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Development and evolution of internal ballistics

As early as 1793, J.-L. Lagrange, a French mechanic and mathematician, put forward the hypothesis that the air velocity in the bore was linearly distributed, that is, he began to study the basic theory. 1864, French scientist H. Rezal established the interior ballistic energy equation by applying the first law of thermodynamics; From 1868 to 1875, British physicist A. Noble and chemist F. Abel determined the state equation of gunpowder gas according to the test of closed bomb; At the end of 19, French scientist P. Vieille summarized the previous experience in studying the combustion of black powder, and put forward the hypothesis of geometric combustion law according to the parallel layer combustion phenomenon of smokeless powder, thus establishing the shape function expressing the gas generation law and the burning rate function determined by experimental methods. At this time, these theories can be applied to establish a mathematical model and give a trajectory solution representing the trajectory law. Therefore, the theory of internal ballistics based on geometric combustion law and Lagrange hypothesis is formed in theory and practice, that is, classical internal ballistics.

After the 1920s, with the development of gas dynamics and the need for weapons to develop in the direction of high muzzle velocity, the phenomenon of material flow in bore became the main object of basic theoretical research, and gradually formed a new academic field. Its basic content is to describe the interior ballistic process by applying the aerodynamic principle, establish the corresponding mathematical model, and get the ballistic solution of unsteady flow. The British physicist A.E.H Love and mathematician F.B. Pidak first put forward the analytical solution. They put forward the single-phase hypothesis of instantaneous combustion of gunpowder and established the simplest mathematical model. However, due to calculation difficulties, the research progress is slow. Until 1950s, with the development of computer, the model was constantly improved and played its due role. In 1970s, the gas-solid mixed phase model under the condition of layer-by-layer combustion of powder particles established by K.K. Guo and P.S. Goff appeared. Ballistic solution can basically reflect the distribution law of air velocity and pressure in the bore, which provides the necessary theoretical basis for studying the phenomenon of pressure wave in the bore, and makes the theory of ballistic aerodynamics in unsteady flow perfect and developed. 1979, Chinese scholars put forward the theory of internal ballistic potential balance, and applied this theory to study the actual combustion law of gunpowder in the bore, and established the corresponding ballistic solution, thus forming a new and relatively complete internal ballistic theory different from the geometric combustion law. However, when dealing with the airflow in the bore, we still follow the Lagrangian hypothesis of classical internal ballistics.

Because the interior ballistic process has the characteristics of high temperature, high pressure, high speed and instantaneous, its measurement technology has its own characteristics accordingly, and it has developed into a special experimental research field. The earliest ballistic measurement was in 1740. British mathematician and military engineer B. Robbins used ballistic pendulum method to measure the initial velocity of the projectile. In the 65438+60s, P. LeBron invented the falling timer, which greatly improved the accuracy of measuring the initial velocity. Nobel, a British physicist, invented the copper column pressure measurement method to measure the maximum bore pressure of artillery, and applied it to the pressure fluctuation of closed exploder by tuning fork time measurement method. What is the cross-examination of acyl stalks planted in U Jun Street? Drumming? Hey? Hey? What's the point? What's the matter with you? After 1930s, a new method for measuring gun pressure was developed. What's the problem? Are you loyal to me? What's the matter with you? In 1946, the first generation of electronic computers came out at Aberdeen Weapon proving ground, which promoted the study of complex theoretical problems and made the development of ballistics enter a new stage. Since 1950s, with the development of electronic technology and computing technology, instruments such as speed measuring and pressure measuring instruments with automatic data processing function, thermocouples for measuring the temperature distribution of the gun body, microwave and laser interferometers for measuring the time-varying velocity of the projectile in the bore, and high-speed cameras for measuring the movement posture and flow field changes of the projectile in the bore have been widely used. Comprehensive multi-parameter synchronous measurement technology has been widely developed in experimental methods, providing more and more comprehensive data.

In addition, the research on using liquid propellant as gun energy has also made progress, and its ignition, gas generation and pressure change laws are different from those using solid propellant energy. It has become a new research content of internal ballistics.