Abstract

Creare is developing a miniature, low-power, free-piston energy conversion system. Our converter is designed to transform thermal energy from radioisotope heater units into on-demand electricity essential to space exploration probes, unmanned surface rovers, small landers, small satellites, and similar small-scale systems operating in darkness. We have achieved a simple system design with a single moving part that requires no recuperator and no regenerators or valves. Our converter technology promises a high-efficiency system in an extremely compact enclosure. This work describes preliminary design, analysis, and testing efforts for our miniaturized converter. We fabricated a laboratory-scale prototype and acquired experimental data at prototypical temperatures to validate our performance models. Our numerical model was able to accurately predict converter losses. In doing so, we also demonstrated the feasibility of our novel thermodynamic cycle through the generation of net positive pressure-volume work of the system at its design temperature (~873 K). These results have been used to guide subsequent converter design modifications. Future work includes the fabrication, testing, and detailed performance assessment of a complete prototype converter.

摘要

Creare正在开发一种微型，低功率，无活塞的能量转换系统。我们的转换器旨在将热能从放射性同位素加热器单元转换为按需电力，这对于太空探测探头，无人水面漫游车，小型着陆器，小型卫星以及在黑暗中运行的类似小型系统至关重要。我们已经实现了具有单个运动部件的简单系统设计，该运动部件不需要换热器，也不需要再生器或阀门。我们的转换器技术有望在一个极为紧凑的外壳中实现高效系统。这项工作描述了我们的小型转换器的初步设计，分析和测试工作。我们制造了实验室规模的原型，并在原型温度下获取了实验数据以验证我们的性能模型。我们的数值模型能够准确预测转换器损耗。在此过程中，我们还通过在系统设计温度（〜873 K）下产生净正压-体积功来证明我们新颖的热力学循环的可行性。这些结果已用于指导后续转换器设计的修改。未来的工作包括完整原型转换器的制造，测试和详细的性能评估。