• Journal of the Society of Naval Architects of Korea
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• v.39 no.1
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• pp.73-81
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• 2002

This study is performed to evaluate and design the vibration characteristics of the onboard machinery with resilient mountings. To reduce the vibration revel of onboard machinery with resilient mountings, it is important to evaluate and, if necessary modify vibration characteristics of the resilient mountings. In this study we have developed a program to calculate natural frequencies of the machinery with resilient mountings, forced vibration levels due to internal excitation force of the machinery itself and external excitation forces of the main engine and the propeller, and the force and motion transmissibility of the resilient mountings. The developed program can be also applied to optimal design of the resilient mountings for obtaining a target natural frequency and for achieving a minimum forced vibration level at the center of gravity of the machinery.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.3
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• pp.275-281
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• 2015

Mounts for shipboard equipment in naval ships play an important role for vibration and shock suppression. New large-capacity resilient mounts, SDR-D30 and SDR-D45, have been developed. This paper involves performance tests for the mount which have maximum load of 30 kN and 45 kN, respectively. The performance tests have been carried out for several mounts based on military standards, such as MIL-M-19863D(SH), MIL-M-21693C(SH), MIL-M-17508F(SH), and MIL-S-901D(NAVY). The test items consist of deflection at upper rate load test, dynamic stiffness, uniformity, static load-deflection(axial, transverse and longitudinal), drift test, fatigue test, and shock test. From these performance tests, it is confirmed that the two mounts have good performances based on military standards.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.648-655
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• 2005

The resilient mounts of a diesel engine installed onboard a ship should be designed for both static and dynamic loads. If possible, the resonance frequencies of the six rigid body modes of the installation and the flexible modes of the engine support structure should not lie within the engine operation range. In this paper a design criterion is proposed to evaluate an isolation system which involves the summation of dynamic forces transmitted through the resilient mounts and elastic potential energy index stored in the mounts. A case study is also presented in which a diesel engine generator, which had an elastic foundation and was mounted in a 5500 TEU container vessel, was studied both theoretically and experimentally. The theoretical analysis of the test model was performed by using a single mass 6 degree of freedom system. Actual measurements of mechanical vibration of the Engine and its foundation onboard were carried out, which showed the importance of including the flexibility of the engine support structure in the mode

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.3
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• pp.218-225
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• 2013

Vertically-launched missiles are supported as erected vertically in the vertical launching system of warship, and they should be mounted in the same way when vibration-tested. However, mounting missiles vertically makes a fixture, which is a supporting structure, bulky and heavy so requiring a high-performance exciter. Mounting missiles as laid down horizontally in a vibration test is economical regarding fixture manufacturing and exciter performance, but it makes test results incorrect because the different mounting direction has effects on the test results. A bending moment due to missiles' weight happens to missiles, and resilient mounts, which support missiles in the vertical launch system, deflect differently from the real situation because of the static deflection of these mounts due to missiles' weight. If the resilient mounts supporting missiles have nonlinear force-deflection characteristics, vibration test results become more different from the true results. This paper proposes to support missiles with an additional resilient mount such as a bunge code in order to solve those problems coming from mounting vertically-launched missiles as laid down horizontally in vibration tests. The proposed approach enables to obtain the same test results as in their actual mounting condition even though vertically-launched missiles are mounted in a different direction.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.4 s.109
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• pp.329-338
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• 2006

The resilient mounts of a diesel engine installed onboard a ship should be designed for both static and dynamic loads. If possible, the resonance frequencies of the six rigid body modes of the installation and the flexible modes of the engine support structure should not lie within the engine operation range. In this paper a design criterion is proposed to evaluate an isolation system which involves the summation of dynamic forces transmitted through the resilient mounts and elastic potential energy index stored in the mounts. A case study is also presented in which a diesel engine generator, which had an elastic foundation and was mounted in a 5500 TEU container vessel, was studied both theoretically and experimentally. The theoretical analysis of the test model was performed by using a single mass 6 degree of freedom system. Actual measurements of mechanical vibration of the engine and its foundation onboard were carried out, which showed the importance of including the flexibility of the engine support structure in the mode.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.2
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• pp.102-107
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• 2014

The engine excitation forces are considered as major vibration source for the forklift truck, especially in small class. Even though the current engine mounting system designs are acceptable for vibration isolation, the performance of the engine mounting system is still required for the tendency of light weight, higher power and driver's higher vibration requirement. In this paper vibration reduction technique of forklift engine which is supported on rubber mounts is presented. Based on the dynamic model of resilient engine mounting system, design evaluation program is established. The design optimization technique and evaluation method of system properties are discussed. Effects of optimal design are validated through comparison with test results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.787-791
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• 2013

The engine excitation forces are considered as major vibration source for the forklift truck, especially in small class. Even though the current engine mounting system designs are acceptable for vibration isolation, the performance of the engine mounting system is still required for the tendency of light weight, higher power and driver's higher vibration requirement. In this paper vibration reduction technique of forklift engine which is supported on rubber mounts is presented. Based on the dynamic model of resilient engine mounting system, design evaluation program is established. The design optimization technique and evaluation method of system properties are discussed. Effects of optimal design are validated through comparison with test results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1991.04a
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• pp.119-125
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• 1991

본 연구에서는 일반적인 6자유도의 비대칭 강체가 3방향 탄성계수를 갖는 마운트에 지지되어 있는 6장도계의 진동해석기법을 확립하고, 고유진동, 강 제진동응답 및 진동전달력해석을 위한 프로그램을 개발하였다. 아울러 실제 응용된 사례와 타종의 마운트를 적용한 결과를 비교함으로써 설계의 타당성 을 검증하였다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.381-386
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• 2004

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.3
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• pp.342-347
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• 2015

The launcher pod for missiles capable of carrying a range of different warheads has been designed to be mounted on the tracked vehicle of the hybrid weapon system (HWS). In the development of this launcher pod, its structure was designed to be resilient to damage caused by shock and vibration, as well as preventing assembly errors due to the spring-back of the main composite cover and interfacing parts. This study investigated the design of the newly developed launcher pod, with its hybrid composite-metal structure, through simulation and experiment. Both simulation and actual experiments showed that the structure of the launcher is resilient to vibration and shock. The launcher pod was also subjected to vibration and shock tests to verify its performance.