发动机废气文丘里流量计回流结构应用分析

安宁，姚旺，张晨，栾军山

潍柴动力股份有限公司，山东 潍坊  261061

摘要：为提高废气文丘里流量计测量精度和边界适应性，对比不同废气测量方式，分析文丘里流量计结构及测量原理，设计具有回流测量结构的文丘里流量计，通过发动机台架试验对比分析有、无回流结构的文丘里流量计的测量精度和边界适应性。结果表明：有回流结构的文丘里流量计测量精度高于无回流结构，无回流测量结构的文丘里管的修正脉谱最小标定因数为0.5，有回流测量结构的文丘里管的修正脉谱标定数系数为0.9~1.1；无回流结构的文丘里流量计无法准确测量排气脉冲状态；有回流结构文丘里流量计适用于发动机不同的运行模式，有较高的边界适应性。

关键词：文丘里管；回流结构；测量精度；边界适应性

Application analysis of measured backflow structure of exhaust Venture tube

AN Ning, YAO Wang, ZHANG Chen, LUAN Junshan

Weichai Power Co.,Ltd.,Weifang 261061，China

Abstract：In order to improve the measurement accuracy and boundary adaptability of the exhaust gas Venturi flowmeter, different exhaust gas measurement methods are compared, and the structure and measurement principle of the Venturi flowmeter are analyzed, a Venturi flowmeter with backflow measurement structure is designed. The measurement accuracy and boundary adaptability of Venturi flowmeter with and without backflow structure are then compared and analyzed through engine bench test. The results show that the measurement accuracy of the Venturi flowmeter with backflow measurement structure is higher. The minimum calibration factor of the modified pulse spectrum of the Venturi without backflow measurement structure is 0.5, and the calibration number coefficient of the modified pulse spectrum of the Venturi with backflow measurement structure is 0.9~1.1. The Venturi flowmeter without backflow measurement structure cannot accurately measure the exhaust pulse state, the Venturi flowmeter with backflow measurement structure is applicable to different operating modes of the engine and has high boundary adaptability.

Keywords:Venturi tube;backflow structure; measurement accuracy; boundary adaptability