These authors were considered to conduct the research from redesigned injector for simulation models and, it is aimed at presenting the visualized study results to allow improvement prediction on mass flow based on distributing design within a low- and high-pressure injector for NGV. An injector model of NG was designed by spring, sleeve and forth hole and, the plunger inside injector was manufactured by material of SUS 401 from plunger assay. Also, these models based on part of components were redesigned to calculate mesh size of simulation through CFX program, which can modify the flow layer in NG injector. The performance result of stroke of 0.100mm and 0.200mm from high-pressure (Hp) can verify the gas flow which was changed at the neck area in models (b), (c), (d) and (e), and the changed velocities were increased in all the models on account of the flow rate, which could be accommodated inside the plunger to maintain the optimum state as the high-pressure flown in inlet of the injector.

natural gas, high injection, low injection, diffusion, velocity.