Coupling-fluid heated bubble pump generators: Experiments and model development
Coupling-fluid heated bubble pump generators: Experiments and model development
复制标题
耦合流体加热气泡泵发生器：实验和模型开发
DOI：
--
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
S. Garimella
中科院分区：
文献类型：
--
作者：
A. Rattner;S. Garimella
单压吸收热泵仅使用热输入运行，是分布式冷却应用的理想候选者。这类系统中的液体循环通常是通过点加热的泡沫泵发电机来实现的，这种垂直管内有强烈的局部热来解吸制冷剂。不断上升的制冷剂气泡将溶液提升到上层储液池，该储液池为其他系统组件提供燃料。虽然这种制冷剂分离和流体循环的方法很简单，但它需要高级能源，因此不能在许多环境中使用。在这项研究中，研究了一种全长耦合流体加热泡沫泵发电机。在这种实施方式中，加热液通过气泡泵管周围的环形夹套循环。由于换热面积比传统的点加热泡沫泵发电机大得多，因此可以使用相对较低的热源。给出了一台内径为7.8 mm的水蒸气混合工质鼓泡泵发生器在不同工况下的实验研究结果。这种气泡泵发电机可以在比流体饱和温度高出11K的温度下工作。建立了流体力学流动与换热模型，并进行了验证。这项研究表明，耦合流体加热的泡沫泵发电机是一种很有前途的替代传统的点加热装置，并且可以使用低品位热能进行制冷。
Single-pressure absorption heat pumps operate using solely thermal input and are ideal candidates for distributed cooling applications. Liquid circulation in such systems has conventionally been achieved with spot-heated bubble-pump generators, vertical tubes in which intense localized heat desorbs refrigerant. Rising refrigerant bubbles lift solutions to an upper reservoir, which feeds other system components. While this method of refrigerant separation and fluid circulation is simple, it necessitates a source of high-grade energy and thus cannot be employed in many settings. In this investigation, a full-length coupling-fluid heated bubble-pump generator is investigated. In this implementation, heating fluid is circulated through an annular jacket around the bubble-pump tube. Because the heat transfer area is much larger than in conventional spot-heated bubble-pump generators, relatively low-temperature thermal sources can be employed. Results are presented from an experimental study of a 7.8-mm-internal-diameter bubble-pump generator with water-steam working fluid over a range of operating conditions. This bubble-pump generator can operate with thermal input as low as 11 K above the fluid saturation temperature. A mechanistic fluid flow and heat transfer model is developed and validated. This investigation demonstrates that coupling-fluid heated bubble-pump generators are a promising alternative to conventional spot-heated implementations and can enable refrigeration using low-grade thermal energy.