In-depth radiation absorption in pyrolysis models is commonly modeled with Beer’s law using a constant coefficient. This approximation neglects the effects of spectral variation coefficient, material emissions, and directional dependency penetrated thermal radiation. research aims to address importance these factors flammability analysis black poly(methyl methacrylate) (PMMA). Accordingly, mode...

Potential flow over rotating cylinder is usually solved by the singularity method. However,in this paper a mathematical solution is presented for this problem by direct solution of the Laplace’sequation. Flow over the cylinder was considered non-viscous. Neumann and Dirichlet boundaryconditions were used on the solid surfaces and in the infinity, respectively. Because of non-viscous flow,the La...

The finite volume method combines the advantage of the finite element method and the finite difference method, while overcoming their shortcomings. This paper describes the development of the finite volume method and the process of using finite volume method for fluid calculations. Finally, this paper introduces the process of using improved finite volume method for solving the flow equations o...

To enable the lattice-Boltzmann method (LBM) to account for temporally constant but spatially varying thermophysical properties, modifications must be made. Recently, many methods have emerged that can conjugate heat transfer (CHT). However, there still is a lack of information on possible physical property range regarding realistic properties. Therefore, two test cases were investigated gain f...

Abstract In the hydropower plants exposed to excessive sediment concentration, components of Francis turbines, especially regions Guide Vanes (GVs) and Runner (RVs) are severely eroded. The side-wall clearance between GV runner is present in these turbines separate rotating stationary components. height difference inlet outlet covers, introduced during fabrication or assembly process might play...

Laser polishing (LP) is an effective method to improve the surface quality of additively manufactured nickel-based alloy. In this paper, in-situ laser (ILP) experiment performed on selective melting (SLM) IN718 samples. The white light interferometer used test three-dimensional profile and roughness results show that as-SLMed samples by ILP improved. particular, decreased 33.5%. To reveal mecha...

The dendrite growth in casting and additive manufacturing is rather important related to the formation of some defects. However, quantitatively simulating dendrites with arbitrary crystallographic orientations 3-dimension(3D) still very challenging. In present work, we develop a multi-grid Cellular Automaton (CA) model for growth. this model, interfacial area further discretized into child grid...

The term “hydraulics” is concerned with the conveyance of water that can consist very simple processes to complex physical processes, such as flow in open rivers, pipes, nutrients/sediments, groundwater sea waves. study hydraulics primarily a mixture theory and experiments. Computational helpful quantify predict nature behavior. mathematical model backbone computational consists equations linea...

Ships sailing through cold regions frequently encounter floe ice fields. An air-bubble system that reduces friction between the hull and floes is thus considered useful for reduction of ice-induced resistance. In this study, a numerical analysis procedure based on coupled finite volume method (FVM) discrete element (DEM) proposed to simulate complicated hull-water-gas-ice interactions ice-going...

Volume free electron laser uses volume distributed feedback (VDFB), which can essentially reduce the threshold current of generation and provides the possibility of smooth frequency tuning. An undulator VFEL is considered.