In order to study the effects of lateral flow on the underwater missile vertical launching process considering the hydrodynamic effect, a horizontal fluid dynamics model was developed. We offered the numerical computa...In order to study the effects of lateral flow on the underwater missile vertical launching process considering the hydrodynamic effect, a horizontal fluid dynamics model was developed. We offered the numerical computation method in this process by using the fluent of CFD ( Computational Fluid Dynamics)software. Based on the specific examples, we carried out the computation of the model's drag coefficient, lift coefficient and pitching moment with its launching process. The computation results agree with the results of the experiment and the error between them is less than 10%. It shows that this computation method is viable and can be used in the system design, and the analysis of missile motion and basic structure intensity.展开更多
The feasibility of providing the tank a limited anti helicopter ability with gun launched missile is studied. A type of simulation model of gun launched missile against attack helicopters is established. The simula...The feasibility of providing the tank a limited anti helicopter ability with gun launched missile is studied. A type of simulation model of gun launched missile against attack helicopters is established. The simulation and the parameter optimization of missile control system under various circumstances are done. The gun launched missile can directly hit the helicopters in the typical tracks, all the missdistances are less than 1?m and the maximum overload is less than available overload. Gun launched missile is a feasible choice for tanks against attack helicopters.展开更多
China’s HQ-2B is a point-de-fense missile system derived fromthe HQ-2.The article briefly intro-duced its main characteristics,com-ponents and the important improve-ments in the missile itself,the guid-ance system an...China’s HQ-2B is a point-de-fense missile system derived fromthe HQ-2.The article briefly intro-duced its main characteristics,com-ponents and the important improve-ments in the missile itself,the guid-ance system and the newly devel-oped launch facilities. GENERAL The HQ-2B surface-to-air missilesystem is an effective all-weatherand all-aspect point-defense weaponsystem which is the latest develop-展开更多
This paper describes China’s HQ 61 surface-to-air missile system, especially the main tactical and technical performances, missile aerodynamic configuration, propulsion system, warhead, guidance and electric system. ...This paper describes China’s HQ 61 surface-to-air missile system, especially the main tactical and technical performances, missile aerodynamic configuration, propulsion system, warhead, guidance and electric system. The paper also briefs the weapon’s launching facilities and operation process.展开更多
The gas and water flows during an underwater missile launch are numerically studied. For the gas flow, the explicit difference scheme of Non-oscillation and Non-free-parameter Dissipation (NND) is utilized to solve th...The gas and water flows during an underwater missile launch are numerically studied. For the gas flow, the explicit difference scheme of Non-oscillation and Non-free-parameter Dissipation (NND) is utilized to solve the Euler equations for compressible fluids in the body-fitted coordinates. For the water flow, the Hess-Smith method is employed to solve the Laplace equation for the velocity potential of irrotational water flows based on the potential theory and the boundary element method. The hybrid Eulerian-Lagrangian formulation for the free boundary conditions is used to compute the changes of the free surface of the exhausted gas bubble in time stepping. On the free surface of the exhausted gas bubble, the matched conditions of both the normal velocities and pressures are satisfied. From the numerical simulation, it is found that the exhausted gas bubble grows more rapidly in the axial direction than in the radial direction and the bubble will shrink at its "neck" finally. Numerical results of the movement of the shock wave and the distribution of the Mach number and the gas pressure within the bubble were presented, which reveals that at some time, the gas flow in the Laval nozzle is subsonic and the gas pressure in the nozzle is very high. Influences of various initial missile velocities and chamber total pressures and water depths on both the time interval when the gas flow in the nozzle is subsonic and the peak of the gas pressure at the nozzle end were discussed. It was suggested that a reasonable adjustment of the chamber total pressure can improve the performance of the engine during the underwater launch of missiles.展开更多
A new concept is presented for air-to-air missile which is dynamic attack zone after being launched in random wind field. This new concept can be used to obtain the 4-dimensional (4-D) information regarding the dyna...A new concept is presented for air-to-air missile which is dynamic attack zone after being launched in random wind field. This new concept can be used to obtain the 4-dimensional (4-D) information regarding the dynamic envelope of an air-to-air missile at any flight time airned at different flight targets considering influences of random wind, in the situation of flight fighters coop- crated with missiles fighting against each other. Based on an air-to-air missile model, some typical cases of dynamic attack zone after being launched in random wind field were numerically simulated. Compared with the simulation results of traditional dynamic envelope, the properties of dynamic attack zone after being launched are as follows. The 4-D dynamic attack zone after being launched is inside traditional maximum dynamic envelope, but its forane boundary is usually not inside traditional no-escape dynamic envelope; Traditional dynamic attack zone can just be reliably used at launch time, while dynamic envelope after being launched can be reliably and accurately used during any flight antagonism time. Traditional envelope is a special case of dynamic envelope after being launched when the dynamic envelope is calculated at the launch time: the dynamic envelope after being launched can be inflt, enced by the random wind field.展开更多
Numerical investigations on the launch process of a gun-launched missile from the muz- zle of a cannon to the free-flight stage have been performed in this paper. The dynamic overlapped grids approach are applied to d...Numerical investigations on the launch process of a gun-launched missile from the muz- zle of a cannon to the free-flight stage have been performed in this paper. The dynamic overlapped grids approach are applied to dealing with the problems of a moving gun-launched missile. The high-resolution upwind scheme (AUSMPW +) and the detailed reaction kinetics model are adopted to solve the chemical non-equilibrium Euler equations for dynamic grids. The development process and flow field structure of muzzle flows including a gun-launched missile are discussed in detail. This present numerical study confirms that complicated transient phenomena exist in the shortly launching stages when the gun-launched missile moves from the muzzle of a cannon to the free- flight stage. The propellant gas flows, the initial environmental ambient air flows and the moving missile mutually couple and interact. A complete structure of flow field is formed at the launching stages, including the blast wave, base shock, reflected shock, incident shock, shear layer, primary vortex ring and triple point.展开更多
文摘In order to study the effects of lateral flow on the underwater missile vertical launching process considering the hydrodynamic effect, a horizontal fluid dynamics model was developed. We offered the numerical computation method in this process by using the fluent of CFD ( Computational Fluid Dynamics)software. Based on the specific examples, we carried out the computation of the model's drag coefficient, lift coefficient and pitching moment with its launching process. The computation results agree with the results of the experiment and the error between them is less than 10%. It shows that this computation method is viable and can be used in the system design, and the analysis of missile motion and basic structure intensity.
