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Blast wave characteristics of multi-layer composite charge:Theoretical analysis,numerical simulation,and experimental validation

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Defence Technology（防务技术） 2023年第1期19卷 91-102页

作者： Jun-bao li wei-bing li Xiao-wen Hong Jia-xin Yu Jian-jun Zhu ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing210094China Inner Mongolia Metal Material Research Institute Yantai264003China China Ship Development and Design Center Wuhan 430064China

This article investigates the characteristics of shock wave overpressure generated by multi-layer composite charge under different detonation modes.Combining dimensional analysis and the explosion mechanism of the charge,a peak overpressure prediction model for the composite charge under singlepoint detonation and simultaneous detonation was established.The effects of the charge structure and initiation method on the overpressure field characteristics were investigated in AUTODYN simulation.The accuracy of the prediction model and the reliability of the numerical simulation method were subsequently verified in a series of static explosion experiments.The results reveal that the mass of the inner charge was the key factor determining the peak overpressure of the composite charge under single-point detonation.The peak overpressure in the radial direction improved apparently with an increase in the aspect ratio of the charge.The overpressure curves in the axial direction exhibited a multi-peak phenomenon,and the secondary peak overpressure even exceeded the primary peak at distances of 30D and 40D(where D is the charge diameter).The difference in peak overpressure among azimuth angles of 0-90°gradually decreased with an increase in the propagation distance of the shock wave.The coupled effect of the detonation energy of the inner and outer charge under simultaneous detonation improved the overpressure in both radial and axial directions.The difference in peak overpressure obtained from model prediction and experimental measurements was less than 16.4%.

关键词： Blast wave characteristics Multi-layer composite charge Dimensional analysis AUTODYN mapping Model Explosion experiment

Numerical simulation of the blast wave of a multilayer composite charge

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Defence Technology（防务技术） 2020年第1期16卷 96-106页

作者： Xiao-wen Hong wei-bing li wei Cheng Wen-bin li He-yang Xu ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjingPR China Chongqing Hongyu Precision Industrial Co. LtdChongqingPR China

The numerical simulation of a blast wave of a multilayer composite charge is investigated.A calculation model of the near-field explosion and far-field propagation of the shock wave of a composite charge is established using the AUTODYN finite element program.Results of the near-field and far-field calculations of the shock wave respectively converge at cell sizes of 0.25-0.5 cm and 1-3 cm.The Euler--fluxcorrected transport solver is found to be suitable for the far-field calculation after mapping.A numerical simulation is conducted to study the formation,propagation,and interaction of the shock wave of the composite charge for different initiation modes.It is found that the initiation mode obviously affects the shock-wave waveform and pressure distribution of the composite charge.Additionally,it is found that the area of the overpressure distribution is greatest for internal and external simultaneous initiation,and the peak pressure of the shock wave exponentially decays,fitting the calculation formula of the peak overpressure attenuation under different initiation modes,which is obtained and verified by experiment.The difference between numerical and experimental results is less than 10%,and the peak overpressure of both internal and external initiation is 56.12% higher than that of central single-point initiation.

关键词： Structure of composite charge Initiation mode Blast wave Cell size in calculation Numerical simulation

Research on the intermediate phase of 40CrMnSiB steel shell under different heat treatments

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Defence Technology（防务技术） 2021年第3期17卷 1032-1041页

作者： wei-bing li Zhi-chuang Chen Xiao-ming Wang Wen-bin li ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing210094China

