Near-field Blast Wave Characteristics of Spherical and Cylindrical Charges

doi:10.12382/bgxb.2023.1105

Abstract

Abstract:

The near-field blast wave characteristics(0.06m/kg^1/3<Z<1m/kg^1/3)of typical charge structures(sphere and cylinder)are investigated for supporting the protection of sympathetic detonation through near-field explosion experiment and numerical simulation.The load of near-field blast wave of cylindrical charge is experimentaly investigated,and a numerical caculation model of near-field explosion is established,The near-field blast wave structures and spatial distributions for peak parameters of spherical and cylindrical charges are analyzed.The results show that the near-field explosion loads are affected by the detonation products,and the reflected overpressure histories exhibit multi-peak and jagged form,which are due to the effects of multiple reflection waves and the complex flow of detonation products after the Mach region.The inverse of pressure and density gradient between detonation products and shock wave interface leads to the Rayleigh-Taylor instability effect.The generated interfacial microjets of detonation products promote the complexity of multiple reflection wave structure,resulting in large uncertainty of measured results of near-field reflected loads.The near-field incident overpressure curve shows a typical double-peak structure,which comes from the air shock wave and detonation products.Due to the structural effects of charge,the incident wave loads of cylindrical charge distribute non-uniformly along the axial and radial directions.The spatial distribution of incident parameters drastically varies when the azimuth angle is between 30°-60° because of the bridging wave effects.The modified predictive model can capture the incident peak overpressure and impulse in the range of 0.06m/kg^1/3<Z<1m/kg^1/3 for cylindrical charge(L/D=0.8)with center initiation under arbitrary azimuth angle,and the relative deviations among predicted results and numerical results of incident peak overpressure and impulse are less than 20%.

Key words: spherical charges, cylindrical charges, near-field blast wave, structure effect, detonation product, predictive model

CLC Number:

O389

MA Ruilong, WANG Xinjie, SUN Zhimin, YOU Sa, HUANG Fenglei. Near-field Blast Wave Characteristics of Spherical and Cylindrical Charges[J]. Acta Armamentarii, 2025, 46(1): 231105-.

Figures/Tables 20

Fig.1 Layout of blast wave measurement site for near field explosion of cylindrical charge

Fig.2 Histories of blast wave pressure and impulse in near field explosion of cylindrical charge

Fig.3 Contribution of detonation products to reflected peak overpressure and impulse in near field explosion

Fig.4 Numerical simulation model of near field explosion for cylindrical and spherical charges

Table 1 Parameters of constitutive model for TNT[30]

ρ_0e/ (g·cm^-3)	D_C-J/ (m·s^-1)	p_C-J/ GPa	A/GPa	B/GPa
1.63	6900	21	371.2	3.21
R₁	R₂	ω	E₀/GPa
4.15	0.95	0.3	7.0

Table 2 Parameters of constitutive model for air[9]

ρ_0a/ (kg·m^-3)	p_0a/kPa	A₀~A₃	A₄	A₅	A₆
1.225	101.36	0	0.4	0.4	0

Table 3 Parameters of constitutive model for 45# steel[32]

ρ_0s/ (g·cm^-3)	E_e/GPa	υ	A/GPa	B/GPa	C
7.86	210	0.3	0.507	0.320	0.064
n	m	T_m/K	C₀/(m/s)	s	γ₀
0.28	1.06	1763	4250	1.61	1.75

Fig.5 Comparison of incident overpressures and impulses of cylindrical charges with different mesh sizes

Fig.6 Comparison of simulated and predicted incident peak overpressures and impulses

Fig.7 Structure evolution of blast wave of cylindrical charge in near field explosion

Fig.8 Comparison of simulated and experimental results of blast parameters of cylindrical charge

Fig.9 Evolution of reflected peak overpressure with scaled distance during near field explosion ofcylindrical charge

Fig.10 Evolution of near-field blast wave structures of spherical and cylindrical charges[35-36]

Fig.11 Comparison of characteristic parameters of near-field explosions of spherical and cylindrical charges

Table 4 Spatial distributions of incident blast waves of spherical and cylindrical charges

