基于虚拟仪器技术的发动机油耗测试系统研究

针对传统油耗仪的缺陷,利用虚拟仪器技术设计了一种发动机油耗测试系统.该系统是在原有发动机性能检测系统基础上扩充的一种智能化瞬态油耗仪系统,由重量传感器、油箱、充油电磁阀及各路油管组成.重量传感器输出的信号经信号调理电路输入6024E的模拟通道,经计算机分析处理;充油电磁阀的控制信号由6024E的数字通道输出,将油路切换成充油状态和测量状态.设计中主要结合失重原理和瞬时流量概念,使系统不仅有较高的测量精度,还能实时显示瞬时油耗和平均油耗.利用虚拟仪器技术将油耗仪与发动机性能测控系统有机地结合在一起,使系统不仅可实时显示发动机检测过程中的转速、扭矩和功率波形,还可实时显示发动机做变工况实验时的转速、扭矩、功率与瞬时油耗率的变化曲线.

Studies on engine fuel consumption measuring system based on virtual instrument technology

In view of the defect of the traditional measurement,this paper introduces a new engine fuel consumption measuring system developed using virtual instrument technology.Based on the previous engine test system,the new system described in this paper is evolved.An engine transient-fuel-consumption intelligent meter is included as an extra part,which is comprised of weight sensor,fuel tank,fuel-filling electromagnetic valve,and other fuel pipes.The signal output from the weight sensor is transmitted to one of the analog channels of PCI-6024E board by conditioning circuit.The control signal of the electromagnetic valve is sent out from one of the digital channels of the PCI-6024E board,and the fuel pathway is switched from fuel-filling state to measuring state or vice versa.The design idea of the transient-fuel-consumption meter is based on the weightlessness principle and instantaneous flow survey conception,so the system can not only measure the fuel consumption with high accuracy,but also display the real-time instantaneous fuel flow and mean fuel flow.Using the LabVIEW,the engine test system has been integrated with this transient-fuel-consumption meter,so it can show the real-time wave of rotation speed,torque and power during the testing phase,and get a continuous curve reflecting the change in real-time rotation speed,torque,power offering and instantaneous fuel consumption rate during variable work condition test.