In this study, 40 Cr Mn Si B steel cylindrical shells were tempered at 350, 500 and 600 ℃ to study the effect of tempering temperature on the dynamic process of expansion and fracture of the metal shell. A midexplosion recovery experiment for the metal cylinder under internal explosive loading was designed, and the wreckage of the casings at the intermediate phase was obtained. The effects of different tempering temperatures on the macroscopic and microscopic fracture characteristics of 40 Cr Mn Si B steel were studied. The influence of tempering temperatures on the fracture characteristic parameters of the recovered wreckage were measured and analyzed, including the circumferential divide size, the thickness and the number of the circumferential divisions. The results show that as the tempering temperature was increased from 350 to 600 ℃, at first, the degree of fragmentation and the fracture characteristic parameters of the recovered wreckage changed significantly and then became essentially consistent. Scanning electron microscopy analysis revealed flow-like structure characteristics caused by adiabatic shear on different fracture surfaces. At the detonation initiation end of the casing, fracturing was formed by tearing along the crack, which existed a distance from the initiation end and propagated along the axis direction. In contrast, the fracturing near the middle position consists of a plurality of radial shear fracture units. The amount of alloy carbide that was precipitated during the tempering process increased continuously with tempering temperature, leading to an increasing number of spherical carbide particles scattered around the fracture surface.

关键词： Explosive mechanics Mid-explosion recovery experiment Explosion and fracture Heat treatment SEM(Scanning electron microscope)fracture analysis

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不同有机物料施用对菜地磷累积和转化的影响

环境科学 2024年第5期45卷 2871-2880页

作者：孙凯崔玉涛李顺晋魏冰丽王媛杨宏博王孝忠张伟西南大学资源环境学院重庆400715 西南大学长江经济带农业绿色发展研究中心重庆400715 西南大学农业科学研究院重庆400715 农业农村部西南山地农业绿色低碳重点实验室重庆400715

当前以土壤有机质提升为核心的耕地质量提升是保证粮食安全的基础,但在有机质提升过程中土壤磷素的累积和转化特征仍不清楚.在等碳施用条件下,研究对比不同有机物料投入对菜地不同土层土壤磷的累积、转化和迁移规律,以期同步实现有机质... 详细信息

当前以土壤有机质提升为核心的耕地质量提升是保证粮食安全的基础,但在有机质提升过程中土壤磷素的累积和转化特征仍不清楚.在等碳施用条件下,研究对比不同有机物料投入对菜地不同土层土壤磷的累积、转化和迁移规律,以期同步实现有机质提高和磷肥高效管理.试验设置对照(不施肥)、农户传统施肥、生物炭、鸡粪、餐厨废弃物和玉米秸秆施用这6个处理,于辣椒收获期测定各处理下不同土层有效磷(Olsen-P)和水溶性磷(CaCl_(2)-P)含量、土壤磷组分、有机质(SOM)和pH等指标.在0~5 cm和5~10 cm土层中,农户传统施肥处理有效磷含量最高,4种有机物料处理下有效磷顺序依次为:秸秆>生物炭>鸡粪>餐厨废弃物,秸秆和生物炭处理较餐厨废弃物分别增加59.6%~67.3%和29.1%~36.9%.秸秆处理最易于提升土壤活性磷库,0~5 cm土层土壤活性磷较鸡粪和餐厨废弃物处理分别增加47.3%和35.1%.随着土层深度增加鸡粪处理的有效磷降低比例最少,20~30 cm土层有效磷占表土层的55.9%,而在其他3种物料处理下仅占16.0%~34.0%.和农户传统施肥相比,有机物料施用后pH显著升高0.18~0.36个单位,鸡粪和餐厨废弃物处理的pH显著高于生物炭和秸秆(P<0.05).生物炭处理下SOM含量相比其他3种有机物料显著增加7.7%~17.6%.4种有机物料中,秸秆提高土壤活性磷库的效果最佳,有利于快速提升植物可利用磷;鸡粪处理下磷素最易向下迁移;在基于土壤地力提升的农田管理下,施用生物炭既有利于改善土壤酸碱度和提高SOM,也可避免磷素在耕层过量积累,降低环境风险.