参数	球形装药	柱形装药
入射峰值超压
入射峰值冲量

Fig.12 Spatial non-uniformities of incident peak overpressures and impulses of cylindrical and spherical charges

Table 5 Table Parameters of proportion factor for incident peak overpressure of cylindrical charge m/k g 1 / 3

0.6≤Z<0.1	α₀₀	α₀₁	α₁₁	α₂₀	α₂₁
	-26.45	0.40	792.80	-0.0011	-9.41
	α₂₂	α₃₀	α₃₁	α₃₂	α₃₃
	-6.33×10³	-1.14×10^-5	0.044	29.93	1.61×10⁴
0.1≤Z<0.5	α₀₀	α₀₁	α₁₁	α₂₀	α₂₁
	7.71	-0.16	-44.60	0.0016	0.27
	α₂₂	α₃₀	α₃₁	α₃₂	α₃₃
	118.17	-5.92×10^-6	7.50×10^-4	-0.55	-85.31
0.5≤Z<1	α₀₀	α₀₁	α₁₁	α₂₀	α₂₁
	6.71	-0.33	-3.34	0.0045	0.21
	α₂₂	α₃₀	α₃₁	α₃₂	α₃₃
	-2.07	-2.09×10^-5	-4.62×10^-4	-0.12	3.87

Table 6 Parameters of proportion factor for incident peak impulse of cylindrical charge m/k g 1 / 3

0.06≤ Z<0.1	β₀₀	β₀₁	β₁₁	β₂₀	β₂₁
	-3.26	0.11	123.79	-8.71×10^-4	-2.31
	β₂₂	β₃₀	β₃₁	β₃₂	β₃₃
	-926.67	9.06×10^-7	0.014	4.66	2.96×10³
0.1≤ Z<0.5	β₀₀	β₀₁	β₁₁	β₂₀	β₂₁
	3.05	-0.13	5.24	0.0019	0.13
	β₂₂	β₃₀	β₃₁	β₃₂	β₃₃
	-33.02	-6.68×10^-6	-0.0015	0.068	32.96
0.5≤ Z<1	β₀₀	β₀₁	β₁₁	β₂₀	β₂₁
	6.86	-0.058	-20.00	9.85×10^-4	0.048
	β₂₂	β₃₀	β₃₁	β₃₂	β₃₃
	21.67	-1.30×10^-5	0.0018	-0.17	-4.42

Fig.13 Comparison of predicted and numerical results of incident parameters of cylindrical charge[10,23]

Fig.14 Relative deviation between predicted and numerical results of spherical and cylindrical charges

