高效船舶余热驱动双元工质喷射制冷混合机理研究

As a series of new IMO convention and regulation will go into effect gradually, the green and security field had been the focus of the global shipping industry research. So Ship waste heat ejector refrigeration as a green refrigeration technology had been widely concerned, which can effectively utilize the waste heat of exhauste gas and jacket water. However, it is restricted because the mixing mechanism is not clear and the system performance is low. Our research group exploratorily put forward that two kinds of different working medium had been adopt as the primary flow and secondary flow respectively in the ejector refrigeration system, to improve the performance. Based on PIV&V3V technology, the primary factors that affect the fluid flow characteristics and performance parameter of ejector will be investigated deeply and systematically by visual observation and measurement of flow field in the transparent ejector under the condition of obtaining the optimum binary refrigerants. The mixing mechanism of primary flow and second flow will be made clear completely and structural parameters of ejector will be optimized, thereby effectively improving the system performance.The theoretical basis and technical reserves will be provided in order to further develop effective energy-saving technology on the ship.

随着一系列更为严格的IMO新公约、新规则即将陆续生效，使得绿色安全领域成为全球航运业研究的焦点，船舶余热喷射式制冷作为一种能够有效回收船舶废气和缸套水余热的绿色制冷方式被广泛关注。但因其混合机理较为复杂，目前缺乏深入研究，同时现有工质的性能系数较低，致使喷射式制冷效率较低，限制了喷射制冷的广泛应用。本课题组探索性地提出了在系统中采用两种不同工质分别作为工作流体和引射流体，以提高工质的工作性能。在确定最佳双元工质参数条件下，采用理论建模、模拟分析和实验验证相结合的技术路线，基于PIV&V3V技术，通过对喷射式制冷系统透明喷射器的可视化观测和流场定量测量，深入系统地研究喷射器内部流体的流动特性和喷射器性能参数的主要影响因素。从而充分地揭示出喷射器内工作流体与引射流体的混合机理，实现对喷射器结构参数的优化，进而有效提高喷射式制冷性能，为进一步开发高效船舶节能技术提供理论依据和技术储备。

随着能源危机和气候变化问题日益严重，节能减排刻不容缓，航运业耗能巨大，提高船舶能效已成为研究热点。喷射制冷是一种能有效利用低品位热能、维修方便、系统可靠性高、可直接利用水等环保型制冷剂的“绿色制冷”方式，具有较高的研究价值和广阔的应用前景。但由于效率不高，制约了其广泛应用，如何提高喷射式制冷系统性能就成为当前研究的首要任务。本课题组采用理论建模、模拟分析和实验验证相结合的技术路线，基于PIV技术，通过对喷射式制冷系统透明喷射器的可视化观测和流场定量测量，深入系统地研究了喷射器内部流体的流动特性和喷射器性能参数的主要影响因素。以超音速气体动力学为理论基础，建立一维等压混合模型，用于喷射器的设计和性能分析；搭建了喷射式制冷系统透明喷射器实验台，利用PIV技术开展了喷射器内部工作流体与引射流体相互混合和特殊流动现象（激波）的研究；采用CFD方法开展喷射器结构尺寸参数和工况参数对喷射器内部工作流体与引射流体相互混合和特殊流动现象（激波）影响的模拟研究；搭建了喷射式制冷实验平台，开展了喷射器结构尺寸参数和工况参数对船舶余热喷射器性能影响的实验研究。本项目所开展的喷射式制冷混合机理及高效船舶低品位能源喷射式制冷技术研究不仅可以用于低品位能源制冷，同时对朗肯循环发电和海水淡化中喷射器的应用也具备参考价值。