Study on the characteristics of gas jet for engine using high speed photography

A study on the movement of the gas jet is shot in real-time by the high speed photography and disposes the images with the professional software Image-Pro6.3. The author selects the vertex of the gas jet as a subject investigated to research the variation of the jet penetration, the jet dispersion angle and the jet velocity along with the jet time according to the theory of the free jet. The results show that: the gas jet development process is divided into two stages: the initial section and the main section. When the rotational speed of the engine is a definite value along with the jet time, the jet penetration increases, the jet dispersion angle remains unchanged and the jet velocity decreases. When the rotational speed increases, the jet penetration and jet velocity reduce, but the jet dispersion angle raises, then determines the mathematical model between the jet velocity and the jet penetration on this basis.