Study of the Injection Flow of Single-channel Single-injection and Dual-channel Dual-injection of Thermal Bubble Micropump on Locomotive Fuel Atomization System

摘要

This study applies thermal bubble micropump to the injector of the fuel atomizer of motorbike, and uses Stoddard solvent as work fluid to conduct numerical simulation flow analysis on single-channel single-injection and dual-channel dual-injection data, in order to compare the speed, shape, and path of the injected droplet, the internal flow of the micropump, and work fluid replenishment after injection. The diameter of the injection head is 50 μ m, make and move frequency is 5kHz. The work fluid and external air is incompressible fluid. The governing equations are conservation equation of mass and momentum. Volume-Of-Fluid (VOF) method is used to discretize the size and motion path of the injected droplets. Finite Volume method is used to disperse the governing equation, then SIMPLEC algorithm is used for solution procedure. The result shows that in dual-channel dual-injection case, the injectors, due to separate connection to convergent and divergent replenish channel, the different pressure of replenish channel exerted during the injection process leads to different injection speed, as well as length and shape of droplets. During the replenish process, the dual-channel dual-injection test object uses different channels for convergent and divergent replenishment. Therefore, dual-channel dual-injection results in superior fluid replenish rate than that of single-channel single-injection.