Thermal-Hydraulics

  CFD Information

 

I

TH Home
CFD Information Home
CFD Forums
CFD Documents
CFD Interesting Stuff
CFD References
CFD Research
CFD Software
CFD Web Links
CFD Projects
CFD Special Topics
Ventilation
Computer Codes
Finite Element
Free Software
Heat Transfer
Hydrology
Materials Property
National Labs
Numerical Methods
RELAP5
Research
Simulations
Topics
Books
Math Information
Guide to Calculators
Guide to Arithmetic
Math History
Other Sites
Shopping
Computer Shopping
American Family
Computers
Genealogy
This site is dedicated to providing Computational Fluid Dynamics (CFD) up to date information.  The following sections provides significant insight into CFD.

If you've been solving stress problems using finite-element software, you'll eventually encounter a few that involve fluid flows. These situations are likely to require working with the FEA program's computational fluid dynamics (CFD) section. CFD was once the domain of Ph.D.s and supercomputers. But the hardware and software are so improved that a wider range of engineers now use it. "The guiding principles for getting accurate answers from a CFD program have not changed," says Ulises Gonzalez, a senior engineer for Pittsburgh-based Algor Inc. From his experience solving fluid problems, Gonzalez provides these observations and rules of thumb.

Fluid-flow problems fall into two categories: steady and unsteady. It is also important to note that some problems expected to be steady turn out to be oscillatory, and thus unsteady. CFD software packages generally use iterative methods to converge on the correct solution. Such methods are used to solve both steady and unsteady problems. In the solution of unsteady problems, time integration methods are used to advance the solution from one time-step to the next. In contrast, solutions to steady problems also use integration methods, but in what is called pseudo-time.

As an example of a steady problem, "Consider a fluid flowing through a cylindrical duct with a rubber orifice serving as a partial barrier to the flow," says Gonzalez. "This could be a biological application. Imagine a constant flow through this duct and how it deforms the orifice. But the question is, by how much?" he asks. Even this relatively simple problem involves a multiphysics approach. In this case, we must consider the coupled solutions of a CFD problem for the flow and a finite element stress analysis for the deformation of the orifice.

Consider the case in which the flow-rate through the duct is constant. CFD software can easily give a steady solution for the flow once the shape of the orifice is specified. But the shape is still in question. The first step in the solution to this multiphysics problem is to obtain the flow for the case of an undeformed, flat orifice.

"This first CFD solution can be used to obtain the pressure that the fluid causes on the flexible orifice. This pressure is subsequently used by the FEA portion to obtain the deformed shape of the orifice," says Gonzalez. Now we consider how the change in the orifice's shape affects the flow. "The orifice is now a curved surface with a hole. So the CFD solution using the new deformed orifice produces different pressure values, which will consequently result in yet another shape for the orifice," he says. Note how it appears that we are solving the transient problem of a moving orifice. But, instead, we are solving a steady problem in pseudo-time. When new pressures don't match those from the previous pseudo-time-step, we continue the process. "When they match to within an acceptable tolerance, the job is done," he says.

Oscillations in fluids produce more difficult problems. "Remember the Tacoma Narrows bridge catastrophe?" asks Gonzalez. "The wind speed was constant, yet the bridge kept oscillating. You might think it would get pushed downwind and stay there, like a sail. But it oscillated back and forth." Actually, the bridge was shedding unseen vortices in a periodic fashion. This subtle periodic flow caused the poorly designed bridge to oscillate at its natural frequencies until it collapsed.   (More from FindArticles.com)

 

Some of the sites given below are recommended by us:

bulletCFD Review  provides news and articles about CFD and the CFD software industry. The site is designed to foster user interaction through newsgroup like forums. Post your question on CFD Review and have our expert readers from a wide variety of CFD backgrounds answer your question! This valuable resource is provided free of charge to the CFD community.

