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The main challenge in preparing body armor is achieving a high protection level by using lightweight materials with minimum cost.

In this study, a three-hybrid multilayered armor system is prepared for protection against a ballistic impact wave. These armor systems consist of glass or ceramic tile as a front layer followed by three intermediate layers made of woven fiber reinforced polymer composites and a back layer made of either aluminum or polypropylene.

All armor systems were successful in impeding the projectile from perforating, that is materials selection played an important role in stopping the ballistic impact wave. Almost an identical ballistic behavior was recorded between the experimental and numerical simulation by using ANSYS AUTODYN which means that the simulation could be used in advance to reduce the time required for practical experiments and the cost of using materials in experimental tests will be lessened. The effect of projectile geometry also had been studied, and it showed a noticeable role in changing ballistic behavior.

The originality of this research is in using carbon and glass fiber which are woven together in addition to adding polypropylene layers in armor preparation.

The purpose of this paper is to study the operation performance of the high-speed ramjet kinetic energy projectile using solid fuel ramjet as power plant that is a new short-range and small caliber projectile.

The numerical investigation on combustion characteristic of polyethylene in high-speed ramjet kinetic energy projectile is carried out in this paper. The flow characteristics’ differences are analyzed when ramjet works or do not work, and both the combustion characteristics and propulsive performance are analyzed when ramjet works.

The results show that with the increase of the abscissa x, the flame front is close to solid fuel surface at first and then keeps away from solid fuel surface. With the increase of the abscissa x, the temperature of solid fuel surface and regression rate of solid fuel continues to increase before re-attachment point and then decreases, which a maximum locate at the re-attachment point. Both the average temperature and the regression rate on the surface of the solid fuel tend to rise as the increase of inflow Mach number. As the inflow of Mach number increases, the mass flow rate of gaseous fuel increases.

The research results can provide useful database for the subsequent research on high-speed ramjet kinetic energy projectile.

This paper studies the operation characteristics of the ramjet projectile, especially the effect of the change of the flight velocity on the performance of high-speed ramjet projectile.

The ability of light‐weight all fiber‐reinforced polymer‐matrix composite armor and hybrid composite‐based armor hard‐faced with ceramic tiles to withstand the impact of a non‐Armor‐ Piercing (non‐AP) and AP projectiles is investigated using a transient non‐linear dynamics computational analysis. The results obtained confirm experimental findings that the all‐composite armor, while being able to successfully defeat non‐AP threats, provides very little protection against AP projectiles. In the case of the hybrid armor, it is found that, at a fixed overall areal density of the armor, there is an optimal ratio of the ceramic‐to‐composite areal densities which is associated with a maximum ballistic armor performance against AP threats. The results obtained are rationalized using an analysis based on the shock/blast wave reflection and transmission behavior at the hard‐face/air, hard‐face/backing and backing/air interfaces, projectiles’ wear and erosion and the intrinsic properties of the constituent materials of the armor and the projectiles.

Traditionally, an armor-grade composite is based on a two-dimensional (2D) architecture of its fiber reinforcements. However, various experimental investigations have shown that armor-grade composites based on 2D-reinforcement architectures tend to display inferior through-the-thickness mechanical properties, compromising their ballistic performance. To overcome this problem, armor-grade composites based on three-dimensional (3D) fiber-reinforcement architectures have recently been investigated experimentally. The paper aims to discuss these issues.

In the present work, continuum-level material models are derived, parameterized and validated for armor-grade composite materials, having four (two 2D and two 3D) prototypical reinforcement architectures based on oriented ultra-high molecular-weight polyethylene fibers. To properly and accurately account for the effect of the reinforcement architecture, the appropriate unit cells (within which the constituent materials and their morphologies are represented explicitly) are constructed and subjected to a series of virtual mechanical tests (VMTs). The results obtained are used within a post-processing analysis to derive and parameterize the corresponding homogenized-material models. One of these models (specifically, the one for 0°/90° cross-collimated fiber architecture) was directly validated by comparing its predictions with the experimental counterparts. The other models are validated by examining their physical soundness and details of their predictions. Lastly, the models are integrated as user-material subroutines, and linked with a commercial finite-element package, in order to carry out a transient non-linear dynamics analysis of ballistic transverse impact of armor-grade composite-material panels with different reinforcement architectures.

