This paper reviews an approach to design using Genetic Algorithms as applied to the domain of composite material structures. We first discuss the concept of a Genetic Algorithm (GA) and the role it can play in design, namely as an evolutionary search optimizer based on simulation results. We then discuss the composite structure design problem and how GA’s can be used for design in this domain. ...

Poor wetting leads to underperforming composite properties and has been a major obstacle in implementing low cost carbon fibers in SMC parts. The objective of this project is to solve the technical challenge of poor carbon fiber wet-through during Sheet Molding Composite (SMC) process. Continental Structural Plastics (CSP) partnered with ORNL to develop a new sizing technique called Point Sizin...

Mathematical models, for the stress analysis of symmetric multidirectional double cantilever beam DCB specimen using classical beam theory, first and higher-order shear deformation beam theories, have been developed to determine the Mode I strain energy release rate SERR for symmetric multidirectional composites. The SERR has been calculated using the compliance approach. In the present study, ...

Here we propose a cone-beam composite-circling mode to solve the quasi-short object problem, which is to reconstruct a short portion of a long object from longitudinally truncated cone-beam data involving the short object. In contrast to the saddle curve cone-beam scanning, the proposed scanning mode requires that the X-ray focal spot undergoes a circular motion in a plane facing the short obje...

We suggest a novel type of composite spatial optical soliton created by a coherent vortex beam guiding a partially incoherent light beam in a self-focusing nonlinear medium. We show that the incoherence of the guided mode may enhance, rather than suppress, the vortex azimuthal instability, and we also demonstrate strong destabilization of dipole-mode solitons by partially incoherent light.

Mode II delamination toughness of z-pin reinforced composite laminates is investigated using finite element (FE) method. The z-pin pullout process is simulated by the deformation and breakage of non-linear springs. A critical shear stress criterion based on linear elastic fracture mechanics is used to simulate crack growth in an end-notched-flexure (ENF) beam made of z-pinned laminates. The mod...

Aeroelastic instabilities are an important factor in the design of modern high-speed, flexible aircraft. The current trend is toward the creative use of composites to delay these instabilities. To obtain an optimum design, an accurate as well as efficient model is required. As a first step towards this goal, aeroelastic analysis is carried out for a swept composite box beam, using a linear stru...

In the present study, fuzzy control of vibration of a hybrid smart composite beam actuated by electro-rheological fluids (ERF) and piezoceramics actuators is investigated. A carbon fiber reinforced plastics (CFRP) cantilevered beam containing ERF with bonded piezoceramics is prepared and vibrated forcibly with sinusoidal external excitation. Fuzzy model of controlled element containing two actu...

Commercially available CdSe/ZnS and PbSe colloidal semiconductor quantum dots were employed to produce both an electron beam sensitive poly methyl methacrylate PMMA -quantum-dot QD positive composite via a prepolymerization processing and an electron beam and ultraviolet UV light sensitive SU-8-QD negative composite via a direct dispersion procedure. Compared to the QDs in the original colloida...

This paper deals with a dynamical inverse problem for a composite beam formed by two connected beams. The vibrations of the composite beam are governed by a differential system where a coupling takes place between longitudinal and bending motions. In this paper, we neglect bending motions and we only deal with the longitudinal motions. These motions are governed by a two-by-two second order sys...