Reddit reviews Computational Fluid Dynamics
We found 11 Reddit comments about Computational Fluid Dynamics. Here are the top ones, ranked by their Reddit score.
Reddit reviews Computational Fluid DynamicsWe found 11 Reddit comments about Computational Fluid Dynamics. Here are the top ones, ranked by their Reddit score.
>I'm not sure what kinds of other heavy scientific computing you've done, but CFD is a very difficult field and takes years to understand.
CFD isn't this difficult.
On one side you have partial differential equations (PDEs) describing fluid flow. On the other side you have numerical methods used to solve those PDEs. Put the two together, implement it in code, and you get a rudimentary CFD simulation. For CS students, who typically already have knowledge of numerical methods, coding one of these basic simulations can be done within a semester's worth of focused effort. Venturing into finer, more complex domains and trying to model more advanced flow phenomenons do indeed require years of study, but a beginner -- a 3rd year CS undergrad of all people -- has no need to deal with that stuff when all they want to accomplish is to get their feet wet with the inner workings of the simplest CFD simulation.
So let's not intimidate the poor kid and not oversell the profession. A lot of people love pretending like this stuff is black magic, presumably because it promotes job security, but it just isn't. There are lots of people doing CFD that come from CS and Applied Math backgrounds instead of Engineering or Physics. They all started somewhere. So can the OP.
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@ /u/AnotherBrownBike
Khan Academy Physics, Fluid Dynamics lectures are your best friend in this.
I would recommend that you start with getting a decent physical understanding of incompressible (also called divergence-free) advection-diffusion equation. This is a simple PDE that describes how particles (or other quantities like energy) are transferred inside a physical system due to the process of diffusion and advection (aka convection). Solving this equation using a numerical solution method for PDEs (such as finite volume or finite element) will allow you to practice the fundamental underpinnings of a CFD code.
Finite Volume methods are more popular in CFD than finite element methods, because they're mathematically easier for people who have a robust understanding of fluid mechanics. That's not going to be the case for you, because you're not studying fluids academically. I would recommend that you focus on finite element methods instead. These are mathematically more challenging -- using them with fluid PDEs require stabilization terms (like SUPG or GLS) to prevent the solution from oscillating. However, the application of finite element methods to fluid PDEs require essentially no knowledge of the physics behind the PDE. It's pure mathematics, and you as a CS student should be well equipped to handle this.
If you're not familiar with finite element methods for solving PDEs, I would strongly recommend starting with a Python library called FEniCS. This is a brilliant finite element solver that allows you to input the bilinear form of your partial differential equation (Google what "bilinear form" is for finite element methods) in Python and generate a solution. This will allow you to practice the mathematics of finite element methods without getting tangled up in the code implementation of the solution process. Solve the Poisson equation first, and then the advection-diffusion.
Simple solvers you might like working with:
EasyCFD -- Educational program intended to teach the basics of a "black-box" CFD solver.
CFD Python -- A Python program designed with a 12-step lesson plan to solving Navier-Stokes equations.
PyFR -- Another Python-based flow solver. Documentation is a bit sparse, so you need an understanding of how CFD works to use it. But once you have that, PyFR's open-source nature allows you to break apart an actual full CFD solver and look at its components before trying to write your own.
Useful literature you might want to check out from your campus library:
White, Fluid Mechanics and/or Cengel and Cimbala, Fluid Mechanics -- Basically the two beginner level fluid mechanics bibles, depending on who you ask. An overwhelming number of engineers out there have had one or the other as their textbook in school. They're both fantastic. Flip a coin.
Moin, Fundamentals of Engineering Numerical Analysis -- Yet another undergraduate bible, this time on numerical methods commonly used by engineers (of all types). It covers material so crucial in all scientific computing that one of my doctoral qualification examiners specifically requested that I know this book from cover to cover.
