摘要: |
吸收器是吸收制冷系统中的关键部件之一,吸收性能的好坏直接关系着整个制冷系统的性能。作为一种重要的吸收方式,绝热喷雾吸收将吸收工质通过喷嘴在冷剂蒸汽中形成微米级的液滴,进而形成巨大的气液接触面积,可以极大地提高吸收速率。在Newman模型的基础上,考虑吸收热对吸收过程中的影响,一个改进的绝热喷雾吸收模型被建立。借助此模型,对氨水绝热喷雾吸收过程进行性能分析。结果显示,吸收时间的延长可以提高吸收量MA,但是当t/tMax达到0.6,吸收量MA达到了最大吸收量的90%,即过分延长吸收时间不是一个经济的强化方法。最大吸收时间与液滴半径的平方成正比,即半径的减少可以提高喷雾吸收效率,但半径的减少会增加系统的能耗。研究结果将为高效绝热喷雾吸收器的设计提供理论参考。 |
关键词: 吸收制冷 氨水 模型 绝热喷雾吸收 |
DOI: |
投稿时间:2012-10-10
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基金项目:国家自然科学基金(51006013)和中央高校基本科研业务费专项资金(2011JC003)资助项目 |
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Characteristic Analysis of Adiabatic Spray Absorption Process in Aqueous Ammonia Solution |
Su Fengmin,Deng Yangbo,Gao Hongtao |
(Institute of Marine Engineering and Thermal Science, Dalian Maritime University) |
Abstract: |
An absorber is a key device of absorption refrigeration system, and it directly affects the performance of refrigeration system. As an important absorption type, adiabatic spray absorption process disperses the absorption fluid into fine droplets by nozzles and forms immense surface exposed to the coolant vapor. Therefore, it can improve the absorption performance. In the paper, an improved analytical Newman model is presented which can consider the absorption heat effect on adiabatic spray absorption process. Using the model, the absorption characteristics of the adiabatic spray in aqueous ammonia is studied. The results show that increasing absorption time can increase absorption mass, MA. However, when t/tMax approaches to 0.6, MA has reached to 90% of the maximum absorption mass. In other words, increasing absorption time can hardly improve MA aftert/tMax exceeds 0.6. The maximum absorption time, tMax, is proportional to the square of the droplet radius. Decreasing droplet radius can improve the absorption rate,but this increases the energy consumption of the refrigeration system. The current investigation can result in a better understanding of absorption mechanisms of the adiabatic spray absorption. |
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