Influences of key design parameters to operating performance of a compressed natural gas injection system using solenoid pressure regulator

Abstract

A study is carried out to examine the effects of design parameters on operating performance of a compressed natural gas (CNG) injection system. This system consists of a solenoid-type injector, a solenoid pressure regulator, and a rail tube. To depict the operation of the injection system, mathematical models are built, including electrical and mechanical models of a solenoid pressure regulator and a solenoid injector. To control rail tube gas pressure, a control model is built using proportional integral derivative (PID) algorithm. The simulated gas pressure is compared with experimental result for validating the mathematical models. The influences of design parameters, including rail tube volume, stiffness of spring, and number of coil turns in the solenoid pressure regulator, on the operating performance of the CNG system are examined. The simulation results indicate that the stability of controlled gas pressure is increased when increasing the volume of the rail tube and spring stiffness. Besides, by decreasing the number of coil turns in the solenoid pressure regulator, the stability of controlled gas pressure and flow rate of the injection is increased.