Anderson, Computational Fluid Dynamics -- Superb introductory book that covers most everything related to CFD. If you're going to buy anything in this list, buy this one.
Hughes, Finite Element Methods -- The bible on finite element methods. The book focuses on structural applications (which do not require stabilization terms) but the mathematics involved are identical regardless of the physics behind the PDE, so this is still a very useful reference.
Zienkiewicz, Taylor and Nithiarasu, Finite Element Method for Fluid Dynamics -- Great supplement to Hughes' book for anyone using FEM on fluid flow. Covers stabilized methods, starting with easy equations (like advection-diffusion) and scaling up all the way to turbulent flows (which you shouldn't bother with right now).
Anderson, Fundamentals of Aerodynamics -- Just putting this down in case you ever need to specifically learn about aerodynamic applications of fluid flow.
Anderson, Introduction to Flight -- Used nationwide as an introductory aerospace engineering book. I recommend it to everybody outside of the industry who wants to work/study in it. Superfluously covers every aspect of the discipline, from structures to propulsion, from aerodynamics to flight control, from aviation to space.
Panton, Incompressible Flow -- Often used as a graduate level book on theoretical fluid mechanics. Focused mathematical approach. Not an easy read, required some prerequisite knowledge of fluid flow (overview of the fundamentals is very brief), but it's the next logical step up when you're ready to take your fluid work further.
If you're looking to get started, you should start with a good book like this one:
http://www.amazon.com/Computational-Fluid-Dynamics-John-Anderson/dp/0070016852
That book starts out with the basics of Fluid Dynamics equations and is really very good.
Turbulence theory and turbulence modeling is a pretty advanced topic. You will first have to learn about laminar boundary layers, boundary layer equations and then about transition to turbulence, turbulent boundary layers and turbulence modeling.
This is the best book I have read on Boundary Layer theory that covers both laminar and turbulent flow:
http://www.amazon.com/gp/aw/d/3540662707/ref=mp_s_a_1_1?qid=1425473580&sr=8-1&keywords=schlicting+boundary+layer&pi=AC_SY200_QL40&dpPl=1&dpID=41ZQZkmQBNL&ref=plSrch
Turbulence modeling is something you can move on to after that. I recommend this book:
http://www.amazon.com/gp/aw/d/1928729088/ref=mp_s_a_1_1?qid=1425473660&sr=8-1&keywords=wilcox+turbulence+modeling
Wilcox goes into much detail about the nature of turbulence and the different methods that have been formulated to model this phenomenon.
Here is a book that talks about the basics of fluid dynamics that is pretty good too:
http://www.amazon.com/gp/aw/d/0123821002/ref=mp_s_a_1_1?qid=1425473759&sr=8-1&keywords=kundu+fluid+mechanics&pi=AC_SY200_QL40&dpPl=1&dpID=41h-Ynv4uGL&ref=plSrch
Another great resource is this set of fluid dynamics videos made a few decades ago. They are awesome and will give you a strong conceptual understanding:
http://web.mit.edu/hml/ncfmf.html
There you go. I'm sorry if I was unclear on anything. Let me know about it and I'll be glad to help you out more.
Now could you point me to some material about how you use hydrodynamics in your field? I love to learn about different fields! Thank you in advance!
/u/another_user_name posted this list a while back. Actual aerospace textbooks are towards the bottom but you'll need a working knowledge of the prereqs first.
Non-core/Pre-reqs:
Mathematics:
Calculus.
1-4) Calculus, Stewart -- This is a very common book and I felt it was ok, but there's mixed opinions about it. Try to get a cheap, used copy.
1-4) Calculus, A New Horizon, Anton -- This is highly valued by many people, but I haven't read it.
1-4) Essential Calculus With Applications, Silverman -- Dover book.
More discussion in this reddit thread.
Linear Algebra
3) Linear Algebra and Its Applications,Lay -- I had this one in school. I think it was decent.
3) Linear Algebra, Shilov -- Dover book.