References 38

[1]	HUANG S, CHEN H Y, ZHANG R, et al. Uncovering the fracture behavior of metallic cylindrical shells under internal explosive loadings via careful design of densely-arranged multi-point photon Doppler velocimetry measurements[J]. International Journal of Impact Engineering, 2023,180:104679.
[2]	DENG G Q, YU X. Numerical study on the case effect of a bomb air explosion[J]. Defence Technology, 2021, 17(4):1461-1470. doi: 10.1016/j.dt.2020.08.003
[3]	XIAO Y C, XIAO X D, FAN C Y, et al. Study of the sympathetic detonation reaction behavior of a fuze explosive train under the impact of blast fragments[J]. Journal of Mechanical Science and Technology, 2021, 35(6):2575-2584.
[4]	YANG T H, WANG C, LI T. Numerical simulation study of sympathetic detonation in stages[J]. Defence Technology, 2022, 18(8):1382-1393. doi: 10.1016/j.dt.2021.08.009
[5]	李兴隆, 吴奎先, 路中华, 等. 叠层复合装药殉爆安全性试验及数值模拟[J]. 含能材料, 2022, 30(3):204-213.
	LI X L, WU K X, LU Z H, et al. Sympathetic detonation test and simulation of laminated composite charge[J]. Chinese Journal of Energetic Materials, 2022, 30(3):204-213. (in Chinese)
[6]	LIU J Y, DONG Y X, AN X Y, et al. Reaction degree of composition B explosive with multi-layered compound structure protection subjected to detonation loading[J]. Defence Technology, 2021, 17(2):315-326. doi: 10.1016/j.dt.2020.02.004
[7]	KINGERY C N, BULMASH G. Airblast parameters from TNT spherical air burst and hemispherical surface burst[M]. Aberdeen Proving Ground,MD,US: US Army Armament and Development Center, Ballistic Research Laboratory,1984.
[8]	HYDE D. ConWep:conventional weapons effects(Application of TM 5-855-1)[R]. Vicksburg,MS, US: US Army Corps of Engineers,Waterways Experiment Station,1992.
[9]	SHIN J. Air-blast effects on civil structures[R]. Buffalo,NY, US: State University of New York at Buffalo, 2014.
[10]	KARLOS V, SOLOMOS G, LARCHER M. Analysis of blast parameters in the near-field for spherical free-air explosions[R]. Ispra, Italy: Joint Research Center, 2016.
[11]	LAVAYSSIERE M, LEFRANCOIS A, CRABOS B, et al. Toward improvements in pressure measurements for near free-field blast experiments[J]. Sensors, 2023, 23(12):5635.
[12]	WILLIAMS K, JOHNSON C E. Evaluating blast wave overpressure from non-spherical charges using time of arrival from high-speed video[J]. Propellants,Explosives,Pyrotechnics, 2023, 48(7):1-13.
[13]	ZHAO X H, WANG G H, FANG H Y, et al. Shock wave propagation characteristics of cylindrical charge and its aspect ratio effects on the damage of RC slabs[J]. Advances in Materials Science and Engineering, 2021,2020:1-20.
[14]	KNOCK C, DAVIES N. Blast waves from cylindrical charges[J]. Shock Waves, 2013, 23(4):337-343.
[15]	KNOCK C, DAVIES N, REEVES T. Predicting blast waves from the axial direction of a cylindrical charge[J]. Propellants,Explosives,Pyrotechnics, 2015, 40(2):169-179.
[16]	RIGBY S, TYAS A, CLARKE S, et al. Observations from preliminary experiments on spatial and temporal pressure measurements from near-field free air explosions[J]. International Journal of Protective Structures, 2015, 6(2):175-190.
[17]	RIGBY S E, KNIGHTON R, CLARKE S D, et al. Reflected near-field blast pressure measurements using high speed video[J]. Experimental Mechanics, 2020, 60(7):875-888.
[18]	杨军, 李焰, 张德志, 等. 光子多普勒测速仪与压杆相结合的冲击波反射压力测试技术[J]. 兵工学报, 2017, 38(7):1368-1374. doi: 10.3969/j.issn.1000-1093.2017.07.015
	YANG J, LI Y, ZHANG D Z, et al. Measuring technique of reflected blast wave pressure based on pressure bar and photonic doppler velocimeter[J]. Acta Armamentarii, 2017, 38(7):1368-1374. (in Chinese) doi: 10.3969/j.issn.1000-1093.2017.07.015
[19]	张德志, 李焰, 王旺, 等., 球形装药近距离爆炸正反射冲击波实验研究[J]. 兵工学报, 2009, 30(12):1663-1669.
	ZHANG D Z, LI Y, WANG D W, et al. Experiment investigations on normal reflected blast wave near the spherical explosive[J]. Acta Armamentarii, 2009, 30(12):1663-1669. (in Chinese)
