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عنوان فارسی مقاله:
تاثیر طبیعت بر رفتار هسته ای صوتی ارتعاشی سازه ساندویچ هوافضا
عنوان انگلیسی مقاله:
Influence of nature of core on vibro acoustic behavior of sandwich aerospace structures
سال انتشار : 2016
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مقدمه انگلیسی مقاله:
1. Introduction
Sandwich panels are most commonly used as structural member in aerospace industries due to their high stiffness to weight ratio compared to conventional metallic and laminated composite structural members. The property of high stiffness to weight ratio leads to efficient transmission and radiation of acoustic noise [1]. Mellert et al. [2] studied experimentally the impact of sound and vibration on health, travel comfort and performance of flight attendants and pilots. Their results revealed that noise level has significant effect on various symptoms and health indices, especially when the level increases with time of work. Sandwich panel is made up of stiff top and bottom layer separated by a relatively soft core. The core can be of any material or architecture but four types are most generally used namely: (a) truss or corrugated core, (b) web core, (c) foam or solid core, (d) honeycomb core as shown in Fig. 1 for the above said applications [3]. Polymeric foam core has been replaced by aluminium sandwich structures with honey comb core and foam core [4,5]. The fuselage structure of passenger aircraft along with its mechanical duties has also to protect passengers against excessive noise and thermal constraints in the different flight phases [6]. A fuselage section analysed by Tooren and Krakers [6] consists of a ‘Z’ and ‘C’ stiffened sandwich panels. They optimised the stiffened structures for minimum weight subjected to mechanical, acoustical and thermal constraints. Sandwich panels are complex three dimensional thin walled structures for which numerical method is the most commonly employed method to analyse the dynamic behaviour of thin walled sandwich panels with different types of core geometries [7]. In order to analyse a sandwich panel numerically, both three dimensional finite element model (FEM) and its equivalent two dimensional FEM can be used. There are three ways to model a sandwich panel: (i) full solid modelling, (ii) shell modelling, and (iii) mixed modelling [8]. So, it is very important to select carefully which element to use. A 3D model requires high pre-processing time, is highly expensive and also it often leads to numerical ill conditioning [9]. Whereas a sandwich structure analysed by using its equivalent 2D FEM model avoids high preprocessing time and reduces numerical error to a greater extent [8]. Over all, the computational effort is significantly reduced when using the equivalent 2D FEM model [8]. Accuracy of the results obtained in a commercial FE software greatly depends on the equivalent elastic constants used. Libove and Hubka [10] derived the elastic constants for sandwich panels with a continuous corrugated core. Lok and Cheng [11] derived the equivalent elastic properties of a truss core sandwich panel and compared the maximum deflection for cellular, trapezoid and triangular core with zed core and corrugated core sandwich panels using 2D model and verified the result with 3D model. Fung et al. [12] presented elastic properties of z-core sandwich panel by comparing the behaviour of a unit z-core sandwich panel with that of a thick plate. Lok and Cheng [13] investigated the free vibration of clamped truss core sandwich panel. They have used equivalent stiffness properties of the sandwich panel, to find out the free and forced vibration response. The honeycomb sandwich plate is applied widely in the modern spacecraft structure design [14]. Boudjemai et al. [15] performed a numerical study on free vibration response of honeycomb panels used in the satellites structural design. They also analysed the effect of its design parameters using equivalent plate theory.
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کلمات کلیدی:
[PDF]Vibro-acoustic characteristics of TorHex honeycomb sandwich panels ... https://lirias.kuleuven.be/bitstream/123456789/269786/1/TRA2010_MVivolo.pdf by M Vivolo - 2010 - Cited by 1 - Related articles order to enhance their vibro-acoustic behaviour (Spilios E. Makris, 1986; ... Figure 1 Sample of a TorHex sandwich panel with faces of PP/natural fibres ... and at the structural responses, the effects coming from the core presence can be easily. Sound transmission loss characteristics of sandwich aircraft panels ... journals.sagepub.com/doi/abs/10.1177/1099636216652580 by MP Arunkumar - 2017 - Cited by 2 - Related articles Jun 12, 2016 - ... of sandwich aircraft panels: Influence of nature of core ... Elastic stiffness properties and behavior of truss-core sandwich panel. ... Vibro-acoustic response and sound transmission loss analysis of functionally graded plates. Vibro-acoustic response of sandwich plates with functionally graded ... link.springer.com/article/10.1007/s00707-015-1513-1 by N Chandra - Cited by 1 - Related articles Dec 21, 2015 - This paper presents the vibro-acoustic modeling and analysis of sandwich ... The vibration parameters in terms of natural frequencies, plate ... A comprehensive study of the influence of core thickness on vibro-acoustic performance is .... Kirugulige M.S., Kitey R., Tippur H.V.: Dynamic fracture behavior of ... M. P. ArunKumar - Google Scholar Citations scholar.google.co.in/citations?user=0yK6gGMAAAAJ&hl=en Influence of nature of core on vibro acoustic behavior of sandwich aerospace structures. MP Arunkumar, J Pitchaimani, KV Gangadharan, MCL Babu. Aerospace ... Researchers from National Institute of Technology Report Findings in ... https://www.newsrx.com/Butter/#!Search:a=12482377&q... Researchers from National Institute of Technology Report Findings in Aerospace (Influence of nature of core on vibro acoustic behavior of sandwich aerospace ...