Differential Equations
4) An Introduction to Ordinary Differential Equations, Coddington -- Dover book, highly reviewed on Amazon.
G) Partial Differential Equations, Evans
G) Partial Differential Equations For Scientists and Engineers, Farlow
More discussion here.
Numerical Analysis
5) Numerical Analysis, Burden and Faires
Chemistry:
Physics:
2-4) Physics, Cutnel -- This was highly recommended, but I've not read it.
Programming:
Introductory Programming
Programming is becoming unavoidable as an engineering skill. I think Python is a strong introductory language that's got a lot of uses in industry.
Core Curriculum:
Introduction:
Aerodynamics:
Thermodynamics, Heat transfer and Propulsion:
Flight Mechanics, Stability and Control
5+) Flight Stability and Automatic Control, Nelson
5+)[Performance, Stability, Dynamics, and Control of Airplanes, Second Edition](http://www.amazon.com/Performance-Stability-Dynamics-Airplanes-Education/dp/1563475839/ref=sr_1_1?ie=UTF8&qid=1315534435&sr=8-1, Pamadi) -- I gather this is better than Nelson
Engineering Mechanics and Structures:
3-4) Engineering Mechanics: Statics and Dynamics, Hibbeler
6-8) Analysis and Design of Flight Vehicle Structures, Bruhn -- A good reference, never really used it as a text.
G) Introduction to the Mechanics of a Continuous Medium, Malvern
G) Fracture Mechanics, Anderson
G) Mechanics of Composite Materials, Jones
Electrical Engineering
Design and Optimization
Space Systems
John D. Anderson writes amazing books, and his computational fluids dynamics book is a work of art.
http://www.amazon.com/gp/aw/d/0070016852?pc_redir=1406696573&robot_redir=1
I'm a personal fan of Anderson's CFD. A professor recommended CFD for Engineers, but I haven't looked at that resource yet.
http://www.amazon.com/Computational-Dynamics-McGraw-Hill-Mechanical-Engineering/dp/0070016852
Check out chapter 10 of the Anderson CFD book. It's an explicit FD formulation of this exact problem.
Link: https://www.amazon.com/dp/0070016852/ref=cm_sw_r_cp_apa_xiTZAbSJCCYF4
If you're just looking for source code, it's somewhere out there on them interwebs, in Matlab and C at least.
If you don't mind the 'aerospace perspective', this is a very good book. You can also check /r/CFD.
I figured responding would be better than downvoting and what not. Here's a short list of some good textbooks to start with.
Fluid Mechanics: Fundamentals and Applications: This is my favourite general fluid dynamics textbook.
Race Car Aerodynamics: Designing for Speed: Considered one of if not the best textbooks for race car specific aerodynamics.
Race Car Vehicle Dynamics: This is the defacto vehicle dynamics textbook. I don't think any F1 engineer out there hasn't read this.
Computational Fluid Dynamics: The CFD Bible.
PM me if you want ahem links to the digital versions. Sorry if I've been harsh earlier, everyone starts somewhere and some concepts aren't particularly intuitive. You've got the right attitude though, a better feel for aerodynamics will come soon enough.
https://www.amazon.ca/Computational-Fluid-Dynamics-John-Anderson/dp/0070016852
I'd recommend starting with this. Yes, it's from 1995 but the basics haven't changed. He walks you through the math for a not-so-simple solver and there's some sample code. Possibly Fortran but I can't recall.
Either way, it's a good way to get your feet wet. You can learn about the more advanced techniques later.
I had to do a lot of de-bugging. I had some dumb errors like calculating variables before the variables that they were dependent on. I also had to re-apply the BC after the predictor. After your first comment I went back and placed the dlnA1(j) in its own loop because I was not applying it to the boundaries only the interior of the matrices.
I also got this text
It has my exact problem as an example on the last ~50 pages with table values for the first time step which helped verify my code.