Yaoke Wen

• Doctor of Engineering
• Professor (Associate) at Nanjing University of Science and Technology

Ensuring military and police personnel protection is vital for urban security. However, the impact response mechanism of the UHMWPE laminate used in ballistic helmets and vests remains unclear, making it hard to effectively protect the head, chest, and abdomen. This study utilized 3D-DIC technology to analyze UHMWPE laminate’s response to 9 mm lead...

In order to investigate the coupled damage mechanism of blunt impact and penetration of projectiles after penetrating bulletproof plates against human body targets, experiments were conducted using 6.8mm caliber armor-piercing bullet against gelatin targets with protective coatings. A numerical analysis model of projectile penetration into gelatin...

In human vulnerability assessment, the wound characteristics are derived from a single soft media penetration experiment, and there is a lack of mathematical model or algorithm to accurately describe the bullet motion (consider bullet rolling) and temporary cavity variation during bullet penetration into different soft media. This paper derives a b...

Ballistic helmets are an important part of personal protective equipment in war and are specifically designed to protect a person's head. The future trend is to improve the protective performance of helmets through the use of lightweight coatings, and polyurea, as one of the hottest elastomeric polymer coating materials in recent years, has excelle...

To evaluate the possibility of judging the degree of bone healing by wall thickness analysis provide reference for quantitative analysis of bone healing. Patients with lower limb fracture from April 2014 to October 2019 were recruited and divided into bone healing (group A), poor bone healing (group B), and nonunion (group C). Models were built in...

Ballistic gelatin, soap, and clay are three human simulated target materials commonly used in the field of wound ballistics research. Currently, there are more studies on ballistic gelatin’s mechanical properties, but rarely on clay and soap. In this paper, the mechanical properties of clay and soap materials were tested by using universal material...

To study the behind armor blunt trauma (BABT), a finite element model of a 5.8 mm rifle bullet penetrating the SiC/UHMWPE armor covered human torso was established. The human torso model comprises internal organs (heart, lung, liver, and stomach), skeleton (sternum, ribs, and spine), and muscle. It is assumed that the skeleton and muscle is linear...

Background: There are no recognized quantitative diagnostic criteria, which is one of the difficulties faced in trauma orthopedics. The purpose of this study is to quantitatively evaluate the degree of bone healing after internal fracture fixation with the individualized differential ratio method. Methods: Patients with a lower limb fracture treate...

Ultrahigh molecular weight polyethylene (UHMWPE) fiber orthogonally laid laminate is widely used in ballistic protection due to its excellent properties. Research on its response under bullet impact is meaningful for understanding the antiballistic mechanism and designing personal protection. In this article, three‐dimensional digital image correla...

Temporary cavity, one physical phenomenon in BABT reflects the dynamic response of biological tissues and is used to evaluate the trauma. To clarify the characteristics of cavity evolution during 9 mm Luger penetration, we obtain the deformation profiles by using an experimental method with a high-speed camera and thereby visualize the cavity forma...

Purpose: In wound ballistics, skin has obvious blocking effect in the biological target penetration of projectiles. An analytical description of skin mechanical properties under compression can set the basis for the numerical simulation and the evaluation of blocking effect. Methods: In this study, an improved three-parameter solid visco-elastic...

A modified split Hopkinson tension bar (SHTB) apparatus was used to investigate the dynamic tensile mechanical response of porcine muscles. A hollow aluminum alloy transmission bar and a semiconductor strain gauge were used to enhance the weak signal from porcine muscles. A ring-shaped copper pulse shaper was used to achieve stress equilibrium and...

Body armor that defeats the threat can still cause severe trauma by striking the thorax with its back face deformation (BFD). In this study, the 3D digital image correlation (DIC) technology was adopted to capture the dynamic BFD of a ceramic/UHMWPE body armor impact by a rifle bullet. The shape and size of the BFD time histories, deformation veloc...

Ultra-high-molecular-weight polyethylene (UHMWPE) fiber laminate is currently widely used in ballistic protection for its exceptional physical and mechanical properties. However, the dynamic compressive mechanism of UHMWPE laminate remains poorly understood. Therefore, the stress–strain relationship, the influence of different thickness, area, and...

