Experimental and numerical investigations of the effect of charge density and scale on the heat transfer behavior of Al/CuO nano-thermite. (February 2021)

• Record Type: Journal Article
• Authors: Wang, Yueting; Dai, Ji; Xu, Jianbing; Shen, Yun; Wang, Cheng-ai; Ye, Yinghua; Shen, Ruiqi
• Is Part Of: Vacuum. Volume 184(2021)
• Publication Date: 2021-02
• Subjects: Energetic material -- Nano-thermites -- Micro-scale combustion -- Theoretical calculation; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2020.109878
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: In this paper, to study the propagation behavior and the burning rate enhancement of Al/CuO nano-thermite in confined burn tubes, modification of the component was achieved by introducing energetic binder nitrocellulose (NC). The combustion behavior of Al/CuO and Al/CuO@NC nano-thermites in burn tubes was contrastively investigated by turning the charge density and the tube diameter in the range of 0.8–1.8 g/cm 3 and 0.3–2 mm, respectively. Our experiments and theoretical calculation results show that the seepage of the gas flow is an important factor affecting the heat transfer process of Al/CuO nano-thermite in burn tubes, which makes the propagation velocity decrease with the increase of the charge density. Meanwhile, by introducing a certain amount of NC into the component, the reactivity can be improved while the gas production and pressurization capacity can be increased at the same time. This can greatly improve the propagation velocity of Al/CuO nano-thermite under constraint conditions. Moreover, with the decrease of the tube diameter, it can be inferred that the significant increase of the relative heat loss is the main reason for the decrease of the propagation velocity while the dimensionless parameter θ can be used to analyze the heat loss coefficient under different charge diameters. Highlights: The combustion behavior of Al/CuO in confined burn tubes were studied experimentally and theoretically. Efficient and rapid combustion of Al/CuO nano-thermite at 0.3 mm charge dimension was realized. More gas products can improve the efficiency of the energy transfer of Al/CuO in confined burn tubes. Surface to volume ratio is a critical parameter affecting the energy transfer efficiency of Al/CuO at micro charge scales.