Effect of Inner Bore Structure of a Large-caliber Gun on the Inner Wall Loadings of Barrel during Engraving Process

doi:10.12382/bgxb.2024.0646

Abstract

Abstract:

During the engraving stage of projectile, the inner bore of gun barrel is in a harsh environment of high temperature, high pressure, rapid compression and friction. A severe wear at the beginning of rifling is caused by the large loadings on the inner wall of barrel during engraving process. The influences of different inner bore structures on the inner wall of barrel are studied using a large-caliber shallow rifling barrel as the object. The constitutive relationship of the rotating band material under high temperature and high strain rate is constructed through split Hopkinson pressure bar experiment, and the plastic deformation of rotating band, the engraving resistance, and the variation of loadings on the inner wall of barrel during the engraving process are analyzed using a finite element method. And the three-dimensional thermo-mechanical coupling engraving finite element models are established considering different bore structures such as rifling width, rifling cross-sectional shape, and forcing cone taper. The influences of different bore structures on inner wall loadings of barrel during the engraving process are calculated. The research results indicate that, for this type of gun, both the forcing cone structures and rifling structure have a significant impact on the loadings on the inner wall. Firstly, the increase in the forcing cone taper can lead to an increase in the engraving resistance and the loadings on the inner wall of barrel, and the ending time of engraving process and the peak times of the engraving resistance and the loadings on the inner wall of barrel are also advanced. Secondly, the peak loadings on the inner wall of barrel significantly increase with the width of land. But the top of the driving side can be changed to effectively reduce the loadings on the inner wall of barrel. The peak value of the loadings on the inner wall of barrel is decreased by 9.87% after rounding and 5.59% after chamfering. This study contributes to enriching the design methods of bore structures based on the lifespan of the barrel.

Key words: large-caliber gun, engraving of rotating band, dynamic mechanical property, loadings on inner wall of barrel, bore structure

CLC Number:

TJ301

LI Yifan, FU Jiawei, YANG Diao, LI Yanze. Effect of Inner Bore Structure of a Large-caliber Gun on the Inner Wall Loadings of Barrel during Engraving Process[J]. Acta Armamentarii, 2024, 45(11): 4106-4118.

Figures/Tables 29

Fig.1 SHPB experimental system

Fig.2 Loaded rotating band specimen

Fig.3 The original experimental waveforms

Fig.4 Dynamic compressive stress-strain test results at different temperatures

Fig.5 Dynamic compressive stress-strain curves under different strain rates

Fig.6 Temperature softening effect of rotating band materials (equivalent plastic strain of 0.015)

Fig.7 Strain rate strengthening effect of rotating band material (equivalent plastic strain of 0.015)

Table 1 Johnson-Cook constitutive parameters of rotating band material

A/MPa	B/MPa	n	C	m
126.66	774.21	0.72	0.007	1.33

Fig.8 Comparison between J-C model forecast result and experimental data

Fig.9 Relationship between strain rate strengthening coefficient C and temperature

Fig.10 Comparison between revised J-C model forecast result and experimental data

Fig.11 Schematic diagram of the forces on the barrel during engraving process

Table 2 Finite element model material parameters

部件	密度/(kg·m^-3)	杨氏模量/GPa	泊松比
身管	7800	210	0.25
弹体	6000	206	0.27
弹带	8930	116	0.33

Fig.12 Finite element mesh models of projectile and barrel

Fig.13 Von Mises stress nephogram of rotating band

Fig.14 Variation of engrave resistance with time

Fig.15 Variation of loadings on inner wall of barrel with time

Fig.16 Variation of peak loadings on inner wall with land width

Fig.17 Rifling structures with different cross-sectional shapes

Fig.18 Variation of engraving resistance with time under different fillet sizes

Fig.19 Variation of loadings on inner wall of barrel with time under different fillet sizes

Fig.20 Variation of engraving resistance with time under different chamfer sizes

Fig.21 Variation of loadings on inner wall of barrel with time under different chamfer sizes