Back-spalling of ceramic plates subjected to an impact is often observed phenomena, and a better understanding of back-spalling is critical for the design of protection systems. Numerical modeling is an effective means for modeling of structural failure caused by impacts. Among many numerical methods, Smoothed particle hydrodynamics (SPH) has advan...

Objective To study the mechanical properties of ballistic gelatin and establish a dynamic constitutive model by a numerical method to lay the foundation for the related research on wound ballistics. Methods First, 20% ballistic gelatin samples at 10°C were prepared, and then, the quasi static and dynamic compressive mechanical properties of the bal...

Introduction Penetrating wounds from explosively propelled fragments and bullets are the most common causes of combat injury. There is a requirement to assess the potential effectiveness of bullets penetrating human tissues in order to optimise preventive measures and wound trauma management. Methods An advanced voxel model based on the Chinese Vi...

In order to understand the formation and development law of the cavity with the small caliber rifle bullet penetrating the gelatin, an experiment was carried out, taking 4℃/10% concentration ratio, size of 300 mm×300 mm×300 mm gelatin as target, and the high speed photography for measurement. Three 5.56 mm SS109 bullet's high speed photography and...

In order to reveal the injury mechanism to human body from a pistol cartridge, the characteristics of pressure wave and the temporary cavity in the process of pistol cartridge penetrating gelatin were studied by a pressure and high-speed photography comprehensive testing system. In this study, 4℃, 10% concentration ratio, size of 350 mm×250 mm×175...

In the last few decades, various researches focus on the transient pressure in the behind armor blunt trauma. This paper presented a investigation on the transient pressure in the ballistic gelatin behind a soft body armor subjected to the impacting from three ammunitions. Experimental results show that three peaks appear on the pressure-time curve...

An accurate description of the motion of bullets in ballistic gelatin penetration can only be given if a corresponding mathematical model is derived. In this paper, change of the effective wetted area of the bullet is studied well with the increase of angle of yaw in the penetration process. By introducing an area detached ratio and the influence o...

We study the transient indirect effect of a rifle bullet on bone in the gelatin-bone composite target experimentally and computationally. The process of a 56 type 7.62-mm rifle bullet penetrating the composite target has been simulated using numerical method. The experiment provided the criteria for verifying the correctness of the numerical model....

The impact response of body armor composed of a ceramic plate with an ultrahigh molecular weight polyethylene (UHMWPE) fiber-reinforced composite and layers of UHMWPE fibers shielding a block of ballistic gelatin has been experimentally and numerically analyzed. It is a surrogate model for studying injuries to human torso caused by a bullet strikin...

In order to numerically simulate the terminal effect of bullet and fragment, the research status of ballistic gelatin physical properties is summarized firstly. The features of rate-dependent hyperelastic model and elastic-plastic hydrodynamic model are studied, respectively. The coefficients of equation of state of ballistic gelatin are concluded...

We experimentally and numerically analyze the impact response of ballistic gelatin behind armor comprised of a ceramic plate facing the incoming projectile with a fiber-reinforced composite backing. It is a surrogate model for studying injuries to human torso wearing body protection armor. Experiments were conducted to study the impact performance...

A series of ballistic tests were performed to investigate the bulletproof performance of UHMWPE composites. The temporal evolution of the UHMWPE composite plate back-face bulge height and diameter were captured by high-speed photography. The experiments show the composite plate were perforated when the impact velocity greater than 880m/s. The maxim...

Ultra-high molecular weight polyethylene (UHMWPE) fiber reinforced plastic (UFRP) is an integral part of hard body armor. The intensive study on the material characterization of UFRP can help to understanding the bulletproof mechanism and behind-armor blunt trauma (BABT) well, and thus improve the performance of body armor. The research presented i...

The dynamic process of bullet-gelatin interaction was studied using an FEA method. The numerical modelling was set up, and the numerical results are in good agreement with the experimental results. The penetration resistance and stress distribution of bullet in gelatin and the effect of angle of attack on gelatin damage were analyzed. The results s...

To study the steel sphere penetrating into ballistic gelatin at high velocity, experiments were carried out. Based on observation and analysis of experimental phenomenon and results, some criteria were proposed to verify the rationality of numerical model, feasibility and accuracy of the numerical methods. Three different formulation approaches, i....