Transport-Enhanced Thermogalvanic Energy Conversion

鉴于对能源效率和碳排放的重新重视，CBET-1236571费兰热能转换仍然是一个诱人的研究课题。固态热电器件已经得到了广泛的研究，但由于成本的原因，以及无法以易于与热源兼容的几何形状来制造它们，其实际应用仍然具有挑战性。固态热电设备的一个有趣的替代品是热电电池，它包括(通常)允许离子传输的液体电解液。热电偶电池在电化学界早已为人所知，但在热传输界却没有得到太多的关注。考虑到它们的性能高度依赖于控制热和质量(离子)传输，这是令人惊讶的。拟议的项目是机械工程(热运输)和化学之间的跨学科合作，主要是一项旨在改善对热电偶系统的基本理解的实验性工作。热和质量传输将通过在电极之间施加纳米结构膜来控制，这将利用先前的工作，这些工作证明了通过排列的碳纳米管电极的传质率非常高，而通过随机取向的碳纳米管的传热率非常低。这项工作可能会提高废热能量的转化，这主要是因为像热电偶电池这样的流体设备可以符合像排气管这样的热源的形状，而且因为热电偶电池的制造最终可能比类似的热电设备更便宜。最后，作为正在进行的Science is Fun计划的一部分，将开展一个广泛的K-12推广计划，在该计划中，4至8年级的学生将进行基于演示盐水中的热电效应的简单实验。

CBET-1236571PhelanWaste heat energy conversion remains an inviting subject for research, given the renewed emphasis on energy efficiency and carbon emissions reduction. Solid-state thermoelectric devices have been widely investigated, but their practical application remains challenging because of cost and the inability to fabricate them in geometries that are easily compatible with heat sources. An intriguing alternative to solid-state thermoelectric devices is thermogalvanic cells, which include a (generally) liquid electrolyte that permits the transport of ions. Thermogalvanic cells have long been known in the electrochemistry community, but have not received much attention from the thermal transport community. This is surprising given that their performance is highly dependent on controlling both thermal and mass (ionic) transport. The proposed project is an interdisciplinary collaboration between mechanical engineering (thermal transport) and chemistry, and is a largely experimental effort aimed at improving fundamental understanding of thermogalvanic systems. Both thermal and mass transport will be controlled by imposing a nanostructured membrane between the electrodes, which will take advantage of previous work that demonstrated very high rates of mass transfer through aligned carbon-nanotube electrodes, and very low rates of heat transfer through randomly oriented carbon nanotubes. This work may enable improved waste heat energy conversion, largely because a fluidic device like a thermogalvanic cell can conform to the shape of a heat source like an exhaust pipe, and because thermogalvanic cells may ultimately be manufactured more cheaply than comparable thermoelectric devices. Finally, an extensive K-12 outreach program will be undertaken as part of the ongoing Science is Fun program, in which simple experiments based on demonstrating the thermogalvanic effect in salt water will be carried out by students in grades 4 through 8.