Numerical study on powder fuel injection characteristics of powder fuel scramjet

• Published in: Powder technology Vol. 399; p. 117169
• Main Authors: Ding, Hong-ming, Zhuo, Chang-fei, Chen, Xiong, Deng, Hang-yu
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.02.2022; Elsevier BV
• Subjects: Acceleration; Aluminum; CFD-DEM method; Computational fluid dynamics; Computer applications; Convection; Convergence; Discrete element method; Drag; Flow simulation; Fluid dynamics; Fuel injection; Hydrodynamics; Injection; Mathematical models; Multiphase flows; Nozzles; Particle collisions; Particle flows; Powder; Supersonic combustion ramjet engines; Supersonic flows; Velocity; Multiphase flows; Drag; Supersonic flows; Particle flows; CFD-DEM method
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2022.117169

Powder fuel injection is an attractive technique for powder fuel scramjets and plays an important role in numerically investigating the particle velocity and concentration distribution in powder fuel injection. In this study, the coupled model of computational fluid dynamics-discrete element method (CFD-DEM) was used to simulate the flow of aluminium powder in the nozzle. Firstly, the flow field characteristics of gas-phase and two-phase gas-particle were compared. The results show that the particle disturbance has a great influence on the convection field, in which the maximum velocity of gas-phase is reduced by 47.15%, the acceleration distance is shortened by 34.18%, and the minimum velocity is reduced by 41.48%. Secondly, particle velocity and concentration distributions under different nozzle convergence angles were compared, and their correlations with the nozzle convergence angle, particle collision, and gas-particle drag force were identified. The results show that as increase in convergence angle of the nozzle, both the number of particle collisions in the nozzle and expansion angle of the particle jet at the nozzle exit have increased, while the particle velocity at the nozzle exit has decreased. The overall simulation results and analyses provide a new reference for the flow mechanism of the fuel injection process and the design of a powder conveying system for a powder fuel scramjet. [Display omitted] •CFD-DEM approach used for compressible dense gas solid two-phase was verified.•The particle velocity decreases with the increase of nozzle convergence angle at nozzle exit.•The particle expansion angle increases with the increase of nozzle convergence angle.•Particle velocity is mainly affected by the number of particle collision inside nozzle.