THE FUTURE OF CFD
 

(1). As the foot steps of the century is coming to the end, for some people, the future of CFD becomes an important question. (2). As we have just celebrated the 30th anniversary of man on the moon, can we learn something from the history? And ask, What is the future of Appolo moon landing program? (3). Looking back, there were 10 million dollars super-computers for CFD back in late 70's. What are the future of those super-computers? (4). As the new fighter gradually sinking into the sea of over-cost, would you like to propose CFD for cost-reduction? Or should the CFD work should be cut to save the cost? (5). The fact is, similar to the space program, the main stream CFD disappeared at the end of 80's. The left-over somehow was transformed into various shapes of commercial codes. Under the skin of the life-less code, there are signs of struggle for life, for survival, for recognition, for identification. (6). You can hear it, you can feel it, and you can smell it. Like a small weed in the hot desert sun, dried and waiting for a summer afternoon rain storm. (7). To be realistic, wise persons still around. But they know how to hide their knowledge for the bad time to come. It is useless to spend every night to pack it into a CFD code. (8). If a 10 dollars recipe book can turn a man into a French chef, French restaurants would be long gone many centuries ago. (9). As the century is coming to an end, is it really that difficult to find a French restaurant with a good French chef? The same is true with the future of CFD. (10). As the door is closing, it will seal that precious knowledge into the bottom of human brain. (11). As the summer afternoon rain storm come at the begining of the next century, something like desert yellow flowers will again cover the desert land. Will the code still be there?

Re: THE FUTURE OF CFD
 

About the future of CFD, I have a vision:

Now a CFD package does normally only in the following route:

geometry + boundary conditions ---> solution of flow field

I hope a CFD package in the future reverses this route as follows:

boundary conditions + hoped flow field + expert system ---> optimized geometry

I know it is very difficult but it is an efficient way.

X. Ye

Re: THE FUTURE OF CFD
 

John, some of your postings take on an interesting poetic form, and your metaphores remind me of zen bhuddism descriptions of nature and life in general. But please, can we bring this forum back to mostly TECHNICAL discussions in the field of CFD ? Thank you !

Re: THE FUTURE OF CFD
 

I think it's obvious that CFD, and the whole field of computational physics, is here to stay and will grow. The death that you speak of at the end of the 80's was the end of the cold war. Naturally the defense driver doesn't exist the way it used to. But commercial applications are growing. And with the rise of the next superpower, the defense driver will come back. I'd be a little more optimistic about the future of CFD.

Re: THE FUTURE OF CFD
 

agree and we started to try, very preliminary though.

Re: THE FUTURE OF CFD
 

I would like to know why your e-mail address has suddenly changed. I have the sneaking suspicion that you are not who say you are or perhaps you have gone off the deep end. If the former is true please state your true name, and not putrify someone else's name.

Re: THE FUTURE OF CFD
 

(1). Thank you for your interest. (2). On Internet, cfd-online is not cfd-online. It is a bunch of numbers only. (3). On Internet, the e-mail is free, the software is free, and the computers are also free. (4). So, I guess you are new to cfd-online. Why not try the search option on this forum and do a name search on John C. Chien or Chien. It is a good idea to dig into the archive section. (5). Nothing is real on the Internet. That is why they are called virtual environment.

Re: THE FUTURE OF CFD
 

(1). Good idea. (2). But, I think it has been used in industries for many years already, for example, the inverse design of turbine blades. (3). There are codes available and they also have been used in actual design processes for many years. (commercial codes? no.)

Re: THE FUTURE OF CFD
 

(1). Good idea. (2). But, I think it has been used in industries for many years already, for example, the inverse design of turbine blades. (3). There are codes available and they also have been used in actual design processes for many years. (commercial codes? no.)

