DIFFERENT CONDITIONS OF THE ROUND HYDROGEN JETS DIFFUSION COMBUSTION IN AIR

Read more The purpose of this work is experimental study of diffusion combustion of the round hydrogen microjets with different nozzle diameter. The new phenomenon is revealed during combustion of a hydrogen microjet, which we have named «bottleneck». The special attention has been given to research of characteristics of the «bottleneck» development and its role during of a hydrogen round microjet combustion. It is shown, that «bottleneck» represents the closed spherical area of the hydrogen with air mixture combustion in a jet near-field. The «bottleneck» area is closed by a powerful density gradient. It is found, that the laminar hydrogen jet in this area overcomes a density gradient of gas, becomes turbulent and combustion process is accompanied both a turbulent jet, and a turbulent flame further downstream evolution. It is shown, that the spatial size of a «bottleneck» decreases with growth of a jet velocity.

Keywords:
round hydrogen microjet, hydrogen diffusion combustion, schlieren method, shadow patterns. 
УДК 544.452.42

DIFFERENT CONDITIONS OF THE ROUND HYDROGEN JETS DIFFUSION COMBUSTION IN AIR