The deposition of combustion products in powder-fueled ramjet will aggravate the ablation of thermal protection materials, change the internal structure and size of the engine, and seriously affect the engine performance. Therefore, the combustion and deposition characteristics of aluminum-based powder-fueled ramjet are investigated by ground direct connection test, and the micro-morphology and composition of deposition at different positions are analyzed. The results show that the deposition in the combustion chamber is mainly distributed in the nozzle contraction section and the secondary air inlet. With the increase of air-fuel ratio, the pressure fluctuation of combustion chamber decreases gradually, and the combustion efficiency of engine increases continuously, up to 95%. Increasing air-fuel ratio has little effect on the deposition distribution, but it can effectively reduce the deposition rate in the combustion chamber and improve the specific impulse efficiency. At the head of the combustion chamber, the deposit is granular, mainly composed of aluminum, and the deposit downstream of the secondary air inlet is block or strip, mainly composed of alumina, and there are two different crystal forms. There are several different deposition forms after the particles collide with the wall, such as keeping spherical, developing into liquid film, splashing, sliding along the wall, etc. In addition, due to the existence of oxide film, the collision between aluminum particles and the wall may cause the oxide film to rupture.
[1] 胡春波, 李超, 孙海俊, 等. 粉末燃料冲压发动机研究进展[J]. 固体火箭技术, 2017, 40(03): 269-276.
HU Chunbo, LI Chao, SUN Haijun, et al. A summary of powder?fueled ramjet[J]. Journal of Solid Rocket Technology, 2017, 40(03): 269-276 (in Chinese).
[2] Wei Dong , Yong Tang , Zhenkun Hu , et al. Zero-carbon combustion of aluminum powder fuel using an axial-tangential swirl burner[J]. Energy, 2025, 322: 135595.
[3] Shibin Luo , Yanbin Feng , Jiawen Song, et al. Progress and challenges in exploration of powder fueled ramjets[J]. Applied Thermal Engineering, 2022,213(0): 118776.
[4] Yingying Lu, Kai Ma , Changchao Guo , et al. Experimental Studies on Thermal Oxidation and Laser Ignition Properties of Al-Mg-Li[J]. Powders Materials, 2023,16(21): 6931.
[5] Cheng Zhang, Yong Kou, Lei Xiao, et al. Research Progress on the Modification of B and Al High-Energy Fuels for Powder Fuel Ramjet Applications[J].ACS Applied Materials & Interfaces, 2025,17(8): 11522-11551.
[6] Goroshin S, Higgins A, Kamel M. Powdered metals as fuel for hypersonic; ramjets[C]//37th Joint Propulsion Conference and Exhibit, Salt Lake City, Utah, AIAA 2001-3919.
[7] 申慧君, 夏智勋, 胡建新, 等. 粉末燃料冲压发动机理论性能分析[J]. 推进技术, 2007, 28(02): 181-185.
SHEN Huijun, XIA Zhixun, HU Jianxin, et al. Theoretical performance analysis of the powdered fuel ramjet[J]. Journal of Propulsion Technology, 2007, 28(02): 181-185 (in Chinese).
[8] 孔龙飞, 夏智勋, 胡建新, 等. 驻涡火焰稳定器式粉末燃料冲压发动机两相流数值模拟[J]. 固体火箭技术, 2013, 36(01): 32-36.
HU Chunbo, LI Chao, SUN Haijun, et al. A summary of powder?fueled ramjet[J]. Journal of Solid Rocket Technology, 2013, 36(01): 32-36. (in Chinese).
[9] 马利锋, 杨玉新, 霍东兴, 等. 大速差射流装置对固体粉末冲压发动机燃烧性能的影响分析[J]. 中国科学: 技术科学, 2015, 45(01): 21-24.
Ma Lifeng, Yang Yuexin, Huo Dongxing, et al. Analysis on the combustion performance resulted of the big speed difference combustion stabilization device in the solid power fuel ramjet[J]. Scientia Sinica Technologica, 2015, 45(01): 21-24 (in Chinese).
[10] Shimon S. Experimental investigation of metalized solid fuel ramjet combustor[J]. Journal of Energetic Materials and Chemical Propulsion, 2012, 11(2): 107-121.
