• Proceedings of the KSME Conference
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• 2002.08a
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• pp.87-90
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• 2002

Computational study has been undertaken to investigate the aerodynamic influence of side jet on a supersonic missile and to find a similarity condition between the flight condition and the wind tunnel testing. Tasks were performed to validate the existing Raytheon test body with side jet, to simulate the flow inside the supersonic wind tunnel, and to compare the flow fields between the missile in free flight and that in the wind tunnel. Then sub-scale model of body-tail configuration was analyzed to estimate the influence of the side jet on the missile components. It Is found that the influence of side Jet is not as significant on the tail region as on the body surface and a simple algebraic formula for aerodynamic coefficients accounting for the side jet as a point force may be cautiously utilized in setting up control logic.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.2
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• pp.185-194
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• 2016

It is essential for generating the synthetic image to test and evaluate a guided missile system in the hardware-in-the-loop simulation. In order to make the evaluation results to be more reliable, the extent of fidelity and rendering performance of the synthetic image cannot be left ignored. There are numerous challenges to simulate the LWIR sensor signature of sea surface depending on the incident angle, especially in the maritime environment. In this paper, we investigate the key factors in determining the apparent temperature of sea surface and propose the approximate formula consisting of optical characteristics of sea surface and sky radiance. We find that the greater the incident angle increases, the larger the reflectivity of sea surface, and the greater the water vapor concentration in atmosphere increases, the larger the amount of sky radiance. On the basis of this information, we generate the virtual maritime environment in LWIR region using the SE-WORKBENCH, physically based rendering software. The margin of error is under seven percentage points.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.4
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• pp.5-14
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• 2006

The correct and opportune decision of reengaging the intercepted target is required in order to enhance the engagement performance of the surface to air missile systems that has the ability to defense or attack against various targets at the same time. The engagement efficiency and success of these systems will be largely enhanced by assigning quickly its system resources to the intercepted target and minimizing the waste of system resources for the target which is not able to attack any more. The kill-assessment algorithm has to be able to evaluate automatically whether various targets intercepted by missiles are killed or not on the basis of the reasonable confidence level. The definition of kill assessment is discussed and the kill assessment algorithm is designed reliably by using Kalman filter and a probability theory. Finally its performance is evaluated and analyzed by the Monte Carlo simulation.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1822-1825
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• 2003

A practical range estimator based on the robust Kalman filter is proposed to solve the range estimation problem for surface to air missile(SAM) homing guidance. Apart from the previous works based on the extended Kalman filter(EKF) with bearing only measurement, the proposed scheme makes use of line-of-sight(LOS) rate to ensure the fast convergency at long-range. In this reason, the robust Kalman filter is considered to deal with LOS rate measurement error. The recursive linear structure of proposed filter is easy to implement and make it possible to reduce computational burdens. Moreover, it shows good estimation performance without specific guidance law such as oscillation proportional navigation guidance(OPNG).

• Strategy21
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• s.41
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• pp.52-84
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• 2017

After finishing Cold War, the U.S. Navy's ability to Sea control has been gradually eroded last 15-20 years. The global security environment demands that the surface Navy rededicate itself to sea control, as a new group of potential adversaries is working to deny U.S. navy command of the sea. China has been increasing their sea denial capability, such as extended anti-surface cruise missile and anti-surface ballistic missile. To cope with this situation, the U.S. Naval Surface Forces Command has announced Surface Forces Strategy: Return to Sea Control. It is a new operating and organizing concept for the U.S. surface fleet called 'distributed lethality'. Under distributed lethality, offensive weapons such as new ASCMs are to be distributed more widely across all types of Navy surface ships, and new operational concept for Navy surface fleet's capability for attacking enemy ships and make it less possible for an enemy to cripple the U.S. fleet by concentrating its attack on a few very high-value Navy surface ships. By increasing the lethality of the surface ships and distributing them across wide areas, the Navy forces potential adversaries to not only consider the threat from our carrier-based aircraft and submarines, but they now consider the threat form all of those surface ships. This idea of using the distributed lethality template to generate surface action groups and adaptive force package and to start thinking about to increase the lethal efficacy of these ships. The U.S. Navy believes distributed lethality increases the Navy's sea control capability and expands U.S. conventional deterrence. Funding new weapons and renovated operating concept to field a more lethal and distributed force will enable us to establish sea control, even in contested area. The U.S. Navy's Surface Forces Strategy provides some useful implications for The ROK Navy. First the ROK Navy need to reconsider sea control mission. securing sea control and exploiting sea control are in a close connection. However, recently the ROK Navy only focuses on exploiting sea control, for instance land attack mission. the ROK Navy is required to reinvigorate sea control mission, such as anti-surface warfare and anti-air warfare. Second, the ROK Navy must seek the way to improve its warfighting capability. It can be achieved by developing high-edge weapons and designing renewed operating concept and embraced new weapon's extended capabilities.

