Dynamic Response of Chiral Truss-core Assemblies

ABSTRACT: Periodic cellular configurations with negative Poisson's ratio have attracted the attention of several researchers because of their superior dynamic characteristics. Among the geometries with a negative Poisson's ratio, the chiral topology features localized deformed configurations when excited at one of its natural frequencies. This is of particular importance as resonance can be exploited to minimize the power required for the appearance of localized deformations, thus giving practicality to the concept. The particular nature of these deformed configurations and the authority provided by the chiral geometry suggest the application of the proposed structural configuration for the design of innovative lifting devices, such as helicopter rotor blades or airplane wings. The dynamic characteristics of chiral structures are here investigated through a numerical model and experimental investigations. The numerical formulation uses dynamic shape functions to accurately describe the behavior of the considered structural assembly over a wide frequency range. The model is used to predict frequency response functions, and to investigate the occurrence of localized deformations. Experimental tests are also performed to demonstrate the accuracy of the model and to illustrate the peculiarities of the behavior of the considered chiral structures.

[1]  Charles O’Neill,et al.  Low Reynolds Number Airfoils MAE 5233 , 2001 .

[2]  Kenneth E. Evans,et al.  The interpretation of the strain-dependent Poisson's ratio in auxetic polyethylene , 1997 .

[3]  A. Beltzer,et al.  Reexamination of dynamic problems of elasticity for negative Poisson’s ratio , 1988 .

[4]  Srinivasan Gopalakrishnan,et al.  A spectrally formulated finite element for wave propagation analysis in functionally graded beams , 2003 .

[5]  M. El‐Raheb,et al.  Frequency response of a two-dimensional trusslike periodic panel , 1997 .

[6]  Fabrizio Scarpa,et al.  Evaluation of hexagonal chiral structure for morphing airfoil concept , 2005 .

[7]  M. Ashby,et al.  The topological design of multifunctional cellular metals , 2001 .

[8]  Jamey Jacob,et al.  ACTIVE CONTROL OF SEPARATION ON A WING WITH CONFORMAL CAMBER , 2001 .

[9]  Massimo Ruzzene,et al.  Structural and Acoustics Behavior of Chiral Truss-Core Beams , 2004 .

[10]  John W. Hutchinson,et al.  Optimal truss plates , 2001 .

[11]  Massimo Ruzzene.  Vibration and sound radiation of sandwich beams with honeycomb truss core , 2004 .

[12]  R. Lakes.  Foam Structures with a Negative Poisson's Ratio , 1987, Science.

[13]  T. S. Lok,et al.  FREE VIBRATION OF CLAMPED ORTHOTROPIC SANDWICH PANEL , 2000 .

[14]  K. Wojciechowski.  Non-chiral, molecular model of negative Poisson ratio in two dimensions , 2003 .

[15]  K. Wojciechowski,et al.  Two-dimensional isotropic system with a negative poisson ratio , 1989 .

[16]  Massimo Ruzzene,et al.  Global and local linear buckling behavior of a chiral cellular structure , 2005 .

[17]  Ahmed K. Noor,et al.  Continuum Modeling for Repetitive Lattice Structures , 1988 .

[18]  M. S. Chandrasekhara,et al.  Design and development of a dynamically deforming leading edge airfoil for unsteady flow control , 1997, ICIASF'97 Record. International Congress on Instrumentation in Aerospace Simulation Facilities.

[19]  Michael Amitay,et al.  Aerodynamic control using synthetic jets , 2000 .

[20]  Roderic S. Lakes,et al.  Deformation mechanisms in negative Poisson's ratio materials: structural aspects , 1991 .

[21]  Y. Bar-Cohen,et al.  Electroactive polymers (EAP) as artificial muscles , 2002 .

[22]  James F. Doyle,et al.  Wave Propagation in Structures , 1989 .

[23]  Michael F. Ashby,et al.  The out-of-plane properties of honeycombs , 1992 .

[24]  R. Lakes,et al.  Properties of a chiral honeycomb with a poisson's ratio of — 1 , 1997 .

[25]  Fabrizio Scarpa,et al.  Theoretical characteristics of the vibration of sandwich plates with in-plane negative poisson's ratio values , 2000 .

[26]  M. Ashby,et al.  Cellular solids: Structure & properties , 1988 .