The main goal of this study is to examine the possibility of using detailed three-dimensional simulations of transport of momentum, energy, and mass in horizontal single-wafer epitaxial silicon reactors in conjunction with relatively simple kinetic models to describe the reactor's performance over the entire range of operating conditions. As the SiHCl 3 -H 2 system is a widely used precursor for epitaxial silicon deposition in industrial applications, we have chosen to focus our model development on this system. In the development of the model we have considered the dependence of the gas properties on the gas composition as well as on the temperature. In addition, mass transport due to thermal diffusion has been considered. The accuracy of the simulation model has been examined by comparing the predicted silicon deposition rates and profiles in two commercial chemical vapor deposition (CVD) reactors with the experimentally measured values. A comparison of simulation and experimental results has indicated that a detailed transport model in conjunction with a Langmuir-Hinshelwood type kinetic model for silicon deposition accurately describes the epitaxial silicon deposition rate and deposition profile. In turn, this lumped reaction kinetic model has been used for optimization of commercially available horizontal CVD reactors for epitaxial deposition of silicon. Figure 1. Schematic representation of a typical horizontal CVD reactor.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.194.20.173 Downloaded on 2015-06-17 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.194.20.173 Downloaded on 2015-06-17 to IP

Injected pultrusion (IP) is an attractive process for high volume, high performance, and low cost manufacture of continuous fiber reinforced polymer matrix composites. In this work we focus our attention on development of a computer simulation model for the IP process. First, the governing equations for conservation of mass, momentum, and energy are developed using a local volume averaging approach. In turn, a computer simulation model of the IP process is developed using finite element/control volume (FE/CV) and finite difference techniques. Specifically, the equation of continuity and conservation of momentum are solved in 2-D using a Galerkin FE/CV technique. The energy and chemical species balance equations are solved in 3-D. where slnarnhn ' e upwind Petrov-Galerkin (SUPG) or slnarnhn ' e upwind (Sv) FE/CV are used to discretize the equations in two dimensions while finite differences have been used in the third dimension. The chemical species balance equation is solved in the Lagrangian frame of reference using finite differences. Different numerical formulations (Galerkin, , SU, and SUPG) are used to solve a number of benchmark problems to determine the best numerical formulation. It is shown that for coarse discretization, Streamline Upwind methods perform consistently better than the other methods. However, for refined meshes, the Lagrangian method produces the best solution for a given CPU time. Also, using the simulation model, the effect of fiber pull speed, reinforcement anistropy, and taper of the die on the quality of the product is studied. It is shown that the simulation model can be effectively used to design the die geometry as well as to optimize the operating conditions for a given product. *

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