• 한국군사과학기술학회지
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• 제11권6호
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• pp.164-171
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• 2008

A modified generalized particle algorithm, MGPA, was suggested to improve the computational efficiency of standard SPH method in numerical analysis of high speed impact behavior. This method uses a numerical failure mechanism than material failure models to describe the target penetration. MGPA algorithm was more effective to describe the impact phenomena and new boundaries produced during the calculation process were well recognized and treated in the target penetration problem of a bullet. When bullet perforation problems were analyzed by this method, MGPA algorithm calculation gives the stable numerical solution and stress oscillation or particle penetration phenomena were not shown. The error range in ballistic velocity limit is less than $2{\sim}13%$ for various target thickness.

• 한국군사과학기술학회지
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• 제6권3호
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• pp.62-73
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• 2003

The characteristics of constitutive equations, for hydrocodes, were Investigated by the comparison between the smoothed particle hydrodynamcis simulation and the experiment of rod impact test which resulted in a deformation history of impacting front where high strain and high strain rate dominate. The constitutive equations used in the simulation Is J-C(Johnson-Cook) model, Z-A(Zerilli-Armstrong) model, and S-C-G(Steinberg-Cochran-Guinan) model. The modification of Z-A model, based on the increased effect of strain-rate hardening, showed better correlation with expriment.

• 한국정밀공학회지
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• 제21권1호
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• pp.189-196
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• 2004

A modified generalized particle algorithm, MGPA, was suggested to improve the calculation efficiency of standard SPH Method in numerical analysis of high speed impact behavior. MGPA had a new weight function to reduce computation time. The efficiency of this method was proven through calculation for the sample problems of one dimensional rod impact problem and two dimensional plate impact problem. The MGPA method reduced the calculation error and stress oscillation near the boundaries. The validity of this approach was shown by the comparison with ABAQUS results in two dimensional plate impact problem.

• 대한기계학회논문집A
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• 제27권10호
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• pp.1738-1747
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• 2003

Smoothed Particle Hydrodynamics (SPH), a pure Lagrangian numerical method, is applied to analysis of penetration phenomenon of bumper plate which is installed outside of spacecraft hull to protect the spacecraft against hypervelocity meteorite impact. Effects of SPH parameters, such as artificial viscosities, smoothing lengths, numbers of particles and time increments, are analysed by comparing the SPH simulation results with experimental ones with regard to subsequent formation of debris cloud. An optimum range of parameter values is determined by error analysis and various SPH numerical results are compared with experiments.