A Comparison of the Performance of Uni-element Injectors for Laboratory Scale Gas-Liquid Rocket Engines

摘要

A quantitative study of the atomization of injector sprays is required to accurately predict and improve the performance characteristics of liquid propellant rocket engines. A laboratory scale setup of a Gas-Liquid Rocket Engine (GLRE) was designed to characterize the properties of a class of new fuels synthesized by the Defense Research and Development Laboratory, Hyderabad. An efficient atomization system was required for accurately predicting the I_(sp) values. Four injectors were designed and fabricated based on available literature. A preliminary spray characterization of the injectors under atmospheric conditions was conducted to analyse the trends of the Sauter Mean Diameter (SMD) with the radial and axial positions. The swirl coaxial injector was selected as the most suited design for the current engine design owing to its small breakup length, good atomization and good mixing. The shear coaxial injector provided better atomization but with a larger breakup length and higher velocities.