余热制冷装置中氨吸收器热、质耦合数值研究

Study on Coupled Mass and Heat in Absorption Refrigerating Device Using Waste Heat

船用柴油机废热品位较高,基本满足吸收式制冷装置的需要。作为吸收式制冷装置中重要的部件,吸收器的合理设计直接决定了制冷系统的综合性能。在对水平管氨降膜吸收器中传质与传热的相互关系进行详细分析的基础上,建立了完全基于热、质耦合传递的二维模型。数值计算结果表明,在氨降膜吸收过程中,强烈的传质过程是实质,起着主导作用,而传热过程仅是传质过程的外在表现。

The quality of the waste heat exhausted from diesel engine in vessels is high, which means it is possible to utilize waste heat in an ＂absorption refrigeration device as heat resources. As one of the most important components, proper design of the absorber is a key way to improve the integrative performance of the refrigerating system. With the detailed analyses about the mutuality between the mass and heat transfer in a horizontal falling film ammonia-water absorber, a new 2-D model based on the coupling of the mass ＆ heat transfer is introduced. Numerical results indicate that the mass transfer is dominant and the heat transfer is just the extrinsic exhibition.