Vibration analysis of foam filled honeycomb sandwich panel – numerical study

Abstract

Honeycomb structures are widely used in transportation industries. Owing to their lightweight, high strength, damage tolerance and thermal resistance, they are extensively used as a solution to modern engineering problems in the vehicle structure’s design. Furthermore, lightweight polymeric foams can be exploited to improve mechanical properties of sandwich panels. Recently, foam filled honeycomb sandwich panels have been proposed in order to benefit from mechanical characteristics of both honeycomb cellular structure and polymeric foam in the core of the sandwich panel. Until now, most of the investigations were delved into the mechanical properties of the foam filled honeycomb sandwich panels; in plane crushing, out of plane impact and local indentation response of these panels were broadly discussed previously. On the other hand, since many vehicles’ failure are related to severe vibrations, clear understanding of foam filled honeycomb panels eigenvibration properties is vital. In this paper, vibration frequencies and mode shape of honeycomb sandwich panels with different cores are studied using numerical method. At the first step, elastic mechanical properties of polyurethane foams were determined by experimental tests, next a finite element model was developed by means of Abaqus software package. Parameters, such as first resonant frequency, mode shapes and influence of foams on local vibration of the honeycomb core were investigated.

Keywords:

• Honeycomb sandwich panel
• polyurethane foam
• finite element analysis
• modal analysis