Theoretical and Experimental Investigation for Liquid Film in an Impinging Stream Vortex Chamber

The paper, based on the special structural features and operation modes of impinging stream vortex engine, starts from the process that two jet flows impact each other and synthetic jet impacts solid wall leading to liquid film, to simplify complex flow process, establishes the calculation model between shape of adherent liquid film and jet conditions, builds the measurement system of adherent liquid film forming when synthetic jet impacts solid wall and finished the experimental verification of liquid film calculation model. The research shows that (1) as impact angle increases, the speed of synthetic jet gradually decreases, the longitudinal area of adherent wall increases and the possibility of liquid film breaking increases; (2) the experimental result of shape of liquid film shows that the calculated result of liquid film analysis model is basically in line with the actual situation with the errors controlled in 10%; (3) the measurement method of thickness of liquid film adopting image subtract operation has a high precision. It is verified that the measurement precision of thickness of system reach 0.01mm, its measurement error is lower than 5% and it can be used to measure the thickness of adherent liquid film inside thrust chamber.