关键词：有机物料磷组分有效磷(Olsen-P) pH 累积转化

Experimental study on explosion dispersion process of a multi-layer composite charge under different initiation modes

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Defence Technology（防务技术） 2020年第4期16卷 883-892页

作者： Xiao-wen Hong wei-bing li Wen-bin li He-yang Xu Bo-liang Wang wei Xiao ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjingPR China School of Chemical Engineering Nanjing University of Science and TechnologyNanjingPR China

The influe nce of initiation modes on the explosive dispersion process of the multi-layer co mposite charge(MCC) was studied.Overpressure sensors and high-speed photography system were used to investigate the energy release process of an MCC with a specific structure.The shock wave pressure and explosive dispersion characteristics of the MCC under different initiation modes were compared.The forming and expanding process of the shock wave of the composite charge under different initiation modes was determined.The separation position of the shock wave and fireball interface was determined.The calculation formulas of the shock radius and overpressure of the composite charge are presented.The radius of the shock wave of the composite charge was significantly affected by the initiation mode.Moreover,the development process of the composite explosive fireball under different initiation modes was analyzed,the variation rules of the composite charge dispersion radius and fireball dispersion velocity with time were obtained under the different initiation modes,the explosion energy release rate of composite charge under simultaneous initiation modes was the highest,and the peak overpressure under the simultaneous initiation mode was 1.61 times that of central single-point initiation.

关键词： Composite charge Initiation mode Blast wave Overpressure Dispersion radius

Fracture mechanism of a cylindrical shell cut by circumferential detonation collision

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Defence Technology（防务技术） 2021年第5期17卷 1650-1659页

作者： He-yang Xu wei-bing li Wen-bin li Qing Zhang Ya-jun Wang Xiao-wen Hong Ying Yang Nanjing University of Science and Technology Nanjing210094China Jiangsu Yongfeng Mechanics Co. LtdNanjing210094China

The failure mechanism of a cylindrical shell cut into fragments by circumferential detonation collision was experimentally and numerically investigated.A self-designed detonation wave regulator was used to control the detonation and cut the shell.It was found that the self-designed regulator controlled the fragment shape.The macrostructure and micro-characteristics of fragments revealed that shear fracture was a prior mechanism,the shell fractured not only at the position of detonation collision,but the crack also penetrated the shell at the first contact position of the Chapmen-Jouguet(C-J)wave.The effects of groove number and outer layer thickness on the fracture behavior were tested by simulations.When the thickness of the outer layer was 5e18 mm,it has little effect on fragmentation of the shell,and shells all fractured at similar positions.The increase of the groove number reduced the fracture possibility of the first contact position of the C-J wave.When the groove number reached 7 with a 10 mm outer layer(1/4 model),the fracture only occurred at the position of detonation collision and the fragment width rebounded.

关键词： Detonation wave Circumferential detonation collision Fracture mechanism Fragmentation control

Clinical outcome of treating intractable hematospermia using holmium laser incision through a ureteroscope

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Asian Journal of Andrology 2016年第1期18卷 140-142页

作者： Xiao-Jun Wu Heng Zhang Yong-Quan Wang Yi Zhi Ji Zheng Peng He wei-bing li Zhan-Song Zhou Institute of Urinary Surgery Southwest Hospital Third Military Medical University Chongqing 400038 China

Aconventional procedure for treating hematospermia is to insert a ureteroscope or seminal vesiculoscope into the prostatic utr/de through the urethra, and then dilate the ejaculatory duct opening using the scope or the catheter. However, the ejaculatory duct stenosis may occur after the simple ureteroscopy. We compared the outcomes of treating hematospermia using holmium laser incision through a ureteroscope and using simple ureteroscopy. Retrospective method was used to analyze 67 intractable hematospermia cases. Varying degrees of ejaculatory duct stenosis or obstruction were observed in all the patients. Postoperative follow-up was conducted for 6 months up to 3 years. Two patients who underwent the simple ureteroscopy experienced hematospermia recurrence in 6 and 8 months, respectively. No recurrence was found in all the patients who underwent the holmium laser incision. We have found that the holmium laser incision through a ureteroscope shows a better outcome than the simple ureteroscop~

关键词： TRANSURETHRAL SEMINAL VESICULOSCOPY EJACULATORY DUCT OBSTRUCTION DIAGNOSIS PERSISTENT ULTRASOUND EXPERIENCE

The near-infrared dye IR-61 restores erectile function in a streptozotocin-induced diabetes model via mitochondrial protection