Fig.22 Forcing cone structure of a large-caliber gun

Fig.23 Bayonet chamber positions of projectile under different forcing cone tapers

Fig.24 Variation of engraving resistance with time under different forcing cone tapers

Fig.25 Variation of loadings on inner wall of barrel with time under different forcing cone tapers

Fig.26 Variation of powder gas pressure with time under different forcing cone tapers

Table 3 The effect of forcing cone taper on engraving parameters

K	l/ mm	t/ ms	t₁/ ms	F_m/ kN	σ_m/ MPa	v /(m·s^-1)	p/ MPa
1/10	41	3.95	2.8	1198.08	694.31	88.19	204.97
1/9	37.08	3.87	2.71	1236.19	718.51	89.84	209.44
1/8	32.96	3.8	2.68	1249.28	725.64	91.45	220.33
1/7	28.84	3.64	2.56	1254.4	735.06	89.47	223.91
1/6	24.72	3.43	2.48	1264.19	735.82	88.14	226.55
1/5	20.6	3.15	2.34	1274.31	740.86	87.86	232.33

References 33

[1]	JOHNSON G R, COOK W H. A constitutive model and data for metals subjected to large strains, high strain rates and high temperatures[C]// Proceedings of the 7th International Symposium on Ballistics. Hague, the Netherlands: IBC, 1983: 541-547.
[2]	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.
[3]	KHAN A S, HUANG S. Experimental and theoretical study of mechanical behavior of 1100 aluminum in the strain rate range 10^-5-10⁴s^-1[J]. International Journal of Plasticity, 1992, 8(4): 397-424.
[4]	KHAN A S, LIANG R. Behaviors of three BCC metal over a wide range of strain rates and temperatures: experiments and modeling[J]. International Journal of Plasticity, 1999, 15(10): 1089-1109.
[5]	STEINBERG D J, COCHRAN S G, GUINAN M W. A constitutive model for metals applicable at high-strain rate[J]. Journal of Applied Physics, 1980, 51(3): 1498-1504.
[6]	STEINBERG D J, LUND C M. A constitutive model for strain rates from 10^-4 to 10⁶s^-1[J]. Journal of Applied Physics, 1989, 65(4): 1528-1533.
[7]	李淼. 弹丸膛内起始运动过程瞬态特性研究[D]. 南京: 南京理工大学, 2017: 39-55.
	LI M. Dynamic characteristics study of the projectile initial motion in bore[D]. Nanjing: Nanjing University of Science and Technology, 2017: 39-55. (in Chinese)
[8]	ZHU Y C, FU J W, QIAN L F, et al. A phenomenological model for plastic flow behavior of rotating band material with a large temperature range[J]. Defence Technology, 2023, 25: 121-133.
[9]	CHEN P C T. Analysis of engraving and wear in a projectile rotating band, ARCCB-TR-99012[R]. Watervliet, NY, US: U.S. Armament Research, Development and Engineering Center, 1999.
[10]	CHEN P C T, LEACH M. Modeling of barrel/projectile interaction in a rotating band, ARCCB-TR-01011[R]. Watervliet, NY, US: U.S. Armament Research, Development and Engineering Center, 1999.
[11]	SOUTH J, POWERS B, MINNICINO M. Evaluations of computational techniques for the engraving of projectiles[J]. WIT Transactions on Modelling and Simulation, 2007, 45: 193-202.
