气波引射器反馈结构的功能机理及性能实验

Functional mechanism and performance of gas wave ejector feedback structure

气波引射器是一种利用气体压力波实现能量交换过程的新型动态设备,因其具有效率较高、结构简单以及能耗低等优点,在诸多生产过程中具有广阔的应用前景。为提升气波引射器在中压背压较高工况下的应用性能,提出了一种简单易行的反馈结构,并对其功能机理与性能进行了模拟及实验研究。通过数值模拟考察了此结构通过预压缩作用来削弱反向压缩波不良影响的功能机理,得出此结构的适用条件以及应用效果判定条件。通过实验验证了数值模拟的正确性,并获得了反馈结构的实际应用效果。实验范围内,反馈结构获得的最大效率及引射率提升量分别可达6.93%和5.43%。

The gas wave ejector is a new type of dynamic equipment that uses gas pressure waves to realize the pressure energy exchange process. Because of high efficiency, simple structure and low energy consumption, the gas wave ejector has broad application prospects in many production processes.According to the working principle of this equipment,the reversed compression waves formed at the medium pressure port could result in a large decrease of the equipment performance or even lead to the loss of function at high medium backpressure. Therefore, aworkable feedback structure was proposed in this work to optimize the performance of the gas wave ejector by avoiding the formation of redundant compression waves under high medium backpressure conditions. The functional mechanism and performance of this structure were studied in detail by numerical simulation and experimental methods. By means of numerical simulation, the functional mechanism of the feedback structure to weaken the reversed compression waves through pre-compression was demonstrated. Meanwhile, the effective and evaluating criteria of this structure were proposed by the results of numerical simulation. To ensure the efficient operation of this structure, the minimum pressure in the flow channel of the stable-pressure region should be less than the medium port backpressure. And the efficiency improvement of this structure was positively correlated with the average pressure difference in the flow channel of stable-pressure region with or without feedback structure. By the experimental methods, the correctness of the numerical simulation was verified, and the actual application consequence of the feedback structure was obtained. By the application of this feedback structure, the maximum lifting capacity of equipment efficiency and ejection rate could reach about 6.93% and 5.43%, respectively. The investigation results demonstrated that the feedback structure was easy to implement and supplied a positive application effect under high medium backpressure conditions, which proved its promising application value.