 

bulletArticles Related to CFD

 

bulletCFD at Cranfield Computational Fluid Dynamics (CFD) has grown from a mathematical curiosity to become an essential tool in almost every branch of fluid dynamics, from aerospace propulsion to weather prediction. This is mirrored by the CFD activities at Cranfield, where individual research programmes together embrace a broad portfolio of research and teaching across the University.  

 

bulletSolutions at Fluent  Almost every industry that involves advanced engineering uses CFD. Its use is rapidly expanding, and more engineers use Fluent's CFD software worldwide than any other technology.

 

bulletMIT Fluid Dynamics Research Laboratory
The Fluid Dynamics Research Lab (FDRL) at MIT has a distinguished history, dating back to 1950's with a research background that balances theory, experiment and computation in supersonic flow, aerodynamic noise, hydyodynamic stability, and aeroelasticity.

 

bulletU. Louisville Mechanical Engineering Department  The Computational Fluid Dynamics (CFD) Laboratory was established in 1997 by Prof. Timothy E. Dowling, an Associate Professor of Mechanical Engineering. Professor Dowling's research specialty is numerically modeling the atmospheric dynamics and...... 

 

bulletCFD Online - collection of links, jobs database, and discussion forum for Computational Fluid Dynamics.

 

bulletCFD WWW home pages list  The following is a list of WWW home pages that pertain to computational fluid dynamics. This list was originally compiled by Robert Chong (chong@infinet.com), and is now being maintained by Wayne Christopher (wayne@icemcfd.com). Please send all suggestions and updates to Wayne.

 

bulletITSC Fluids Movie Archive - animations produced by CFD codes of either classical, interesting or familiar fluid & thermal processes.

 

bulletAdvanced Computational Engineering (ACE) Lab  Advanced Computational Engineering Lab About the Lab Publications 

 

 

bulletCFD codes list - free software
CFD codes list - free software UIFlow Foil 1.0.2 PPM -- Piecewise Parabolic Method (DE and LR versions) General Relativity NCSA group (black hole evolution) NACA airfoils College of Marine Studies (sci.geo.fluids models) Ocean models (MOM, POM, POP).

bulletCFD codes list - commercial products
CFD codes list - commercial products ACRi ARSoftware (TEP: a combustion analysis tool for windows) COSMIC NASA Fluent Inc. (Fluent/V4, Fluent/UNS, Rampant, Nekton) Flowtech Int. AB (SHIPFLOW: analysis of flow around ships) Fluid Dynamics International.

bulletCFD codes list - shareware products
CFD codes list - shareware products SSIIM (3D water and sediment flow) LCA codes for astrophysical simulation and visualization PHOENICS/CHAM shareware (multi-phase flow, N-S, combustion) NASA LeRC (LPDF2D) Collection of CFD codes for ship design So

bulletCFD Codes List
CFD Codes List

bulletCFD codes list - related software
[an error occurred while processing this directive] CFD codes list - related software Harmonic Software Inc. (O-Matrix) Radiative Transfer Mechanical Analysis Harmonic Software Inc. From Harmonic Software / harmonic@omatrix.com Date: Wed, 13 Nov.

 

bulletUseful WWW Servers for CFD-Related Codes
Useful CFD Sites CFD Online FAST Home Page Unsteady Flow Analysis Toolkit (UFAT) EPIC (EPCC Interactive Courseware) NCSA CFD-RuG CFD used in River and Hydropower Engineering CFD-Stilling Basil Model Study CFD-Cranfield University -UK NASA Thesaurus.

 

bulletMathematik
CFD CFD Resources Online CFD home pages list CFD codes list (Germany) CFD codes list (USA) CFD codes list (Italy) Computational Fluid Dynamics HomePage (Cranfield University -UK) CFD Resources Online Applications Directory(Silicon Graphics): 

 

Companies

 
bulletAdapco-STAR-CD is the CFD technology leader for fluid flow analysis in the automotive, aerospace, turbo-machinery, chemical process and power generation industries.