[12]	KEINÄNEN H, MOILANEN S, TERVOKOSKI J, et al. Influence of rotating band construction on gun tube loading—part Ⅰ: numerical approach[J]. Journal of Pressure Vessel Technology-Transactions of the ASME, 2012, 134(4): 041006.
[13]	TOIVOLA J, MOILANEN S, TERVOKOSKI J, et al. Influence of rotating band construction on gun tube loading—part Ⅱ: measurement and analysis[J]. Journal of Pressure Vessel Technology-Transactions of the ASME, 2012, 134(4): 041007.
[14]	孙全兆, 杨国来, 王鹏, 等. 某大口径榴弹炮弹带挤进过程数值模拟研究[J]. 兵工学报, 2015, 36(2): 206-213. doi: 10.3969/j.issn.1000-1093.2015.02.003
	SUN Q Z, YANG G L, WANG P, et al. Numerical research on rotating band engraving process of a large-caliber howitzer[J]. Acta Armamentarii, 2015, 36(2):206-213. (in Chinese)
[15]	程申申, 陶如意, 王浩, 等. 弹丸不同结构尼龙弹带挤进过程的阻力特性[J]. 兵工学报, 2021, 42(9):1847-1857.
	CHENG S S, TAO R Y, WANG H, et al. Dampling characteristics of projectile in engraving process of nylon sealing band[J]. Acta Armamentarii, 2021, 42(9):1847-1857. (in Chinese) doi: 10.3969/j.issn.1000-1093.2021.09.005
[16]	李淼, 钱林方, 孙河洋. 某大口径火炮弹带热力耦合挤进动力学数值模拟研究[J]. 兵工学报, 2016, 37(10): 1803-1811. doi: 10.3969/j.issn.1000-1093.2016.10.006
	LI M, QIAN L F, SUN H Y. Research on coupled thermo-mechanical model during rotating band engraving process[J]. Acta Armamentarii, 2016, 37(10): 1803-1811. (in Chinese) doi: 10.3969/j.issn.1000-1093.2016.10.006
[17]	邹利波, 于存贵, 冯广斌, 等. 基于温度修正的弹丸挤进身管过程摩擦模型[J]. 兵工学报, 2021, 42(6): 1148-1156. doi: 10.3969/j.issn.1000-1093.2021.06.004
	ZOU L B, YU C G, FENG G B, et al. Friction model of projectile engraving process based on temperature correction[J]. Acta Armamentarii, 2021, 42(6): 1148-1156. (in Chinese) doi: 10.3969/j.issn.1000-1093.2021.06.004
[18]	师军飞, 钱林方, 陈红彬, 等. 埋头弹高速冲击挤进入膛特性研究[J]. 兵工学报, 2023, 44(3): 656-669. doi: 10.2382/bgxb.2022.0834
	SHI J F, QIAN L F, CHEN H B, et al. High-speed impact engraving characteristics of cased telescoped ammunition[J]. Acta Armamentarii, 2023, 44(3): 656-669. (in Chinese) doi: 10.2382/bgxb.2022.0834
[19]	ZHANG S J, RUI X T, YU H L, et al. Numerical simulation of the coupled dynamics model of the projectile engraving process[J]. International Journal of Mechanical System Dynamics, 2024, 4(2): 188-201.
[20]	YANG M, YU Y G. Dynamic engraving characteristics of nylon belt under different charge conditions[J]. Journal of Mechanics, 2024, 40: 155-163.
[21]	GUO C Y, YANG G L, GE J L, et al. Effect of ramming initial state on band engraving in smooth-bore guns[C]// Journal of Physics: Conference Series. IOP Publishing, 2023, 2478(2): 022009.
[22]	陆野, 周克栋, 赫雷, 等. 坡膛结构参数对枪械内弹道挤进时期的影响研究[J]. 兵工学报, 2015, 36(7): 1363-1369. doi: 10.3969/j.issn.1000-1093.2015.07.028
