西南石油大学学报(自然科学版)

• 石油机械工程及其他 • 上一篇    下一篇

燃气发动机动力缸压力计算方法与测试分析

田家林1,2,朱永豪1,杨琳1,庞小林1,李友1   

  1. 1. 西南石油大学机电工程学院,四川成都610500
    2. 西南交通大学机械工程学院,四川成都610031
  • 出版日期:2014-08-01 发布日期:2014-08-01

Pressure Calculation and Test Analysis of Natural Gas Engine Power Cylinder

Tian Jialin1,2, Zhu Yonghao1, Yang Lin1, Pang Xiaolin1, Li You1   

  1. 1. School of Mechatronic Engineering,Southwest Petroleum University,Chengdu,Sichuan 610500,China
    2. School of Mechanical Engineering,Southwest Jiaotong University,Chengdu,Sichuan 610031,China
  • Online:2014-08-01 Published:2014-08-01

摘要:

燃气发动机工作过程动力缸的压力计算,是保证发动机安全运行、进行机组关键部件力学性能计算与安全评价的基础。根据燃气发动机工作原理与热力学过程,完成气体状态方程与燃烧过程分析,根据质量方程、动量方程与能量守恒方程,建立燃烧过程压力计算方法;利用双区模型条件与现场测试结果,确定燃烧率计算公式;对于多变指数,根据建立的数据库,利用软件计算模块确定数值,保证计算精度,避免了人为因素对计算结果的影响。最后通过算例分析与现场测试结果的分析,验证了计算方法的可靠性。利用建立的压力计算方法,可进行燃气发动机工作过程点火提前角、空燃比、转速、温度等关键参数对压力影响的定量分析;同时,利用压力计算结果进行发动机效率分析,可为机组经济运行提供计算基础;利用压力计算结果进行发动机关键件力学分析,可为机组安全评价提供理论支撑。

关键词: 天然气, 发动机, 动力缸, 热力学, 压力, 计算方法

Abstract:

Pressure calculation of the natural gas engine power cylinder in working process is the basis of ensuring engine operation,and mechanical properties calculation and safety evaluation of the key components. According to the gas engine working principle and thermodynamic process,this article analyzes the gas state equation and the gas combustion process. Based on the mass equation,momentum equation and energy conservation equation,the combustion process pressure calculation method is established. Using the two-region model and field test results,the gas combustion rate equation is presented. As for the polytropic exponent,with the established database,this article determines the value with the software module,ensuring the accuracy and avoiding influence of human factors on the calculation results. Finally,with the numerical example and field test results analysis,the reliability of this calculation method is verified. Based on the pressure calculation method,quantitative analysis of the influence of key parameters such as the ignition advance angle,air-fuel ratio,speed and temperature on pressure is made. Meanwhile,using the pressure calculation results,the engine efficiency analysis can provide the basis for the economic machine operation. The mechanical performance calculation of key components based on the pressure calculation results,can provide theoretical support for safety evaluation of the engine.

Key words: natural gas, engine, power cylinder, thermodynamics, pressure, calculation method