Abstract:
Impinging jet injectors has often been a preferred con-figuration in liquid propellant rockets, the most common form of which is the Liquid-on-Liquid doublet. This config-uration provides numerous advantages that it can be pro-posed as an alternative to coaxial injectors for engines em-ploying gas-liquid propellants. Efforts to achieve this re-sults in Gas-on-Liquid impinging injectors employing iden-tical orifices. Nevertheless a problem identified with it tha t it could not give desired mass distribution for a given mass ratio (MR). This problem could be corrected by using vari-able gas orifices. In the present work the effect of employ-ing variable gas orifices is investigated. It has been found that at low MR the SMD (Sauter mean diameter) obtained by using variable gas orifices are comparable and at high MR the small orifice yields low SMD. For the MR used for cryogenic application the large orifice require only low pressure budget rendering it a suitable choice.