Aerodynamic Heating with Turbulent Flow

This paper discusses approximate methods which have been used to calculate turbulent heating rates for a  flat plate case. Simple approximate methods are needed for a practical engineering analysis because of their short computing-time. Although solutions by computational  fluid dynamics (CFD) would give the most precise prediction, CFD is still costly in terms of its long computing-time. The paper especially deals with turbulent flows. The matter of turbulent flows. is critical for aerodynamic heating since the heating rate in turbulent  flows are much higher than that in laminar  flows. As shall be seen, the methods for turbulent heating are...

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A Triangular Grid Generation by Cauchy Riemann Equations

In this article, we present a method that generates a smooth triangular grid around an object. A grid in a two-dimensional physical space will be generated by solving Cauchy-Riemann equations in the physical space by treating the grid as unknown. The method is in principle the same as the elliptic grid generation method. The grid generation by elliptic partial differential equations has been a popular technique for quite sometime. The main advantage of the method is the fact that the resulting grid is smooth and orthogonal which are very important to the accuracy of the numerical solution. The idea...

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Solving a Combustion Simulation for a Sector

In this tutorial a complete Direct injection (DI) compression ignition (CI) engine geometry is transformed into 60° sector in-order to reduce mesh size and solution time. Detailed boundary conditions are as shown in the  Figure 3.1: Problem Schematic (p. 107). Sector simulation is started at intake valve Closing (IVC) with initial conditions as 3.45 bar and 404 K, species mass fraction of O2=0.1369, N2=0.7473, CO2=0.0789,H2O=0.0369. n-heptane (nc7h16) is used as surrogate for diesel fuel and is injected 8 degrees before compression ( T op Dead Center). Engine rpm is increased from 1500 rpm to 2000 rpm and its effect...

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Derivation of Osher’s Riemann Solver

All numerical fluxes are functions of the left and right states (and possibly dt and dx). Learn how those famous fluxes can be implemented, or just use them to see how they work for various shock-tube problems. Included are Lax-Friedrichs, Richtmyer, MacCormack, Steger-Warming, Van Leer, AUSM, Zha-Bilgen, Godunov, Osher, Roe, Rusanov, HLL, HLLL, AUFS flux functions. Free Download PDF (Derivation) + Code (F90) Free Download Code +...

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Tecplot Chorus

Tecplot Chorus is used for trade studies to help you compare collections of CFD simulations while evaluating overall system performance. Tecplot Chorus includes our most recent version of Tecplot 360 EX. Overview Design Space Visualization & Analysis Tecplot Chorus helps you run and generate many simulation or test data sets. The most common applications are: Optimizing your designs. Developing aero databases. Predicting performance over the operating envelope. Investigating engineering problems. In these scenarios, you need to manage your solution data, discover the trends and anomalies in output variables, and understand the underlying physics that cause these variations. Based on...

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Comsol Multiphysics 5.2.1

COMSOL provides simulation software for product design and research to technical enterprises, research labs, and universities through 18 offices and a distributor network throughout the world. Its flagship product, COMSOL Multiphysics, is a software environment for modeling and simulating any physics-based system. A particular strength is its ability to account for coupled or multiphysics phenomena. Add-on products expand the simulation platform for electrical, mechanical, fluid flow, and chemical applications. Interfacing tools enable the integration of COMSOL Multiphysics simulation with all major technical computing and CAD tools on the CAE market. COMSOL, the leading provider of multiphysics modeling and simulation...

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Flow3D 11.0.4

FLOW–3D, a CFD software developed by Flow Science, enables highly-accurate simulations of free-surface flows using TruVOF and FAVOR techniques. FLOW-3D is a powerful and highly-accurate CFD software that gives  engineers valuable insight into many physical flow processes. With  special capabilities for accurately predicting free-surface flows, FLOW-3D is the ideal CFD software to use in your design phase as well as in improving production processes. MESHING FLOW-3D uses an approach to gridding that combines the advantages  of simple rectangular grids with the flexibility of deformed, body-fitted grids. Fixed grids of rectangular control elements are simple to generate and possess many...

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