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PhD Student in Aero Eng July 21, 1999 14:12

What is CFD

I was hoping that someone could explain what CFD is to me please. Thanks in advance.

Patrick Godon July 21, 1999 14:44

Re: What is CFD
How can one be a PhD student in Aeronautics and not know what is CFD?

Computational Fluid Dynamics (CFD) will help you to find what is the lift and drag on the wings of your plane (airfoil NACA 0012, why not?) by modeling the flow of air around the wings using numerical models (computer simulations) that solve the equations of the flow.

clifford bradford July 21, 1999 16:17

Re: What is CFD
I too am curious how a man can be phd student and not have an inkling waht cfd is. cfd is any technique by which the performance of a fluid sytem can be estimated/predicted by use of computer programs. since you're an aero engineer you'd (and most of the readers of this group) would be interested in simlating flow over aircraft or inside aircraft engines (myself). however cfd in various forms is also useful for piping design, heat exchanger design, design of hydro-pneumatic systems etc. learn about it man. it's the future

John C. Chien July 21, 1999 17:34

Re: What is CFD
(1). First of all, there is no unique definition of "CFD". (2). You can say that everyone has is own definition of "CFD". My car is a car, and your car is a car. But "my CFD" is definitely not the same as "someone's CFD". How could this happen? (3). This is because "CFD" is still in it's early stage of development. For example, if you graduate from a medical school, you are a medical doctor, a working medical doctor. (4). If you get a PhD on a new and more efficient method to solve Navier-Stokes equations, can you design an aircraft? or an engine? Unlikely! (5). Or if your PhD dessertation is on mesh generation or near-wall turbulence model, are you still an aerospace engineer? (6). Maybe, you were lucky and were able to use a commercial code in your dessertation. But the company trying to hire you does not have that code, what are you going to do? What is the company going to do? (7). These are sample reasons why "CFD" is not uniquely defined. (8). But, I can tell you what people in industries are doing with "CFD". In aircraft and engine industries, CFD codes to solve flow equations at various degrees of complexity are being used to obtain design information to support new product (new aircrafts, new engines) design, and existing product services. While twenty or thirty years ago, these activities were carried out using slide rules, analytical solutions, empirical formula and wind tunnel testing. (9). In general, the elements involved in "CFD" is parallel to the processes involved in wind tunnel testing, except that most activities are carried out on computer. ( computer geometric modeling, computer mesh generation, computer solution of Navier-Stokes equations, Euler equation, computer graphic animation of computed solutions)

Nuray Kayakol July 22, 1999 03:20

Re: What is CFD
Or (6). Maybe, you were unlucky and were able to write a commercial code in your dessertation. But the company trying to hire you have that code, what are you going to do? This is also another problem for anyone.

Axel Rohde July 26, 1999 08:40

Re: What is CFD
I have a free educational CFD program for download at which you should try. I think this will give you an idea about CFD!