bulletAEA Technolgy-AEA Technology Engineering Software has announced major enhancements to its Computational Fluid Dynamics (CFD) modeling capability for process and chemical engineers, with the release of CFX-4.4.The software allows the highly complex fluid dynamic, heat transfer and chemical processes that occur in mixing vessels to be predicted accurately and efficiently.
bulletAeroSoft-AeroSoft develops and markets state-of-the-art,
computational fluid dynamics analysis and design software.  Announcing the imminent release of GASP Version 4 For a sneak preview of the many exciting new features, click on the image below

 

bulletCEI-APEX, N.C., February 16, 2001 Free copies of EnLiten Basic and EnVideo Basic are now available for downloading. The two new products enable engineering and research organizations to use the Internet and corporate intranets to share high-end visualizations throughout the enterprise.  EnLiten and EnVideo work in conjunction with EnSight and EnSight Gold, used by 350 organizations worldwide to analyze, visualize and communicate computer-aided engineering and scientific research results.

 

bulletCFDRC  CFDRC's goal is to Develop and Effectively transfer CFD and Related Technologies to Industry.  Since its inception in 1987, the company has grown steadily with highly-qualified and motivated individuals.  Presently, CFDRC has over 120 employees, performs over $10 million a year in contracts, and licenses its software to over 300 organizations worldwide.
bulletComputational Dynamics  The CD adapco Group, is one of the world's major developers of software and problem specific engineering methodology for industrial CFD analysis.  STAR-CD is the CFD technology leader for fluid flow analysis in the automotive, aerospace, turbo-machinery, chemical process and power generation industries.
bulletExa  Exa Corporation develops and markets PowerFLOW, a fluid flow simulation software for engineers to analyze complex fluid flow problems. The company's products, based on Exa's patented DIGITAL PHYSICS technology, are marketed to engineers worldwide.
bulletICEM CFD  ICEM CFD Engineering, a subsidiary of ANSYS, Inc., develops and markets software for pre- and post-processing of engineering applications such as computational fluid dynamics and structural analysis. Our major products include ICEM CFD, the leading software for 3-D grid generation for CFD and other engineering applications, and Icepak, an electronics cooling simulation system created in collaboration with Fluent Inc..
bulletISGG and Links
bulletIntelligent Light  If your CFD post processor isn't delivering all the information you need for each solution, you're not getting the whole story. When vital features are missed the result can be additional, costly solver runs. Worse yet, it can affect the decisions people make based on the entire CFD process.
bulletFidap  With its wealth of physical models and efficient solution methods, FIDAP is the flow modeling tool of choice for applications such as polymer processing, thin film coating, biomedical, semiconductor crystal growth, metallurgy, glass processing and related fields. Based on the finite element method, FIDAP offers complete mesh flexibility and robust and efficient calculations. It is available for UNIX and Windows/NT workstations and is optimized for parallel processing.
bulletFluent  We offer flow and heat transfer modeling software suited to a wide range of applications. We provide unlimited, industry-specific technical support to our users. World-class CFD consulting is also available.
bulletNumeca
bulletPointwise  

Pointwise, Inc. is solving the top problem facing engineering analysts today: grid generation and pre-processing for CFD.  Our solutions to this problem consist of products and services centered around the Gridgen software.  Gridgen is being used right now by scientists and engineers to prepare geometry data for computer simulations of fluid flow.  Gridgen accomplishes this by serving as the enabling software bridge that connects computer aided design (CAD) software and analysis software such as computational fluid dynamics (CFD) and finite element analysis (FEA).

bulletProgram Development Corp.
Tecplot  We are the leading provider of products and services for Grid Generation. Our mission is to provide the highest quality, the most versatile, and user-friendly grid generation software available for computational fluid dynamics and structural analyses.

Information

bulletCFD Forums
bulletDocuments
bullet Interesting Stuff
bulletProjects
bullet References
bullet Research
bulletSpecial Topics
bulletSoftware
bulletWeb Links
 
 

For comments send an email to: SiteManager@i-edainc.com
Copyright 2001-2002 EDA, Inc.. All rights reserved.

Revised: November 03, 2003 .