工程机械排气引射管优化设计

Optimization Design of Exhaust Ejector Tube for Construction Machinery

本文论述了排气引射管的各阶固有频率和模态振型计算方法。建立了某款工程机械排气引射管的声学计算模型,计算了其固有频率并分析了引起共鸣的原因,开展了结构参数的优化设计。计算结果表明:排气引射管的一阶固有频率与排气脉冲频率基本符合,存在共鸣现象,使排气噪声增加,改变引射管长度对引射管声腔一阶固有频率的影响较增大直径效果明显;通过优化设计使排气与引射管的共鸣转速在1300rpm附近,削减了共鸣对排气噪声的影响,缩短了引射管减轻了振动。为工程机械排气排气引射管优化设计提供了一定基础。

In this paper, the natural frequencies and mode shapes of exhaust ejector tubes are discussed. An acoustic calculation model of an exhaust pipe of a construction machinery is established, its natural frequency is calculated, the cause of resonance is analyzed, and the optimum design of structural parameters is carried out. The calculation results show that the exhaust ejector tube of the first order natural frequency and the exhaust pulse frequency line, resonate phenomenon, make the exhaust noise increase, change the lead effects of radio tube length on ejector tube cavity of first-order natural frequency with increasing diameter obviously; through the resonance speed optimization design of the exhaust and the ejector tube is at near 1300 rpm, to reduce the impact echo on the exhaust noise, shorten the ejector can reduce the vibration. It provides a basis for the optimization design of exhaust ejector pipe of construction machinery.