Projectile

About: Projectile is a research topic. Over the lifetime, 13047 publications have been published within this topic receiving 115563 citations.

Dynamic Response of Cantilevered Rail Guns Attributed to Projectile/Gun Interaction—Theory

Abstract: An analytic approach is proposed to investigate the dynamic behavior of laboratory rail guns resulting from launching a projectile. The rail gun is modeled as a beam of finite length sitting on an elastic foundation with cantilevered support at the breech end of rails. The structural response of the rail is governed by a transient fourth-order differential equation with an extra term of elastic support (containment and insulator) subjected to a transient forcing function (a moving magnetic pressure). The complete solution of the governing equation is derived and illustrated in details. The displacement solution can be further derived to obtain strain and stress profile as well as dynamic response of the rail gun. This paper mainly reports the theoretic solution which provides a step forward to predict the dynamic behavior of rail guns

Ignition of Stagnation Point Flow by a Hot Body

Abstract: The ignition of a cold combustible mixture has been investigated at the forward stagnation region of a hot projectile. The occurrence of temperature maxima at the surface of the projectile acts as the ignition criterion. For quasi-stationary analysis, the characteristic (unknown) parameter of the problem is the surface (or ignition) temperature. The steady boundary layer equations describing the reacting flow have been solved numerically and the ignition temperatures for propane-air mixture are calculated for different values of the various non-dimensional physical parameters.

Numerical simulation of hypervelocity impacts of a projectile on laminated composite plate targets by means of improved SPH method

Abstract: This paper is concerned with the numerical simulation of hypervelocity impacts (HVIs) of a projectile on laminated composite plate targets. When the numerical simulation of HVIs is performed by means of a conventional smoothed particle hydrodynamics (SPH) method, loss of interactions among particles causes numerical fractures. To prevent the numerical fractures, the improved SPH method with new particle generation and particle merger techniques is used. For the laminated composite plate targets of weak delamination strength, a numerical laminated plate model for the SPH method is proposed to realize the discontinuity of stresses between neighboring layers of the laminated composite plate targets. The numerical simulation was carried out for an aluminum projectile striking to laminated graphite/epoxy (Gr/Ep) composite plate targets with several different layup configurations. Through the numerical simulation, the HVI responses of the projectile on the laminated composite plate targets are discussed.

Dynamic plasma screening effects on semiclassical inelastic electron–ion collisions in dense plasmas

Abstract: In dense plasmas, dynamic plasma screening effects are investigated on 1s→2p dipole transition probabilities for electron-impact excitation of hydrogenic ions. The electron–ion interaction potential is considered by introduction of the plasma dielectric function. A semiclassical straight-line trajectory method is applied to the path of the projectile electron in order to visualize the semiclassical transition probability as a function of the impact parameter, projectile energy, and plasma parameters. The transition probability including the dynamic plasma screening effect is always greater than that including the static plasma screening effect. When the projectile velocity is smaller than the electron thermal velocity, the dynamic polarization screening effect becomes the static plasma screening effect. When the projectile velocity is greater than the electron thermal velocity, then the interaction potential is almost unshielded. The difference between the dynamic and static plasma screening effects is mo...