Experimental Investigation of Thermal Modal Characteristics for a Ship’s Foundation under 300°C

Abstract

How to further reduce vibration and noise is a major challenge for modern ship design. High-temperature environment will significantly influence the mechanical properties (such as elastic modulus and stiffness) of the ship’s foundation. These properties will have a serious impact on the inherent vibration characteristics of the foundation. In this paper, a simplified foundation is taken as the research object, and a thermal-vibration joint test system is developed for investigating the thermal modal characteristics of the foundation under different temperatures. The joint test system consists of a transient aerodynamic heating environment simulation system and a vibration excitation and acquisition system. Finite element method (FEM) is used to analyze the distribution of thermal fields. The influence of the ceramic rods and the different ambient temperatures on the modal characteristics of the foundation is studied. The results indicate that the effect of ceramic rods on the modal characteristic of the foundation is negligible. The results also show that the greater the vibration response amplitude is as the temperature increases and the first-order natural frequency does not change, the smaller the second-order natural frequency and the damping ratio will become smaller. The variation of natural frequency and damping ratio of the foundation under different temperature conditions can provide a reliable experimental basis for the design of the vibration and noise reduction of the ship’s foundation in the thermal-vibration environment.

Research on Vibration Reduction Design of Foundation with Entangled Metallic Wire Material under High Temperature

“…ermal-Vibration Joint Test System. In order to complete the experiment at a high temperature, a thermal-vibration joint test system is developed by our team [33]. e structural block diagram of the system is shown in Figure 16.…”

Mechanical behavior and improved model of multi-strand entangled metallic wire material

“…Entangled metallic wire material (EMWM), which is also called metal rubber (MR), plays a vital role as a new type of damping material in reducing vibration in the harsh environment, such as high or low temperature [3,4], impact [5,6], fatigue loading cycles [7]. It has been widely applied in various fields such as aero-engines [8], electromagnetic engines [9], and equipment foundation [10].…”

Experimental Research on Vibration Reduction of Cantilever Structure in High‐Temperature Environments

“…e methods for constructing a simulated thermal environment are airflow heating and radiant heating [14]. Radiant heating has the advantages of long heating time, strong heating capacity, multitemperature zone control, etc.…”

“…us, the radiant heating method was widely used in thermovibration joint test [14,15]. Ding et al set up a transient aerodynamic heating environment simulation system by using two quartz lamp arrays and investigated the thermal modal characteristics of a ship's foundation under 300°C.…”

“…Ding et al set up a transient aerodynamic heating environment simulation system by using two quartz lamp arrays and investigated the thermal modal characteristics of a ship's foundation under 300°C. To reduce costs and avoid signal compensation, ceramic rods are often used to induce the vibration response signal of the structure at high temperature to room temperature for data collection [14,15]. e main aim of this paper is to investigate the vibration reduction of cantilever structure by adding entangled metallic wire material core in a wide ambient temperature from room temperature (25°C) to 500°C.…”