排气扩压器极限点流动模式分析及引射器工作状态特性

根据试验实测的引射器极限工作点数据,分析了引射器初始段内主动射流输运特性对极限点工作参数的重大影响,提出了引射器极限工作点的实际流动模式,剖析了引射器极限膨胀比不可逾越性。从理论和试验证明,引射器在抽除射流输运质量的条件下,可以将使用膨胀比提高到远远超过极限膨胀比的广阔区域。首次获得了从低膨胀比到超越极限膨胀比限制的高膨胀比的“引射器工作状态试验特性”。 

LIMIT POINT FLOW MODE ANALYSIS OF EXHAUST DIFFUSER AND OPERATION CHARACTERISTICS OF INJECTOR

This paper analyzes the great effect of injection transfer characteristics on limit point operation parameters in an injector and flow character of injected flow according to injector limit point data measured in tests of Science Foundation Subject No.24001.The actual flow mode at injector limit point is presented.The paper also analyzes the impassability of limit expansion ratio for the injector and the reason why the limit expansion ratio calculated from the injector engineering method is much less than its value obtained from the tests.The eyisting conclusion that “the injector limit expansion ratio is the highest possible pressure ratio” is refuted by the theoretical demonstration and injector operation characteristics measured in tests.It is proved that the operational expansion ratio can be increased much beyond the limit expasion ratio when the injector absorbs injection transfer mass.The “Operation test characteristics of injector” from low expansion ratio to high expanion ratio beyond the limit expansion ratio is first accomplished.