基于大涡模拟气固两相数值模型，本文对超声速流场内粉末燃料的掺混特性开展了详细研究。研究表明颗粒在超声速流场的流动行为具有显著的尺寸依赖性，在分布粒径条件下，较小颗粒会附着壁面并进入凹腔，较大颗粒则更接近主流区。进入凹腔前缘的颗粒驻留时间（约1 ms）显著长于绕过凹腔的颗粒（约0.4 ms）。对于2 μm和5 μm颗粒，其运动轨迹覆盖凹腔内低速回流区，通过再循环机制延长驻留时间。小尺寸颗粒（2 μm、5 μm）会引发剪切层轮廓的显著脉动，且更易受流场涡结构影响：其质量分数在喷射点附近达到约0.9，但向下游快速减小；主流区质量分数分布呈现明显不连续性（通常为0.1-0.3），且分布宽度大于大尺寸颗粒。相比之下，大尺寸颗粒（20 μm、40 μm）形成的剪切层轮廓更为平滑。增加喷射速度虽能略微提升颗粒射流穿透深度，但对总体颗粒驻留时间影响甚微。提高来流马赫数会缩短颗粒驻留时间，同时使颗粒射流发生偏转，促使更多颗粒进入凹腔。
Based on a large eddy simulation (LES) gas-solid two-phase numerical model, this paper conducts a detailed investigation of the mixing characteristics of powder fuel in a supersonic flow field. The study reveals that the flow behavior of particles in the supersonic flow field exhibits significant size dependency. Under distributed particle size conditions, smaller particles tend to adhere to the wall and enter the cavity, while larger particles remain closer to the mainstream region. The residence time of particles entering the leading edge of the cavity (approximately 1 ms) is significantly longer than that of particles bypassing the cavity (approximately 0.4 ms). For 2 μm and 5 μm particles, their trajectories cover the low-speed recirculation zone within the cavity, extending the residence time through a recirculation mechanism. Small-sized particles (2 μm, 5 μm) cause significant fluctuations in the shear layer profile and are more susceptible to the flow field vortex structures: their mass fraction reaches about 0.9 near the injection point but decreases rapidly downstream; the mass fraction distribution in the mainstream region shows obvious discontinuity (typically 0.1–0.3), with a wider distribution compared to larger particles. In contrast, larger particles (20 μm, 40 μm) form a smoother shear layer profile. Increasing the injection velocity slightly enhances the penetration depth of the particle jet but has minimal impact on the overall particle residence time. Increasing the incoming Mach number reduces the particle residence time and causes deflection of the particle jet, driving more particles into the cavity.
[1] 刘小勇, 王明福, 刘建文, 等. 超燃冲压发动机研究回顾与展望[J]. 航空学报, 2024, 45(05):226-252.
LIU X Y, WANG M F, LIU J W, et al. Review and pro-spect of research on scramjet[J]. Acta Aeronautica et Astronautica Sinica, 2024, 45(5):226-252 (in Chinese).
[2] 夏智勋, 冯运超, 马立坤, 等. 固体火箭超燃冲压发动机燃烧技术研究进展[J]. 航空学报, 2023, 44(15):82-96.
XIA Z X, FENG Y C, MA L K, et al. Research progress of solid rocket scramjet combustion technology[J]. Acta Aeronautica et Astronautica Sinica, 2023, 44(15):82-96 (in Chinese).
[3] RRE G, SUN H, HU C, et al. Historical trajectory, cur-rent status, and future challenges of powder engines and propellant supply technologies: A comprehensive re-view[J]. Defence Technology, 2025(published online).
[4] LUO S, FENG Y, SONG J, et al. Progress and challeng-es in exploration of powder fueled ramjets[J]. Applied Thermal Engineering, 2022, 213: 118776.
[5] DING H, ZHUO C, DENG H, et al. Experimental and numerical study on the development process and flow characteristics of powder fuel jet in the powder fuel scramjet[J]. Energy, 2023, 262: 125431.
[6] FENG Y, LUO S, SONG J, et al. Numerical investiga-tion on the combustion characteristics of aluminum powder fuel in a supersonic cavity-based combustor[J]. Applied Thermal Engineering, 2023(221), 119842.
[7] FENG Y, LUO S, SONG J, et al. Numerical investiga-tion on the combustion characteristics of powder fuel under different regulation parameters[J]. Aerospace Science and Technology, 2023(142), 108608.
[8] DUAN L, XIA Z, FENG Y, et al. Transient flameout process of boron-magnesium agglomerates during com-bustion in oxygen-rich atmospheres[J]. Particuology, 2024, 88: 290-301.
[9] LUO S, XU D, LIU J, et al. Improvement of combustion performance with novel vortex generators in the pow-der-fueled ramjets[J]. Aerospace Science and Technol-ogy, 2023, 142: 108598.
[10] MAIKAP S, R A K. Investigation of mixing character-istics and flow physics induced by spanwise tandem in-jection in supersonic crossflow[J]. Physical Review Fluids, 2024, 9(9): 093401.
[11] LI C, MA L, XIA Z, et al. Numerical investigation on mixing process of a sonic fuel jet into a supersonic crossflow[J]. International Journal of Hydrogen Energy, 2022, 47(87): 37025-37039.
[12] ZHAO M, BIAN Y, LI Q, et al. Large eddy simulation of transverse single/double jet in supersonic cross-flow[J]. Aerospace Science and Technology, 2019, 89: 31-45.
[13] WATANABE J, KOUCHI T, TAKITA K, et al. Large-eddy simulation of jet in supersonic crossflow with dif-ferent injectant species[J]. AIAA journal, 2012, 50(12): 2765-2778.
[14] WATANABE J, KOUCHI T, TAKITA K, et al. Charac-teristics of hydrogen jets in supersonic crossflow: large-eddy simulation study[J]. Journal of Propulsion and Power, 2013, 29(3): 661-674.
[15] SEBASTIAN R, SCHREYER A M. Design considera-tions for efficient spanwise-inclined air-jet vortex gen-erators for separation control in supersonic and hyper-sonic flows[J]. Aerospace Science and Technology, 2024, 147: 109033.
[16] ZHAO K, XIA Z, MA L, et al. Large-eddy simulation of gas-particle two-phase jet into a supersonic crossflow[J]. Physics of Fluids, 2023, 35(2).
[17] LI X, ZHANG H, BAI B. Particle-free zone of the two phase flow in a convergent-divergent nozzle[J]. Powder Technology, 2021, 394:1169-1177.
[18] YU H, YANG S, HU J, et al. Numerical investigation of wide continuous particle size distribution on the super-sonic powder loading oxygen jet[J]. Powder Technolo-gy, 2023, 428: 118885.
[19] BALAKRISHNAN K, BELLAN J. High-fidelity model-ing and numerical simulation of cratering induced by the interaction of a supersonic jet with a granular bed of solid particles[J]. International Journal of Multiphase Flow, 2018, 99: 1-29.
[20] LI C, CHE Y, LEI R, et al. Study on the mixing charac-teristics of powder fuel in supersonic flow[J]. Acta As-tronautica, 2025,234:398-409.
[21] LOTH E, TYLER DASPIT J, JEONG M, et al. Super-sonic and hypersonic drag coefficients for a sphere[J]. AIAA journal, 2021, 59(8): 3261-3274.
[22] ZHANG Q, WEI Z, SU W, et al. Theoretical modeling and numerical study for thrust-oscillation characteris-tics in solid rocket motors[J]. Journal of Propulsion and Power, 2012, 28(2): 312-322
CJA