Larry W. Byrd

Bio: Larry W. Byrd is an academic researcher from Wright-Patterson Air Force Base. The author has contributed to research in topics: Ceramic matrix composite & Heat transfer. The author has an hindex of 13, co-authored 35 publications receiving 1340 citations. Previous affiliations of Larry W. Byrd include Missouri University of Science and Technology.

Modeling and Analysis of Functionally Graded Materials and Structures

Abstract: This paper presents a review of the principal developments in functionally graded materials (FGMs) with an emphasis on the recent work published since 2000. Diverse areas relevant to various aspects of theory and applications of FGM are reflected in this paper. They include homogenization of particulate FGM, heat transfer issues, stress, stability and dynamic analyses, testing, manufacturing and design, applications, and fracture. The critical areas where further research is needed for a successful implementation of FGM in design are outlined in the conclusions. DOI: 10.1115/1.2777164

Effectiveness of z-pins in preventing delamination of co-cured composite joints on the example of a double cantilever test

Abstract: The effectiveness of z-pins in co-cured joints is illustrated on the model of a composite double cantilever beam (DCB) subject to a standard fracture toughness test. A comprehensive solution is presented in the paper accounting for a broad spectrum of issues that affect the problem. They include the accurate evaluation of the rotational constraint provided by the intact section of DCB, possible transverse shear deformation in the delaminated section, and effects of uniform and nonuniform temperature on the response. A simple criterion for the effectiveness of z-pins in co-cured joint is introduced and its application is illustrated on numerous examples. As follows from the analysis, z-pinning is an effective method of enhancing delamination resistance of composite joints. Even a very small volume fraction of z-pins (less than 1.5%) may arrest delamination in co-cured composite joints.

Matrix cracking in transverse layers of cross-ply beams subjected to bending and its effect on vibration frequencies

Abstract: The solution for the matrix crack distribution in transverse layers of a cross-ply beam subjected to bending is developed based on the model of Han and Hahn (Compos Sci Technol 35 (1989) 377). This solution accounts for a bimodulus-type of the material response. As a result, it is possible to predict the extent and distribution of matrix cracks as well as the stiffness distribution in the beam subjected to bending, accounting for residual thermal stresses. The results of the solution of the bending problem are employed in the analysis of free and forced vibrations of a cross-ply beam with matrix cracks in transverse layers. The solution differs from the case of vibrations of an intact beam due to a difference in response of damaged layers under tension and compression. The results are shown for the natural frequency of a representative ceramic matrix composite (CMC) beam.

Effects of thermal dispersion and stratification on combined convection on a vertical surface embedded in a porous medium

Abstract: The effects of thermal dispersion and thermal stratification on mixed convection about a vertical surface in a porous medium are studied. The conservation equations that govern the problem are reduced to a system of nonlinear ordinary differential equations. The resulting equations are solved on the basis of the local similarity approximation. The results indicate that both dispersion and stratification effects have considerable influence on the heat transfer rate.

Introduction to the Finite Element Method

Abstract: This chapter introduces the finite element method (FEM) as a tool for solution of classical electromagnetic problems. Although we discuss the main points in the application of the finite element method to electromagnetic design, including formulation and implementation, those who seek deeper understanding of the finite element method should consult some of the works listed in the bibliography section.

Convection Heat Transfer

Abstract: Geometry: shape, size, aspect ratio and orientation Flow Type: forced, natural, laminar, turbulent, internal, external Boundary: isothermal (Tw = constant) or isoflux (q̇w = constant) Fluid Type: viscous oil, water, gases or liquid metals Properties: all properties determined at film temperature Tf = (Tw + T∞)/2 Note: ρ and ν ∝ 1/Patm ⇒ see Q12-40 density: ρ ((kg/m) specific heat: Cp (J/kg ·K) dynamic viscosity: μ, (N · s/m) kinematic viscosity: ν ≡ μ/ρ (m/s) thermal conductivity: k, (W/m ·K) thermal diffusivity: α, ≡ k/(ρ · Cp) (m/s) Prandtl number: Pr, ≡ ν/α (−−) volumetric compressibility: β, (1/K)