• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.2
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• pp.173-180
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• 2015

North Korea has developed ballistic missiles over the past 30 years. It is believed that they have a variety of ballistic missiles more than 1,000. Because these ballistic missiles threaten South Korea directly, accurate analysis of them is essential. Flight trajectories of the ballistic missiles are generally changed by means of adjusting payload weight, Isp, flight path angle, and cut-off time. The flight path angle is widely used to control the missile range. However it is difficult to predict the missile trajectory exactly in real operational environment because the missile could be launched according to its intention and purpose. This work analyzed the 1,000 km range MRBM's trajectory characteristics from adjusting flight path angle which is depressed as well as lofted method. The analysis of missile trajectory characteristics is based on the simulation of the missile trajectory model developed by KNDU research team.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.1
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• pp.79-85
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• 2008

Generally Solid Rocket Motor(SRM) has advantages like this - safety, simplicity and flexibility in design and manufacturing process. However, once propellant grain shape and nozzle throat area are determined, modification of thrust magnitude is nearly impossible. Recently, methods for controlling the thrust magnitude of SRM are vigorously developed. This paper predicts internal ballistic performance variation, especially thrust of SRM by means of Linear Approximation according as chamber pressure or nozzle throat area is changed. The results predicted by the proposed method are good agreement with the those of exclusive Ballistic Performance Prediction Program(SPP).

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.279-282
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• 2011

Projectile can be damaged during the storage and handling. Maximum range calculation of the ammunition was performed on the assumption that each projectiles have 1.5mm/3.3mm axisymetric dent on the surface. Drag coefficient for trajectory calculation was delivered from CFD using commercial software FLUENT. In the result of CFD, damaged projectiles those have 1.5mm/3.3mm axisymetric dent have similar drag coefficient compare with normal projectile in the region of subsonic. But, in supersonic region, drag coefficient was increased 3%, 9% each in average. In the result of trajectory calculation, Maximum rage was decreased 1%, 3% each.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.3
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• pp.251-258
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• 2009

At the stage conceptual design, combat vehicle is classified into three general categories of fire power, mobility and physical properties of system. The present research is restricted to fire power and its optimization. At the stage of conceptual designing of system, it is appropriate to consider major variables affecting fire power - including the weight of bullet, which exerts a direct influence on destroying effect, maximum range which takes long range firing in consideration. To estimate the maximum firing range, a simple interior ballistic and an exterior ballistic model were built by using the lumped parameter method, Le Duc method and point mass trajectory model. Design of experiment and regression analysis was used to derive simulations of fire power. Finally, response surface models were built and design variables were analyzed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.215-218
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• 2007

Internal Ballistic modeling and performance prediction for solid propellant micro thruster was performed with heat loss to the chamber wall as an important factor of miniaturization. Simple l-D end-burner type thruster and general HTPB-AP type composite propellant were selected for computation model. The results showed that the performance loss with the heat loss to the surroundings becomes larger as the surface-to-volume ratio is increased. In this case, the total impulse was reduced about 3% of the case in adiabatic condition.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.3
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• pp.56-61
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• 2014

Two erosive burning models were applied to compare analysis results of ballistic for the internal ballistics of solid rocket motors. By comparing motor tests with results of analysis, the variance of a grain shape was analyzed and coefficients of erosive burning were drawn. Results of comparison presents that the coefficient of erosive burning was proportional to the change of burning area, while inversely proportional to the change of cross area.

• Journal of the Korea Society for Simulation
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• v.20 no.2
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• pp.41-48
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• 2011

Naval Gun FCS(Fire Control System) is the most fundamental weapon system in Naval Combat System. Simulationbased verification of FCS is mandatory before sea trial since ballistic solution needs complicated process and uses almost all information produced by own ship sensors. The FCS simulation method is proposed for verification of naval gun FCS and applicable to the FCS design depending on combat system development phase based on available data in each design phase. Verified FCS through proposed simulation method is adapted in real naval combat system and the performance has been proven by sea trial.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.121-125
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• 2010

In this study, we have constructed this algorithm that theoretical method for prediction performance of the internal ballastic analysis. And we have confirmed reliability, compared the value calculated by realized program with the value computed by modeling program. A basic concept of algorithm expresses combustion phenomenon to move each factor(node) according to the time increment like as Finite element method. And we have confirmed this realized program has sufficient possibility to utilize in the internal ballastic analysis.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.1
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• pp.95-104
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• 2016

To make a firing table of artillery with trajectory simulation, a precise trajectory model which corresponds with real firing test is required. Recent 4-DOF modified point mass trajectory model is considered accurate as a theoretical model, but fitting coefficients are used in calculation to match with real firing test results. In this paper, modified point mass trajectory model is presented and method of setting ballistic coefficient is introduced by applying optimization algorithms. After comparing two different algorithms, Particle Swarm Optimization and Covariance Matrix Adaptation - Evolutionary Strategy, we found that using CMA-ES algorithm gives fine optimization result. This fitting coefficient setting method can be used to make trajectory simulation which is required for development of new projectiles in the future.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.3
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• pp.228-239
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• 2019

In order to design the conceptual configuration of the short-range ballistic missile, the authors have established an optimization problem considering various aspects such as volume, aerodynamics, propulsion, structure, stability, and flight trajectory. For this purpose, the existing missile cases were analyzed and the design conditions and performance indices were derived. The performance of the whole system was analyzed by integrating each subsystem's model. Through the design example, we analyzed the relationship between various design variables and final performances.