The results obtained clearly revealed the role the reinforcement architecture plays in the overall ballistic limit of the armor panel, as well as in its structural and damage/failure response.

To the authors’ knowledge, the present work is the first reported attempt to assess, computationally, the utility and effectiveness of 3D fiber-reinforcement architectures for ballistic-impact applications.

The purpose of this paper is to investigate the ballistic impact response of square clamped fiber-metal laminates and monolithic plates consisting of different metal alloys using the ANSYS LS-DYNA explicit nonlinear analysis software. The panels are subjected to central normal high velocity ballistic impact by a cylindrical projectile.

Using validated finite element models, the influence of the constituent metal alloy on the ballistic resistance of the fiber-metal laminates and the monolithic plates is studied. Six steel alloys are examined, namely, 304 stainless steel, 1010, 1080, 4340, A36 steel and DP 590 dual phase steel. A comparison with the response of GLAss REinforced plates is also implemented.

It is found that the ballistic limits of the panels can be substantially affected by the constituent alloy. The stainless steel based panels offer the highest ballistic resistance followed by the A36 steel based panels which in turn have higher ballistic resistance than the 2024-T3 aluminum based panels. The A36 steel based panels have higher ballistic limit than the 1010 steel based panels which in turn have higher ballistic limit than the 1080 steel based panels. The behavior of characteristic impact variables such as the impact load, the absorbed impact energy and the projectile’s displacement during the ballistic impact phenomenon is analyzed.

The ballistic resistance of the aforementioned steel fiber-metal laminates has not been studied previously. This study contributes to the scientific knowledge concerning the impact response of steel-based fiber-metal laminates and to the construction of impact resistant structures.

The purpose of this study is to design and develop new spiral head projectiles undergoing ballistics impact.

The introduction of the rifled barrel in firearms made projectile spin during its flight path. The central translational velocity (impact velocity) is one parameter to defeat/penetrate the target in the penetration process. Another important parameter considered to be the shape of the projectile. Many types of projectile shapes have been designed to defeat the target. In the recent years, ogival nose shape is one of the well-known projectile shapes in use abundantly. The present research is made to design the nose shape so as to use the spin during the penetration of target effectively. In this study, a new spiral head projectile shape is proposed and designed, which uses the rotation of projectile (spin) for penetrating the Al7075-T6 target. When the ogive and new spiral head projectile is impacted on Al 7075-T6 target of 12.5 mm, 18 mm thicknesses at ordnance velocities, the residual velocity is evaluated numerically using ANSYS/Explicit Dynamics at normal impact condition. Two projectile materials, steel 4340 and tungsten alloy, are used as projectile materials. Along with the translational velocity, rotation velocities (spin rate) 13,000, 26,000 and 52,000 rad/s also provided to projectile. The residual velocities verses spin rate are plotted for different spiral angle projectiles for impact velocities 1,000–1,500 m/s, at normal impact conditions on the Al 7075-T6 target. Compared with the ogive nose projectile, the proposed new spiral head projectile made of tungsten alloy is significantly effective.

Spiral head projectile having tungsten alloy material gives encouraging results at 12.5 mm target thickness. The new spiral head projectile is damaged partially. At 18 mm target thickness impact conditions, it is observed that the projectile head is completely damaged. The effectiveness of spiral head projectile on a target plate thickness of 18 mm is considered to study the impact condition.

All the above results need to be experimentally verified. However, the basic numerical model used in the present study, i.e. the basic ogive nose numerical model with only translational energy, is well validated with penetration theory available in literatures.