Re: THE FUTURE OF CFD
 

(1). Thank you very much for your suggestions. But there are valid reasons for that opening speech. (2). The space was brought about not because someone like Godard was interested in rocketry. It was a simple decision of a president. A leader who took the technology into a new era. (3). Likewise, the aeronautical wind tunnel facilities were also created largely by some general in the Army. (4). Without the leadership, it is very hard to make any progress in technology. (5). So, the point I was trying to make was: the future of CFD needs a powerful leader. A good example? Former CEO of Chrysler, or the current CEO of Microsoft. Or like Navier, Stokes who invented Navier-Stokes equations more than 100 years ago. (6). Technology comes from the applications of physics, which is expressed in mathematics, which is derived from logics, and which is created from the mind of innovation. Let your mind float above all of these small detailes of everyday life. (7). I have not heard any voice from learders of commercial industries that CFD will play an important role in their future business decisions. Without that kind of support and vision, one can always work in one's backyard on his commodore64? or Amiga1000? AppleII... ( I heard that the former Chrysler CEO is selling electric bicycles. But, then we have to find the CFD problem for the electric bike first. I am quite sure that he is not selling CFD.)

Re: THE FUTURE OF CFD
 

(1). Sorry to ask you this question. (2). In my thiry years of research work in CFD, I have never come across this new theory called " Zen bhuddism ". But I have seen books on "Zen" in business section of bookstores. I have never studied this kind of theory. Is it popular in France? I did visit some beautiful temples when visiting Taiwan. Do you think that there is some connecting between the "Zen bhuddism" and "CFD"? Is this the opposite side of "chaos" or "fractal"? (3). I am just curious about it. And you are the first person mention this theory here. If it is not technical, you don't have to answer it.

Re: THE FUTURE OF CFD
 

They are those stubborn obstacles for the technology 'evolution' in industries, non-sense to keep only for themselves. They could make big fortune by selling them out. They still have the chance. Big 3 are dumping their own secret codes and turning to commercial ones. Most suppliers will be forced to follow. Commercial codes will have more money to hire more smart people to develope more sophisticated codes to the market at cheaper price. They also provide group brains for professional tech support. Secret keepers will soon fade out.

Re: THE FUTURE OF CFD
 

I think that CFD has an excellent future. As computing power becomes cheaper and algorithms become more efficient more industries can afford to take advantage of CFD and improve their designs. I seems that in the past two years that the number of commercial CFD codes has more than doubled (this is my perception, I haven't counted, it could just be better marketing). After some reflection, it may be that Mr. Chien is lamenting the end of the pioneering era of CFD and not the end of CFD altogether (though he may not realize it). From reading Mr. Chien's post's, it seems that he has been involved in CFD for many years, was involved in the defence industry and strongly advocates the ability of an analyst to be able to write his/her own code. He may have been involved at a time when there were no commercial codes expensive computers were required (which only the government, universities and very large corporations could afford) and it was the domain of a small elite group. Now anyone with a bachelor's degree in engineering who can point and click can call themselves a CFD analyst. This is similar to the original group of Internet users who feel it has been ruined by the unwashed masses who now litter the Usenet group and spam others en mass. Just my two (uhh, make that five) cents.

Re: THE FUTURE OF CFD
 

This is one of the oldest problems in CFD. I think the final purpose of CFD is to design fluid dynamic systems and any of their component but not only to verify how the flow is or compute what the flow is. It falls in the category of optimization design and flow control. It has been used in industries for many year, for example Boing and MD. Although CFD companies just started to creat their CFD design software recently, I believe that it will extensively used in the industries in the near future. As I know, for commercial softwares, NUMECA Co. Ltd has developped a 2D version and they are planning to extend their work to 3D. Some other companies (FLUENT ?, STAR-CD ?) also begin to do this. By the optimization techniques, the shape is modeified to improve the performance of fluid systems to approach targets including prescribed pressure or velocity distributions, lift range, maximum lift, minimal drag, shock-free suction side in transonic flow and type of stall at subsonic speeds under geometrical constraints. Differently from the method of traditional linear design, the optimization design combines optimization thoery and CFD so that the nonlinear effect is introduced in the design process. The optimization methods currently used are gradient-based method, genetic algorithm, neural networks thoery, and so on. We can get a optimum shape by computer just in a few days. However the biggest problem is still the accuracy of CFD results. You may read J. of Aircraft, 1999.1. I am working in this field and currently doing supersonic aircraft design only for acadmic research. But if I got a good chance, I would like to work in a company to creat such a software.