[20]	BARR A D, RIGBY S E, CLARKE S D, et al. Temporally and spatially resolved reflected overpressure measurements in the extreme near field[J]. Sensors, 2023, 23(2):964.
[21]	FAN Y, CHEN L, LI Z, et al. Modeling the blast load induced by a close-in explosion considering cylindrical charge parameters[J]. Defence Technology, 2022,24:83-108.
[22]	GAO C, KONG X Z, FANG Q, et al. Numerical investigation on free air blast loads generated from center-initiated cylindrical charges with varied aspect ratio in arbitrary orientation[J]. Defence Technology, 2022, 18(9):1662-1678. doi: 10.1016/j.dt.2021.07.013
[23]	LIU J, GAO C Z, SUN Z Y, et al. On the estimation of near-field air blast peak overpressure from cylindrical charges[J]. International Journal of Protective Structures, 2023, 0(0):1-13.
[24]	刘军, 王政, 熊俊, 等. 圆柱形炸药空爆在近场空间的超压估算公式[J]. 北京理工大学学报, 2022, 42(9):918-927.
	LIU J, WANG Z, XIONG J, et al. A near-field Overpressure estimation equation of cylindrical charge explosive air blast[J]. Transactions of Beijing Institute of Technology, 2022, 42(9):918-927. (in Chinese)
[25]	段晓瑜, 崔庆忠, 郭学永, 等. 炸药在空气中爆炸冲击波的地面反射超压实验研究[J]. 兵工学报, 2016, 37(12):2277-2283. doi: 10.3969/j.issn.1000-1093.2016.12.013
	DUAN X Y, CUI Q Z, GUO X Y, et al. Experimental investigation of ground reflected overpressure of shock wave in air blast[J]. Acta Armamentarii, 2016, 37(12):2277-2283. (in Chinese)
[26]	SCHWER L, RIGBY S. Reflected secondary shocks:some observations using afterburning[C]//Proceedings of the 11st European LS-DYNA Conference.Salzburg, Austria: DYNAmore GmbH, 2017.
[27]	POWELL D A, GOGOSIAN D, SCHWER L. Mesh sensitivity of blast wave propagation[C]//Proceedings of the 15th International LS-DYNA Users Conference.Detroit,MI, US: Livermore Software Technology Corporation, 2018.
[28]	LANGRAN WHEELER C, RIGBY S E, CLARKE S D, et al. Near-field spatial and temporal blast pressure distributions from non-spherical charges:horizontally-aligned cylinders[J]. International Journal of Protective Structures, 2021, 12(4):492-516.
[29]	LEE E L, HORING H C, KURY J W. Adiabatic expansion of high explosive detonation products,UCRL-50422[R]. Livermore,CA, US: Lawrence Radiation Laboratory,1968.
[30]	DOBRATZ B M. LLNL explosives handbook:properties of chemical explosives and explosives and explosive simulants[R]. Livermore,CA, US: Lawrence Livermore National Lab,1981.
[31]	JOHNSON G R, COOK W H. Fracture characteristics of three metals subjected to various strains,strain rates,temperatures and pressures[J]. Engineering Fracture Mechanics, 1985, 21(1):31-48.
[32]	陈刚, 陈忠富, 陶俊林, 等. 45号钢动态塑性本构参量与验证[J]. 爆炸与冲击, 2005, 25(5):451-456.
	CHEN G, CHEN Z F, TAO J L, et al. Investigatio and validation on plastic constitutive parameters of 45# stell[J]. Explosion and Shock Waves, 2005, 25(5):451-456. (in Chinese)
[33]	SHI Y C, LI Z X, HAO H. Mesh size effect in numerical simulation of blast wave propagation and interaction with structures[J]. Transactions of Tianjin University, 2008, 14(6):396-402.
[34]	KINNEY G, GRAHAM K. Explosive shocks in air[M]. Berlin, Germany:Springer,1985.
[35]	TYAS A, REAY J, WARREN J A, et al. Experimental studies of blast wave development and target loading from near-field spherical PETN explosive charges[C]//Proceedings of the 16th International Symposium for the Interaction of the Effects of Munitions with Structures.Miramar,FL, US: The University of Florida, 2015.
[36]	EGELN A A, HEWSON J C, GUILDENBECHER D R, et al. Post-detonation fireball modeling:Validation of freeze out approximations[J]. Physics of Fluids, 2023, 35(6):1-13.
[37]	NEEDHAM C E. Blast waves[M].Berlin, Germany:Springer, 2010.
[38]	PANNELL J J, PANOUTSOS G, COOKE S B, et al. Predicting specific impulse distributions for spherical explosives in the extreme near-field using a Gaussian function[J]. International Journal of Protective Structures, 2021, 12(4):437-459.