[11] Zuodong Liang, Ming Jiang , Ronggang Wei, et al. Combustion Performance and Deposit Characteristics of Boron-Aluminum Composite Fuel in a Powder-Fueled Ramjet: A Ground Test Study[J].Molecules, 2025, 30(7):1503.
[12] 申慧君, 夏智勋, 胡建新, 等. 金属粉末燃料冲压发动机初步试验研究[J]. 固体火箭技术, 2008, 31(3): 225-227+231.
SHEN Huijun, XIA Zhixun, HU Jianxin, et al. Preliminary experimental investigation on metal-powder fuel ramjet[J]. Journal of Solid Rocket Technology, 2008, 31(3): 225-227+231 (in Chinese).
[13] Xia Z, Shen H, Hu J, et al. Experimental investigation of powdered metals fuel ramjet[C], AIAA/ASME/SAE/ASEE, Joint Propulsion Conference & Exhibit. 2008.
[14] Chao L, Hu C, Xin X, et al. Experimental study on the operation characteristics of aluminum powder fueled ramjet[J]. Acta Astronautica, 2016, 129(0): 74-81.
[15] Yihua Xu , Rui Jia , Humberto Medina, et al. Effect of tangential swirl air inlet angle on the combustion efficiency of a hybrid powder-solid ramjet[J]. Acta Astronautica, 2019, 159(0): 87-95.
[16] Wenxiong Xi , Jian Liu , Ren Mengfei, et al. Improvement of Mixing Efficiency in the Combustion Chamber of a Powder-Fuel Ramjet Engine [J].Frontiers in Energy Research, 2021,9,756905.
[17] Dequan Xu , Shibin Luo , Miao Yang , et al. Inlet layout effects on the mixing performance with a novel mixing evaluation in a powder-fueled ramjet[J]. Fuel, 2022, 327: 125145.
[18] Shibin Luo , Dequan Xu , Jun Liu ,et al. Improvement of combustion performance with novel vortex generators in the powder-fueled ramjets[J].Aerospace Science and Technology, 2023, 172: 108598.
[19] Peihui X, Xingang D, Wenke Z, et al. Effect of AP coating or blending on the ignition and combustion of Al particles under a high-pressure water vapour-Ar environment[J]. Combustion and Flame, 2024, 263: 113382
[20] Sherif E, Ali S, Ahmed M, et al. The concealed role of reactive metal passive oxide layer: novel activated aluminum particles, combustion, kinetics, and ballistic performance[J]. Journal of Thermal Analysis and Calorimetry, 2025, 150(7): 5123-5132.
[21] 关轶文. 高温氧化铝沉积条件下绝热层烧蚀机理研究[D]. 西安:西北工业大学, 2019.
GUAN Yiwen. Research on Ablation Mechanism of Insulator Under High Temperature Alumina Deposition Condition[D]. Northwestern Polytechnical University, 2019 (in Chinese).
[22] 雷宁,熊唯. 国外固体火箭发动机铝熔渣机理研究[J]. 飞航导弹, 2019, 2: 89-94.
LEI Ning, XIONG Wei. Research on the mechanism of aluminum slag in solid rocket motors abroad[J]. Aerodynamic Missile Journal, 2019, 2: 89-94 (in Chinese).
[23] 孔龙飞. 驻涡式粉末燃料冲压发动机燃烧组织技术研究[D]. 国防科学技术大学, 2012.
KONG Longfei. Investigations on Combustion Organization Technology of Trapped Vortex Powdered Fuel Ramjet[D]. National University of Defense Technology, 2012 (in Chinese).
[24] Xu Wang , Yanpeng Bu , Xu Xu , et al. Experimental investigation on the thrust regulation of a Mg-CO2 Martian ramjet[J]. Acta Astronautica, 2022, 197: 191-199.
[25] Qingchun Yang , Xu Wang , Xu Xu , et al. Effects of magnesium particle size on combustion characteristic of martian ramjet engine[J]. Energy, 2022, 260: 125121.
[26] Xu WANG , Yanpeng BU , Xu XU , et al. Effect of mixing section configurations on combustion efficiency of Mg-CO2 Martian ramjet[J]. Chinese Journal of Aeronautics, 2022, 36(4): 165-173.
[27] Shixuan Hui, Hui Qi, Dianlong Sun, et al. Numerical study on multiphase combustion characteristics of aluminum-based powder-fueled water ramjet engine[J]. Chinese Journal of Aeronautics, 2024, 38(3): 103273.
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