Measurement of Film Thickness in Gas-Centered Swirl Coaxial Injectors

摘要

A number of study of Gas-Centered Swirl Coaxial(GCSC) injectors that have been used for stage-combustion cycle engine with high efficiency have been conducted in the last few decades. GCSC injectors that supply the oxidizer-rich gas generated from pre-burner is injected to the center of injectors in the form of jet. At the same time swirled liquid fuel is wrapped around the gas jet. The study was conducted to find the characteristics of spray varying the momentum flux ratio and recess ratio which are known as important parameter of coaxial injectors. This study measured the spray angle and film thickness of gas-centered swirl coaxial injector according to momentum flux ratio and recess ratio. The film thickness is measured by using electrical conductance method. Also the variation of spray angle was obtained by the backlight image method. It was found that the spray angle and film thickness were changed according to the critical momentum flux ratio.