from source locations in the Sun. The results correspond to and reflect settings of minimum complexity, giving rise to different attributes for different longitudinal zones in the earthward solar hemisphere. This work presents proof of concept; complexity can be increased at will for more demanding All Clear definitions, subject only to sufficient statistics due to the scarcity of the phenomenon. At this point, feedback is desired from stakeholders on what fits their definition of All Clear (we expect different definitions from different operators), so that to define the precise settings on which to run this and similar exercises.

我们讨论了在太阳高能粒子（SEP）事件预测中相对被忽视的 "一切正常 "问题。这些质子和重离子事件在太阳大爆发时注入，以相对论速度定向传播到日光层，威胁低地轨道及更远处的设备和人员。SEP 是与太阳耀斑和日冕物质抛射（CMEs）相关的罕见至极端事件，每数百次耀斑和 CMEs 的远程观测中就有一次 SEP 事件被现场探测到。对于快速（即冲击面）和日晕（即主要沿日地线传播）CMEs，这种糟糕的总体关联度会急剧降低到 1:2 以下。所有的 "清除 "都意味着要对预设预测窗口内的可容忍条件进行评估。依靠最全面的 SEP 事件数据集之一，我们实施了一种方法，为 NOAA 严重度 S1 及以上（S1+）的事件提供 "全部清除"，并确定了可能从太阳中的源位置引发此类 SEP 事件的最小爆发属性（耀斑大小和 CME 速度）。结果对应并反映了最小复杂度的设置，在向地太阳半球的不同纵向区域产生了不同的属性。这项工作证明了这一概念；对于要求更高的 "All Clear "定义，可以随意增加复杂度，但由于该现象的稀缺性，只需要足够的统计数据。在这一点上，我们希望利益相关者提供反馈意见，说明什么符合他们对 "全清楚 "的定义（我们希望不同的运营商有不同的定义），以便确定运行这项工作和类似工作的精确设置。

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引用次数: 0

Side and front fast imaging of solid and liquid fed ablative pulsed plasma thruster’s discharge 固体和液体馈入烧蚀脉冲等离子推进器放电的侧面和正面快速成像

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-21 DOI: 10.1016/j.actaastro.2024.09.025

Ultra-fast camera imaging is used to capture temporal evolution of the plasma discharge in an ablative Pulsed Plasma Thruster (PPT) fueled with solid polytetrafluoroethylene (PTFE) and liquid perfluoropolyether (PFPE), with the goal of comparing the mechanism of the expelled mass acceleration and getting insight into the physics of the processes involved in the discharge maintenance and impulse bit production. The fast photos are taken from two viewpoints (non-simultaneously), directing camera parallel (side view) and perpendicular (front view) to the ablative surface of the propellants, and are correlated with the relevant phases of the discharge current. Side view images reveal the presence of two distinct exhaust fractions, velocities of which differ by an order of magnitude. The speed of the faster fraction is comparable with the median of the ionized particles velocity expelled by the thruster. The vividness of the slow propagating component of the ablated mass, which mostly corresponds to neutral particles (based on velocity estimation) and lower mass bit of PFPE shots hint towards better propellant utilization by a liquid-fed PPT. Front view images confirm stable localization of PFPE discharge, forced by design of the propellant supplying plenum, whereas PTFE discharge is characterized by irregular path that covers an area of the propellant surface in random. The last half-period of the discharge is accompanied by vortices near the cathode spots. They are supposedly formed by evaporated electrode’s material and their trajectories imply further recombination in collisions with the electrodes, making this part of evaporated copper undetectable for charged particles diagnostics.