The designed new spiral head projectile is only effective with tungsten alloy material within considered design parameters. For steel 4340 material, the spiral head projectile is less effective than the ogive nose projectile. In tungsten alloy projectiles, by observing all considered spiral angles, 30-degree spiral angle projectile gives the best performance at most of the considered impact velocity conditions.

The proposed research outputs are original, innovative and, have lot of importance in defence applications particularly in arms and ammunitions.

The purpose of this paper is to model a nacre-like composite material, consisting of tablets and polyurea tablet/tablet interfaces, B₄C. This composite material is being considered in the construction of the so-called backing-plate, a layer within a multi-functional/multi-layer armor system.

Considering the basic functions of the backing-plate (i.e. to provide structural support for the ceramic-strike-face and to stop a high-velocity projectile and the accompanying fragments) in such an armor system, the composite-material architecture is optimized with respect to simultaneously achieving high flexural stiffness and high ballistic-penetration resistance. Flexural stiffness and penetration resistance, for a given architecture of the nacre-like composite material, are assessed using a series of transient non-linear dynamics finite-element analyses. The suitability of the optimized composite material for use in backing-plate applications is then evaluated by comparing its performance against that of the rolled homogeneous armor (RHA), a common choice for the backing-plate material.

The results obtained established: a trade-off between the requirements for a high flexural stiffness and a high ballistic-penetration resistance in the nacre-like composite material; and overall superiority of the subject composite material over the RHA when used in the construction of the backing-plate within multi-functional/multi-layer armor systems.

This study extends the authors previous research on nacre-mimetic armor to optimize the architecture of the armor with respect to its flexural stiffness and ballistic-penetration resistance, so that these properties could be increased over the levels attained in the current choice (RHA) for the backing layer of multi-functional/multi-layer armor.

An aerothermodynamic design code for axisymmetric projectiles has been developed using a viscous‐inviscid interaction scheme. Separate solution procedures for the inviscid and the viscous (boundary layer) fluid dynamic equations are coupled by an iterative solution procedure. Non‐equilibrium, equilibrium and perfect gas boundary layer equations are included. The non‐equilibrium gas boundary layer equations assume a binary mixture (two species; atoms and molecules) of chemically reacting perfect gases. Conservation equations for each species include finite reaction rates applicable to high temperature air. The equilibrium gas boundary layer equations assume infinite rate reactions, while the perfect gas equations assume no chemical reactions. Projectile near‐wall and surface flow profiles (velocity, pressure, density, temperature and heat transfer) representing converged solutions to both the inviscid and viscous equations can be obtained in less than two minutes on minicomputers. A technique for computing local reverse flow regions is included. Computations for yawed projectiles are accomplished using a coordinate system transformation technique that is valid for small angle‐of‐attack. Computed surface pressure, heat transfer rates and aerodynamic forces and moments for 1.25 &le Mach No. &le 10.5 are compared to wind tunnel and free flight measurements on flat plate, blunt‐cone, and projectile geometries such as a cone‐cylinder‐flare.

The author developed a theory of optimal trajectories for air vehicles with variable wing area and conventional wings. He applied a new theory of singular optimal solutions and obtained the optimal flight in many cases. At first glance, the results may seem strange however, this is correct and this paper will show how this new theory may be used. The main idea of the research is in using the vehicle's kinetic energy for increasing the range of missiles and projectiles. The author shows that the range of a ballistic warhead can be increased 3‐4 times if an optimal wing is added to the ballistic warhead, especially a wing with variable area. If increased range is not needed, the warhead mass can be increased. The range of big gun shells can also be increased 3‐9 times. The range of aircraft may be improved 3‐15 percent and more. The results can be used for the design of aircraft, missiles, flying bombs and shells of big guns.

The author's aim is to offer a revolutionary method – the non‐rocket transfer of energy and thrust into Space with distances of millions of kilometers.

The author develops the theory and makes the computations.

The method is more efficient than transmission of energy by high‐frequency waves.

The method may be used for space launch and for acceleration of spaceships and probes to very high speeds, up to relativistic speed by current technology.

The research presented contains prospective projects which illustrate the possibilities of the suggested method.