Z. Lei

Re: THE FUTURE OF CFD
 

(1). You are always right. It is always important to leave room for readers imagination and draw his own conclusion. (2). Read the next posting of "Salary Analysis and CFD jobs". The future is always in your own hands, not in my words.

Re: THE FUTURE OF CFD
 

try adapco or fluent. their core developing centers are in England though.

Re: THE FUTURE OF CFD
 

interesting concept. but why limit to 'hoped flowfield' (inverse design) in which case you get what you want which is not always the best and to 'expert system' which is only one technique of automatic design, why not say "automatic design system" which can incorporate many tecniques.

i agree with you though that analyses is not the prupose of design results are. as well as good analysis tools we need automatic design tools to produce better products faster. it is all well and good to have great CFD code (the structural people already have this in FEM) but what to do when system is complicated and redesign is tricky and time consuming. fluid flows are very sensitive and even a good engineer often has difficulty coming up with better design. this optimisation/automatic design field is growing but there's more to come

Re: THE FUTURE OF CFD
 

more than just inverse design John - we need optimization

Re: THE FUTURE OF CFD
 

i rather liked this posting. i think after you read john long enough you get to understand his postings. the first time i read his stuff i was bamboozled. now it's not so bad. i think in additon to the technical stuff we also need discussion on the philosophy of cfd. i remember talking to a gentleman at Pratt and whitney who said it's notupwind or central diffrence or lax wendroff or runge kutta its getting the job done as good as possible (i paraphrase). we do need the nitty gritty but sometimes we also need the zen to truly understand. otherwise we'll might end up as one of those people using 4 stage runge kutta with artificial dissipation to solve flow of water in pipes

Re: THE FUTURE OF CFD
 

more than anything else we need people who understand what the three letters in CFD mean together with each other. you can know C but without FD you don't know CFD and vice versa. sorry to say also that many have neither C or FD

Re: THE FUTURE OF CFD
 

(1). I think, that is one area where the human brain, the thinking logic, the computer system, and the computer language must work together. I said "must". (2). The computerized automatic optimization can be done. But the reality is more jobs will be eliminated. (3). Currently, the design systems are configured to fit the human activities. The simplest example is the use of CAD. Stored data base in parametric form can easily eliminate the CAD engineer, not mentioning the smart CAM programs to create optimized machine tool path automatically to create the parts. (4). It is always important to think whether the future will be "machine-centered" or "human-centered".

Re: THE FUTURE OF CFD
 

(1). The future of CFD depends on whether it can serve the human being or not. (2). To serve human being effectively, CFD must take in a proper form. (3). One of the form is a CFD code. (4). Take for example of an automatic IC plant, where an IC chip is automatically produced through several hundred of different steps. When the final chip has one defect in it, it is garbage. You can not say that one error out of one million semi-conductors on the chip is only 0.000001 . (5). So, sometime in the future, when this automatic fully-optimized cfd system produces a product(say a blade geometry) which is obviously wrong, are you going to use another system to correct it? Or at that point, you still have some talented engineers around to find the source of errors and fix it? Or just like the bad ICs, they simply ended up in the garbage cans. (6). You can build many redundant systems into this automatic optimization system. But in the end, like space shuttle systems, launch vehicle systems,... it still depends highly on human being's brain. (7). Can you write a code to automatically check out a CFD code and fix the bugs? So far, most commercial codes or in-house codes can only stop the execution when the solution diverges.

Re: THE FUTURE OF CFD
 

Human brain is the biggest supercomputer. The computerized automatic optimization is designed by human. It seems like in future only the creative people in their field of specialization will be in top. I agree with you that in reality more jobs will be eliminated with modern computerization. Those who are average or below average in their field will do only the same kind of work on a daily basis. Those scientists or engineers who have facilities to use supercomputers to solve CFD problems in reality will be in much better positions than the CFD analysts who only have access to commercial softwares. In future,(since commercial softwares have limited applications and memory allocation) commercial CFD softwares will be used by average and below average CFD analysts to solve the same kind of problem on a daily basis.