利用超快相机成像技术捕捉以固体聚四氟乙烯（PTFE）和液体全氟聚醚（PFPE）为燃料的烧蚀型脉冲等离子推进器（PPT）中等离子体放电的时间演变过程，目的是比较放电质量加速的机理，深入了解放电维持和脉冲位产生过程的物理原理。快速照片从两个视角（非同时）拍摄，相机分别平行于（侧视图）和垂直于（正视图）推进剂烧蚀表面，并与放电电流的相关阶段相关联。侧视图像显示存在两种不同的排气碎片，其速度相差一个数量级。速度较快的部分与推进器排出的电离粒子速度中值相当。烧蚀质量中的慢速传播部分非常明显，主要是中性粒子（根据速度估算），而全氟聚醚喷射的质量位数较低，这都暗示着以液体为燃料的 PPT 能更好地利用推进剂。正视图像证实了全氟聚醚放电的稳定定位，这是由推进剂供应腔的设计决定的，而聚四氟乙烯放电的特点是路径不规则，随机覆盖推进剂表面的一个区域。在放电的最后半周期，阴极点附近会出现涡流。它们应该是由蒸发的电极材料形成的，其轨迹意味着在与电极的碰撞中进一步重组，使得带电粒子诊断无法检测到这部分蒸发的铜。

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引用次数: 0

Ice-mining lunar rover using Americium-241 radioisotope power systems 使用镅-241放射性同位素动力系统的冰矿月球车

IF 3.1 2区物理与天体物理 Q1 ENGINEERING, AEROSPACE

Acta Astronautica

Pub Date : 2024-09-21 DOI: 10.1016/j.actaastro.2024.09.042

Permanently Shadowed Regions (PSRs) of the Moon contain rich deposits of water ice. They are very valuable to the space community as in-situ extracted water can be used for many purposes, such as propellant production and human habitat support. PSR craters never see sunlight, therefore solar power is not available there. They also present a cryogenic environment with regolith as cold as 40 K. These challenges can be overcome by employing a Radioisotope Power System (RPS) to provide both thermal and electrical power to resource extraction systems in the PSRs. The work presented here aims at characterizing an ice-mining lunar rover. The rover will be equipped with an Americium-241 (or ²⁴¹Am) based RPS. ²⁴¹Am has a 432-year long half-life and can provide decades of stable power output for the rover operations. The innovation lies in the fact that the RPS will not only provide electrical power to the rover, but that its waste heat will be employed to thermally mine ice from its deposits. The rover is equipped with a sublimation plate irradiating the underlying regolith to sublimate ice contained within, and with a cold trap where extracted volatiles will be deposited. This work studied the rover concept feasibility and developed a model of its Thermal Management System (TMS) to meet sublimation plate and cold trap temperature requirements. The results have been validated by a 3D finite element method thermal simulation for icy regolith conditions of 0–10 vol% water-ice content. The findings of this work suggest that it is possible to perform thermal ice-mining in the lunar PSR environment with an RPS-powered rover, with different degrees of efficiencies depending on the amount of ice in the deposits.

月球的永久阴影区（PSRs）蕴藏着丰富的水冰。它们对太空界非常宝贵，因为原地提取的水可用于多种用途，如推进剂生产和人类居住地支持。PSR 环形山从未见过阳光，因此无法利用太阳能。采用放射性同位素动力系统（RPS）为 PSR 中的资源提取系统提供热能和电能，可以克服这些挑战。本文介绍的工作旨在描述冰矿月球车的特征。月球车将配备基于镅-241（或 241Am）的 RPS。241Am 的半衰期长达 432 年，可为漫游车的运行提供数十年的稳定动力输出。创新之处在于，RPS 不仅能为漫游车提供电力，还能利用其余热从冰矿床中进行热开采。漫游车配备了一个升华板，通过辐照底层岩石使其中的冰升华，还配备了一个冷阱，提取的挥发物将沉积在冷阱中。这项工作研究了漫游车概念的可行性，并开发了一个热管理系统（TMS）模型，以满足升华板和冷阱的温度要求。在水冰含量为 0-10 Vol%的冰质碎石条件下进行的三维有限元法热模拟验证了这一结果。这项工作的研究结果表明，在月球PSR环境中使用RPS驱动的漫游车进行热采冰是可能的，根据矿床中冰的数量不同，效率也不同。

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引用次数: 0