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Asian Journal of Andrology 2021年第3期23卷 249-258页

作者： Xiao-Feng Yue Chong-Xing Shen Jian-Wu Wang lin-Yong Dai Qiang Fang Lei Long Yi Zhi Xue-Ru li Ya-wei Wang Gu-Fang Shen Zu-Juan liu Chun-Meng Shi wei-bing li Departm ent of Urology The Third Affiliated Hospital of Chongqing Medical University(Gener Hospital)Chongqing 401120China lnstitute of Rocket Force Medicine State Key Laboratory of TraumaBurns and Combined InjuryThird Military Medical UniversityChongqing 400038China Department of Ophthalmology The Third Affiliated Hospital of Chongqing M edical University(Gener Hospital)Chongqing 401120China

This study aimed to evaluate the therapeutic effect of IR-61,a novel mitochondrial heptamethine cyanine dye with antioxidant effects,on diabetes mellitus-induced erectile dysfunction(DMED).Eight-week-old male Sprague-Dawley rats were intraperitoneally injected with streptozotocin(STZ)to induce type 1 diabetes.Eight weeks after STZ injection,all rats were divided into three groups:the control group,DM group,and DM+IR-61 group.In the DM+IR-61 group,the rats were administered IR-61(1.6 mg kg-1)twice a week by intravenous injection.At week 13,erectile function was evaluated by determining the ratio of the maximal intracavernous pressure to mean arterial pressure,and the penises were then harvested for fluorescent imaging,transmission electron microscopy,histological examinations,and Western blot analysis.Whole-body imaging suggested that IR-61 was highly accumulated in the penis after intravenous injection.IR-61 treatment significantly improved the maximal ICP of diabetic rats.Additionally,IR-61 ameliorated diabetes-induced inflammation,apoptosis,and phenotypic transition of corpus cavernosum smooth muscle cells(CCSMCs)in penile tissue.IR-61 also attenuated mitochondrial damage,reduced reactive oxygen species production in the corpus cavernosum and upregulated sirtuinl(SIRT1),sirtuin3(SIRT3),nuclear factor(erythroid-derived 2)-like 2(Nrf2),and heme oxygenase expression in penile tissue.In conclusion,IR-61 represents a potential therapeutic option for DMED by protecting the mitochondria of CCSMCs,which may be mediated by activation of the SIRT1,SIRT3,and Nrf2 pathways.

关键词： corpus cavernosum smooth muscle cells diabetes erectile dysfunction IR-61 mitochondria

Spiral wave chimeras in populations of oscillators coupled to a slowly varying diffusive environment

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Frontiers of physics 2023年第1期18卷 71-83页

作者： Lei Yang Yuan He bing-wei li School of Physics Hangzhou Normal UniversityHangzhou 311121China

Chimera states are firstly discovered in nonlocally coupled oscillator systems.Such a nonlocal coupling arises typically as oscillators are coupled via an external environment whose characteristic time scaleτis so small(i.e.,τ→0)that it could be eliminated adiabatically.Nevertheless,whether the chimera states still exist in the opposite situation(i.e.,τ≫1)is unknown.Here,by coupling large populations of Stuart–Landau oscillators to a diffusive environment,we demonstrate that spiral wave chimeras do exist in this oscillator-environment coupling system even whenτis very large.Various transitions such as from spiral wave chimeras to spiral waves or unstable spiral wave chimeras as functions of the system parameters are explored.A physical picture for explaining the formation of spiral wave chimeras is also provided.The existence of spiral wave chimeras is further confirmed in ensembles of FitzHugh–Nagumo oscillators with the similar oscillator-environment coupling mechanism.Our results provide an affirmative answer to the observation of spiral wave chimeras in populations of oscillators mediated via a slowly changing environment and give important hints to generate chimera patterns in both laboratory and realistic chemical or biological systems.

关键词： spiral wave chimeras reaction-diffusion systems oscillator-environment coupling pattern formation