	LU Y, ZHOU K D, HE L, et al. Influence of structure parameters of forcing cone on small arms interior ballistics during engraving[J]. Acta Armamentarii, 2015, 36(7): 1363-1369. (in Chinese) doi: 10.3969/j.issn.1000-1093.2015.07.028
[23]	张鑫, 于存贵, 牛志鹏, 等. 某大口径火炮身管坡膛结构优化设计[J]. 火炮发射与控制学报, 2021, 42(4): 74-80.
	ZHANG X, YU C G, NIU Z P, et al. Optimization design of chamber structure of a large-caliber gun barrel[J]. Journal of Gun Launch & Control, 2021, 42(4): 74-80. (in Chinese)
[24]	王少泉, 李强, 樊江涛, 等. 某小口径火炮弹丸挤进过程动力学特性分析[J]. 振动与冲击, 2024, 43(12): 241-247.
	WANG S Q, LI Q, FAN J T, et al. Analysis of the dynamic characteristics of a small caliber gun's bullet engraving process[J]. Journal of Vibration and Shock, 2024, 43(12): 241-247. (in Chinese)
[25]	许耀峰, 丁宏民, 徐坚, 等. 大口径火炮膛线结构对滑动弹带弹丸膛内运动影响的数值分析[J]. 兵工学报, 2016, 37(11): 2148-2156. doi: 10.3969/j.issn.1000-1093.2016.11.024
	XU Y F, DING H M, XU J, et al. Numerical analysis of influence of rifling structure of large caliber gun on moving of projectile with sliding driving band in bore[J]. Acta Armamentarii, 2016, 37(11): 2148-2156. (in Chinese)
[26]	杨峰, 张健, 郭策安. 一种新型结构火炮身管膛线的计算分析[J]. 计算力学学报, 2020, 37(6): 729-734.
	YANG F, ZHANG J, GUO C A. Force calculation and analysis of a new gun barrel rifle[J]. Chinese Journal of Computational Mechanics, 2020, 37(6): 729-734. (in Chinese)
[27]	张鑫, 梁林, 邹利波, 等. 某大口径火炮身管膛线结构优化设计[J]. 火炮发射与控制学报, 2021, 42(2): 62-67, 83.
	ZHANG X, LIANG L, ZOU L B, et al. Optimization design of rifling structure of a certain large-caliber gun barrel[J]. Journal of Gun Launch & Control, 2021, 42(2): 62-67, 83. (in Chinese)
[28]	郭俊行, 刘琦, 丁宏民, 等. 基于光滑粒子法的某大口径火炮不同膛线弹丸挤进过程研究[J]. 振动与冲击, 2021, 40(24): 75-81.
	GUO J H, LIU Q, DING H M, et al. A study on rotating band engraving process for large caliber gun projectile with different rifles[J]. Journal of Vibration and Shock, 2021, 40(24): 75-81. (in Chinese)
[29]	卢芳云, 陈荣, 林玉亮, 等. 霍普金森杆实验技术[M]. 北京: 科学出版社, 2013: 30-32.
	LU F Y, CHEN R, LIN Y L, et al. Hopkinson bar techniques[M]. Beijing: Science Press, 2013: 30-32. (in Chinese)
[30]	STIFFLER A K. Friction of plastic rotating bands, AD-A150666[R]. Eglin Air Force Base, FL, US: Air Force Armament Laboratory,1984.
[31]	周彦煌, 王升晨. 实用两相流内弹道学[M]. 北京: 兵器工业出版社, 1990.
	ZHOU Y H, WANG S C. Practical two-phase flow interior ballistics[M]. Beijing: Publishing House of Ordnance Industry, 1990. (in Chinese)
[32]	张相炎, 郑建国, 袁人枢. 火炮设计理论[M]. 北京: 北京理工大学出版社, 2014: 21-27.
	ZHANG X Y, ZHENG J G, YUAN R S. Theory of gun design[M]. Beijing: Beijing Institute of Technology Press, 2014: 21-27. (in Chinese)
[33]	李淼, 钱林方, 陈龙淼. 弹带挤进过程内弹道特性研究[J]. 振动与冲击, 2016, 35(23): 74-79.
	LI M, QIAN L F, CHEN L M. Interior ballistics’ features during rotating band engraving process[J]. Journal of Vibration and Shock, 2016, 35(23): 74-79. (in Chinese)