文摘The feasibility of providing the tank a limited anti helicopter ability with gun launched missile is studied. A type of simulation model of gun launched missile against attack helicopters is established. The simulation and the parameter optimization of missile control system under various circumstances are done. The gun launched missile can directly hit the helicopters in the typical tracks, all the missdistances are less than 1?m and the maximum overload is less than available overload. Gun launched missile is a feasible choice for tanks against attack helicopters.
文摘China’s HQ-2B is a point-de-fense missile system derived fromthe HQ-2.The article briefly intro-duced its main characteristics,com-ponents and the important improve-ments in the missile itself,the guid-ance system and the newly devel-oped launch facilities. GENERAL The HQ-2B surface-to-air missilesystem is an effective all-weatherand all-aspect point-defense weaponsystem which is the latest develop-
文摘This paper describes China’s HQ 61 surface-to-air missile system, especially the main tactical and technical performances, missile aerodynamic configuration, propulsion system, warhead, guidance and electric system. The paper also briefs the weapon’s launching facilities and operation process.
文摘The gas and water flows during an underwater missile launch are numerically studied. For the gas flow, the explicit difference scheme of Non-oscillation and Non-free-parameter Dissipation (NND) is utilized to solve the Euler equations for compressible fluids in the body-fitted coordinates. For the water flow, the Hess-Smith method is employed to solve the Laplace equation for the velocity potential of irrotational water flows based on the potential theory and the boundary element method. The hybrid Eulerian-Lagrangian formulation for the free boundary conditions is used to compute the changes of the free surface of the exhausted gas bubble in time stepping. On the free surface of the exhausted gas bubble, the matched conditions of both the normal velocities and pressures are satisfied. From the numerical simulation, it is found that the exhausted gas bubble grows more rapidly in the axial direction than in the radial direction and the bubble will shrink at its "neck" finally. Numerical results of the movement of the shock wave and the distribution of the Mach number and the gas pressure within the bubble were presented, which reveals that at some time, the gas flow in the Laval nozzle is subsonic and the gas pressure in the nozzle is very high. Influences of various initial missile velocities and chamber total pressures and water depths on both the time interval when the gas flow in the nozzle is subsonic and the peak of the gas pressure at the nozzle end were discussed. It was suggested that a reasonable adjustment of the chamber total pressure can improve the performance of the engine during the underwater launch of missiles.
文摘A new concept is presented for air-to-air missile which is dynamic attack zone after being launched in random wind field. This new concept can be used to obtain the 4-dimensional (4-D) information regarding the dynamic envelope of an air-to-air missile at any flight time airned at different flight targets considering influences of random wind, in the situation of flight fighters coop- crated with missiles fighting against each other. Based on an air-to-air missile model, some typical cases of dynamic attack zone after being launched in random wind field were numerically simulated. Compared with the simulation results of traditional dynamic envelope, the properties of dynamic attack zone after being launched are as follows. The 4-D dynamic attack zone after being launched is inside traditional maximum dynamic envelope, but its forane boundary is usually not inside traditional no-escape dynamic envelope; Traditional dynamic attack zone can just be reliably used at launch time, while dynamic envelope after being launched can be reliably and accurately used during any flight antagonism time. Traditional envelope is a special case of dynamic envelope after being launched when the dynamic envelope is calculated at the launch time: the dynamic envelope after being launched can be inflt, enced by the random wind field.
基金financially supported by the National Natural Science Foundation of China (No. 11402119)the National Defence Pre-research Foundation of China (No. 404040302)
文摘Numerical investigations on the launch process of a gun-launched missile from the muz- zle of a cannon to the free-flight stage have been performed in this paper. The dynamic overlapped grids approach are applied to dealing with the problems of a moving gun-launched missile. The high-resolution upwind scheme (AUSMPW +) and the detailed reaction kinetics model are adopted to solve the chemical non-equilibrium Euler equations for dynamic grids. The development process and flow field structure of muzzle flows including a gun-launched missile are discussed in detail. This present numerical study confirms that complicated transient phenomena exist in the shortly launching stages when the gun-launched missile moves from the muzzle of a cannon to the free- flight stage. The propellant gas flows, the initial environmental ambient air flows and the moving missile mutually couple and interact. A complete structure of flow field is formed at the launching stages, including the blast wave, base shock, reflected shock, incident shock, shear layer, primary vortex ring and triple point.