摘要
为实时获取柴油机工作过程中喷油器喷嘴流量系数的动态变化过程,提出一种柴油机喷油器喷嘴流量系数在线测量方法.基于黎曼不变量理论将复杂的压力变化过程简化为黎曼单波的运动过程,并建立了喷油器入口压力与流量系数的数学关系.用压力二阶导数曲线的特征值确定4个压力单波W1、W2、W3和W4到达测量点的时刻.通过判断右行压缩波W3是否到达压力测量点,将喷射条件分为小喷油量条件和大喷油量条件.在小喷油量条件下对左行膨胀波W1进行解耦;在大喷油量条件下对W1与W3进行解耦,并提出两种条件下针阀运动时刻瞬态流量系数在线计算方法.结果表明:该方法所得出的瞬态流量系数曲线与试验台实测获取的瞬态流量系数曲线的拟合精度达到0.9300以上,计算的平均流量系数与实测平均流量系数的误差不超过5%,该方法有较高的精度.
An on-line measurement method of the discharge coefficient of the injector nozzle was presented in order to obtain the dynamic change process of the discharge coefficient in real time of a diesel engine operation.Based on the Riemann invariant theory,the complex pressure change process was simplified as an evolution process of the Riemann wave.A mathematical relationship between the inlet pressure and the discharge coefficient was established.The eigenvalues of the second derivative curve of pressure were used to determine the time when the Riemann single waves of W1,W2,W3 and W4 reach the measurement point.By judging whether W3 reaches the measuring point,the injection conditions were divided into small injection quantity conditions and large ones.W1 was de-coupled under the small injection quantity situation,and W1 and W3 were decoupled under the large one.An on-line calculation method for transient discharge coefficient of needle valve movement under both injection quantity was proposed.The results show that the fitting accuracy of the transient discharge coefficient curve obtained by this method is over 0.9300,and the error between the calculated average discharge coefficient and the experimental one is less than 5%,indicating that this method has a high accuracy.
作者
周谈庆
金江善
杨晰宇
倪昊
董全
Zhou Tanqing;Jin Jiangshan;Yang Xiyu;Ni Hao;Dong Quan(College of Power and Energy Engineering,Harbin Engineering University,Harbin 150001,China;Shanghai Marine Diesel Engine Research Institute,Shanghai 201108,China)
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2022年第5期430-439,共10页
Transactions of Csice
基金
国家自然科学基金资助项目(51879056).
关键词
柴油机
喷油器
流量系数
在线测量
diesel engine
injector
discharge coefficient
on-line measurement
