A Study on the Hybrid Mount against Vibration and Shock for Naval Ships

Abstract

In naval ships, some methods or devices are acquired both to cut off the transmission of vibration from shipboard machineries and to protect them from external shock loading. One of the approaches is to install the passive mountings between machinery and a flexible supporting structure. More advanced performance has become necessary recently so far as at high frequencies in order to retain the stealth function of certain types of naval vessels.For the purpose of this research, a novel hybrid mount for shipboard machinery installed on naval ships was developed. The mount is combined with a rubber mount and piezostack actuators. The rubber mount is one of the most popular and effective passive mounts to have been applied to various vibration systems to date. The piezostack actuator is featured by a fast response time, small displacement and low power consumption. Through a series of experimental tests conducted in accordance with MIL-M-17185A(SHIPS), MIL-M-17508F(SH), and MIL-S-901D which are US military specifications related to the performance requirements of the mount, it has been confirmed that the hybrid mount shows more effective performance for use in naval ships.

An inertia-type hybrid mount combining a rubber mount and a piezostack actuator for naval shipboard equipment

“…The hybrid mount proposed in this study consists of passive and active elements, with a rubber element serving as the passive element and a piezostack element serving as the active one, following the extended line of the previous research (Moon et al, 2010). The hybrid mount developed in the previous research was composed of a rubber element and two piezostack elements, which were serially connected as shown in Fig.…”

“…From the model, the governing equations of motion can be derived as follows: inertia-type hybrid mount. hybrid mount (Moon et al, 2010).…”

“…The military performance tests included the following: resonant frequency, deflection at rated load, quality of the rubber to metal bond, strength test in the axial direction, strength test in the radial direction, drift test, fatigue test, and shock test. Since these testing items are the same as those used in the previous research (Moon et al, 2010), the test results were only addressed briefly in this paper. Fig.…”

“…The hybrid type, which can be activated by various types of actuators including hydraulic actuators (Turnip et al, 2009), electromagnetic actuators (Howard et al, 2000;Lee and Lee, 2009) or piezoelectric actuators (Kamada et al, 1997;Choi et al, 2004;Nguyen et al, 2009), is utilized to improve the isolation performance of the passive type. In our previous research (Moon et al, 2010;Nguyen et al, 2008), a 100 kg-class hybrid mount-combined with a rubber mount and piezostack actuators -was developed for use with various items of shipboard machinery installed on naval ships.…”

In-Structure Shock of Surface Structures: A Theoretical Approach

“…Small scale test is conducted to validate the theoretical prediction of in-structure shock of underground structures [11]. Hybrid mounting system is tested [12]. In early years, instructure shock of surface structures is of minor significance since whether the structure can survive the explosion is the major concern.…”