关键词: 低压喷射, 定容弹, 甲醇, 流量特性, 射流特性

Abstract: An experiment of spray characteristics of 3 types injector low-pressure injection using methanol under various ambient pressure is investigated in constant volume bomb using high speed photograph method. Single spray methanel mass under various ambient pressure of 3 types injector is measured. Matlab software is used to process digital images, and macroscopical spray characteristic parameters, such as spray penetration, spray cone angle, are measured. The results show that the methanol spray penetration, spray cone angle and single spray methanol mass decrease with the increase of the ambient pressure. When the ambient pressure increases above 0.15 MPa, methanol spray penetration reduces rapidly. The methanol spray cone angle which is big at the initial of spray, decreases with the increase of time and declines to 3.8º in the end. Variations of methanol spray mass flow-rate of 3 types injector with different ambient pressure meet Bernoulli’s equation. The methanol spray mass flow-rate of two-hole injetor and four-hole injetor are bigger than the result deduced from Bernoulli’s equation .When the ambient pressure increases to 0.3 MPa, which is equal to injection pressure, methanol spray mass tends to a constant number with the increase of spray time.

Key words: Constant volume bomb, Jet characteristic, Low pressure injection, Mass flow-rate characteristic, Methanol