基于层流流量计的航发燃油流量动态测量技术研究

为解决航空发动机过渡态燃油测量问题,研究了基于层流流量计(LFM)的航空燃油流量动态测量技术。设计了一款量程为0～3 000 mL/min的液体LFM,在小型涡轮喷气式发动机试车台上对其进行了试验,并与科里奥利流量计(CMF)进行了比对,试验结果显示LFM具有优秀的动态特性。当发动机处于稳态时,LFM测量结果与CMF吻合较好,相对误差为-1.25%～1.16%,与LFM校准时-1.24%～1.26%的相对误差相吻合。当发动机处于过渡态时,LFM能很好地跟随泵后油压,而CMF则无法跟随泵后油压,存在大约2 s的滞后。LFM的测量结果能与发动机起动、加/减速时的控制逻辑保持一致。本文研究可为航空发动机试车技术的研究和LFM应用的拓展提供有价值的参考。

Research on fuel dynamic flow measurement technology for aero-engine based on laminar flow meter

In order to solve the problem of aero-engine fuel measurement in transient state, the dynamic flow measurement technology of aero-fuel flow based on laminar flow meter (LFM) was studied. A liquid LFM with a range of 0~ 3 000 mL/ min was designed. The LFM was tested on a small turbojet-engine test bench and compared with a coriolis mass flowmeter (CMF). The test results show that the LFM has excellent dynamic characteristics. When the engine is in a steady state, the LFM measurement results are in good agreement with those of the CMF, and the relative error is -1. 25% ~ 1. 16% , which is consistent with the relative error of -1. 24% ~ 1. 26% when the LFM is calibrated. When the engine is in a transition state, the liquid LFM can follow the oil pressure after pump well, while the CMF cannot follow the oil pressure after the pump and there is a lag of about 2 s. The measurement result of the LFM can be consistent with the control logic during starting and acceleration / deceleration. The study in this paper provides valuable references for the research of aero-engine test technology and the expansion of LFM applications.