8 publications
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Published Subscription Review Article
Study on the Method of Constructing a System of Linear Equations for Calculating Aerodynamic DerivativesBy Nam Song Pak, Sol Song Pak, Won Hak Kim
Abstract: The aerodynamic derivatives can be calculated from the unsteady hydrodynamic forces experienced by the harmonic-oscillating vehicle. Until now, unsteady flow field analysis in aerodynamic derivative calculations has been applied mainly to thin bodies based on potential theory MSC. Nastran is a typical application based on potential theory MSC. Natran can calculate the aerodynamic derivatives of the vehicle relatively well in the subsonic region, but in the supersonic region, the fuselage …
Published in Journal of Experimental & Applied Mechanics · Vol. 16, Issue 3, 2025 · pp. 14–24 Read article →
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Published Subscription Original Research
A Method of Mesh Deformation for Flow Analysis Around Oscillating BodiesBy Phyong Guk Paek, Yun Hyok Kim, Sol Song Pak, Yong Chol Pak, Chong Il Hong
Abstract: In general, high-speed rotating machines are subjected to complex phenomena due to various reasons, such as increased noise and strong vibration due to dynamic unbalance, which affect the dynamic motion of rotating machines and are necessarily a problem to overcome. Therefore, it is necessary to have a mathematical model to simulate it, and a strong tool to solve the constructed model. Using fluid-structure coupling techniques, which are currently a powerful …
Published in Journal of Experimental & Applied Mechanics · Vol. 16, Issue 2, 2025 · pp. 35–42 Read article →
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Published Subscription Original Research
Study on the Rocking Phenomenon of Parachute RopeBy Tae Jin Pak, Sol Song Pak, Kwang Ho Kim, Kyong Jun Kim, Won Hak Kim
Abstract: With the constant development of computer technology and the development of numerical simulation techniques, the simulation of the dynamics of the parachute is becoming increasingly accurate. To eliminate the effects of large deformation of the grid in the conventional parachute simulation, we chose the parachute model using the smooth particle hydrodynamics method and performed a steady-state fluid-solid coupling numerical simulation, which is in good agreement with the calculated gas power …
Published in Trends in Mechanical Engineering & Technology · Vol. 15, Issue 2, 2025 · pp. 1–7 Read article →
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Published Subscription Review Article
Study on the Method of Prediction of Complete Inflation Time of ParachuteBy Wi Song Jon, Sol Song Pak, Won Hak Kim, Jong Dok Ri1, Jong Hwang
Abstract: In general, the parachute test is a long test period, expensive, and difficult to measure with accuracy, which makes it a very laborious and laborious task due to the strong nonlinearity of the fabric of the parachute. Therefore, attempts have been made to overcome this by using a parachute testbed or by simulation, but in our country, there is no numerical simulation of the parachute, and no research has been …
Published in Trends in Mechanical Engineering & Technology · Vol. 15, Issue 1, 2025 · pp. 25–31 Read article →
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Published Subscription Original Research
Effects of Bearing Design Parameter on Working Characteristics of Floating Ring BearingBy Son Gun Kwon, Chol Min Ri, Sol Song Pak
Abstract: The working stability of turbochargers supported by floating ring bearings depends on not only the structure of the rotors but also working characteristic of floating ring bearings. These working characteristics are related to working conditions and design parameters of floating ring bearings. The main goal of this research is to investigate the working characteristics of bearings by design parameters of floating ring bearings. In order to study the working characteristics …
Published in Journal of Experimental & Applied Mechanics · Vol. 15, Issue 3, 2024 · pp. 39–52 Read article →
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Published Subscription Review Article
Understanding Side-wind Dynamics and Deciphering Ringsail Parachute DriftBy Kum Gwon Choe, Yu Mi Sin, Sol Song Pak, Ji Yong Ri, Jong Gil Pak
Abstract: The geometric complication caused by the "rings" and "sails" used to make the parachutist's canopy provides a considerable computationally problem, which is the focus of this paper's fluid–structure interaction (FSI) modeling of ringsail parachutes. Based on the sustained space-time FSI (SSTFSI) method, we have developed an FSI simulation of ringsail jumping devices. The FSI Geometric Smoothing Technique and the Homogenized Modeling of Geometric Porosity represent a pair of the above …
Published in Journal of Experimental & Applied Mechanics · Vol. 15, Issue 1, 2024 · pp. 1–12 Read article →
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Published Subscription Review Article
Improving Parachute Efficiency: The Function of LS- Dyna in Fluid-structure Interaction SimulationBy Chang Kim, Kun Song Kim, Sol Song Pak, Kum Gwon Choe, Hyong Gyu Jon
Abstract: As an accompaniment to assessment of DGA Aeronautical Systems created a simulation and model-building capability to gain a better understanding of the parachute dynamic behavior and to maximize the parachute systems flight tests. This work reports on the latest developments in Arbitrary Lagrangian mathematical (ALE) methods for analyzing the properties of the quasi-steady state descent phases and canopy inflation. Thus far, none of the simulations of the endless mass type …
Published in Journal of Experimental & Applied Mechanics · Vol. 15, Issue 1, 2024 · pp. 44–56 Read article →
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Published Open access Original Research
Study on the Profile and Flow Field Variation of Parachute Coating by Seven-hole Probe MethodBy Kun Song Kim, Sun Ri, Sol Song Pak, Nam Song Pak, Kum Song Kim
Abstract: In general, the parachute test is a long test cycle, expensive, and difficult to measure with accuracy, which makes it a very laborious and time-consuming task. Therefore, attempts have been made to overcome this by using a parachute test stand or by simulation, but in our country, there is no numerical simulation of the parachute and there is no research on it. In this paper, the variation of the shape …
Published in Journal of Aerospace Engineering & Technology · Vol. 14, Issue 1, 2024 · pp. 26–37 Read article →