• 한국전산유체공학회:학술대회논문집
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• 2002.05a
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• pp.41-46
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• 2002

Computational study has been undertaken to investigate the aerodynamic influence of side jet on a supersonic missile and to find a similarity condition between the flight condition and the wind tunnel testing. Tasks were peformed to validate the existing Raytheon test body with side jet, to simulate the flow inside the supersonic wind tunnel, and to compare the flow fields between the missile in free flight and that in the wind tunnel. Then sub-scale model of body-tail configuration was analyzed to estimate the influence of the side jet on the missile components. It is found that the influence of side jet is not as significant on the tail region as on the body surface and a simple algebraic formula for aerodynamic coefficients accounting for the side jet as a point force may be cautiously utilized in setting up control logic.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.4
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• pp.43-56
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• 2009

In korean peninsular, aircraft defense with SAM (Surface-to-Air Missile) is very important because of short range of combat space in depth. Effective and successful defense operation largely depends on two factors, SAM's location and the number of SAM for each target based on missile's availability in each SAM's location. However, most previous papers have handled only the former. In this paper, we developed Set covering model which can handle both factors simultaneously and Multi-heuristic algorithm for solving allocation problem of the batteries and missile assignment problem in each battery. Genetic algorithm is used to decide optimal location of the batteries. To determine the number of SAM, a heuristic algorithm is applied for solving missile assignment problem. If the proposed model is applied to allocation of SAM, it will improve the effectiveness of air defense operations.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.3
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• pp.272-281
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• 2009

In this paper, three-dimensional optimal evasive maneuver patterns for air-to-surface attack missiles against proportionally navigated anti-air defense missiles were investigated. An interception error of the defense missile is produced by an evasive maneuver of the attack missile. It is assumed that the defense missiles are continuously launched during the flight of attack missile. The performance index to be minimized is then defined as the negative square integral of the interception errors. The direct parameter optimization technique based on SQP and a co-evolution method based on the augmented Lagrangian formulation are adopted to get the attack missile's optimal evasive maneuver patterns. The overall shape of the resultant optimal evasive maneuver is represented as a deformed barrel-roll.

• Journal of Aerospace System Engineering
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• v.15 no.6
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• pp.10-18
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• 2021

A flame deflector prevents a launch system from thermal damage by deflecting the exhaust flame of the launch vehicle. During the deflection of the flame, the flame deflector is subjected to a high-temperature and high-pressure flow, which results in thermal ablation damage at the surface. Predicting this ablation damage is an essential requirement to ensure a reliable design. This paper introduces a numerical method for predicting the ablation damage phenomena based on a one-way fluid-structure interaction (FSI) analysis. In the proposed procedure, the temperature and convective heat transfer coefficient of the exhaust flame are calculated using a fluid dynamics analysis, and then the ablation is calculated using a finite element analysis (FEA) based on the user-subroutine UMESHMOTION and Arbitrary Lagrangian-Eulerian (ALE) adaptive mesh technique in ABAQUS. The result of such an analysis was verified by comparison to the ablation test result for a flame deflector.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.1
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• pp.148-157
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• 2017

Miniature guided-bullet is an advanced military technology of developing guided missile which is designed to hit a target precisely while having easily carriable miniature size. A key issue of developing such system involves size reduction of the original guided missile system, and this in turn arouses stiffness issue regarding small and thin sized control surface. In this study, procedures on how to calculate the critical flutter speed of special type of control surface with the change of its dimension or material property is arranged. During this procedure, design parameters related to critical flutter speed are abridged to help preliminary design of similar structure even faster than time-consuming, and cumbersome computer analysis.