Re: THE FUTURE OF CFD
 

(1). In some companies, it is already in this way. (2). Similar to Henry Ford's concept, there will be CFD assembly lines. And there also will be researchers and scientists working on the more fundamental issues like numerical algorithms, turbulence modelling, anmation and visualization, integrated design information systems. (3). Recently, someone has already modified a PC CPU to run at 800MZ or 1000MZ. So, everyone will have access to the super-computer class PC workstations. (4). It is therefore very important for the engineering managers or company CEO to have a clear picture of this dynamic development of both the hardware and the CFD. Failure to do so will create great chaos in the company's engineering department and unable to produce competitive products in time to meet the market need. (5). This complex technological environment will pose a big challenge to the future comapny planners. I would say, from the use of the computer systems alone, today's system of networked distributed computing environment is much less efficient and reliable than the old centralized main frame computers. The routine network down problem is fairly common to many morden companies. What I am trying to say is: many companies are running CFD problems on workstations (or networked computers), while these problems should be run from the begining on the super-computers. The mis-match between the computer and the cfd problem has a bad consequence of un-reliable and un-useable results due to inadequate mesh points and poor models.

Re: THE FUTURE OF CFD
 

Are you kidding me John! I mean Cray, Teraflop etc. etc. .... !

Re: THE FUTURE OF CFD
 

(1). I mean old Cray.

Re: THE FUTURE OF CFD
 

"NAS" Cray system

Re: THE FUTURE OF CFD-1000MHz PC CPU
 

(1). The information forwarded to me about the 1000MHz and 800MHz PC CPU from my son ( who has a popular website on libretto. http://www.cerfnet.com/~adorable/overclocking.html ) is : (2). http://www.hardwarecentral.com/hardw...torials/718/1/ (3). http://www6.tomshareware.com/cpu/99q3/990823/index.html (4). The old Cray I used has one Meg words fast RAM only. We could only ran a small 3-D Navier-Stokes problem. A mini-computer then was using virtual memory and can handle large 3-D problems. (5). If you are using the current super-computer, you are working in the paradise.

Re: THE FUTURE OF CFD
 

John, you are trying to undermine the supercomputer used by Nick Georgiadis along with his group at NASA.

Re: THE FUTURE OF CFD
 

(1). The old Cray computer I used was belong to a private company. In early 80's, because of the need to do CFD work, we were able to get the company to buy a Cray computer. (2). There are many many companies in the world using super-computers. I think, you are right that NASA also uses super-computers. I don't know what computers they use. I have no connection with any NASA before. (3). I am talking about my personal experience using the super-computer and PCs. The only software I have used which were developed by a contractor at a NASA lab is Plot3D (and FAST). I don't see your logic about the connection between my experience and the NASA. (4). You are still free to create your own story.

Re: THE FUTURE OF CFD
 

i posted to this thread a few days ago saying that the future of CFD was in all sorts of automatic design techniques (optimisation , inverse design , neural networks etc) but i've come to the realisation after reading through the thread "extremely simple problem... can you solve it properly" posted by some guy named Mikhail that the future of cfd indeed all of engineering is proper education and a real knowledge of physics. this man was going on and on about some mathematically well posed but physically impossible problem that is best solved by hand. it troubled me that this person might be the man designing my gas stove or something. i think the best thing we can do is to pass on our knowledge

Re: THE FUTURE OF CFD
 

Don't worry about such posted message as "extremely simple problem... can you solve it properly". The thinking process of such message is reversed. We have firstly the problem of physicas then we model it mathematically. The reversion has no sense. It is somewhat like the confusing drawings of Escher: The structures he drew can not exist in the reality but can exist optically on paper.

About the "expert system", I mean a design software system containing experience and wisdom of million researchers and engineers working on fluid dynamics. There has been a software named as "Invention machine" containing the experience of the engineers of the aerospace and millitary industry of the ex Soviet Union.

X. Ye

Re: THE FUTURE OF CFD
 

oh yeah i know about expert systems. but the point i was trying to make before was that most of the time one optimisation is notdemonstrably better than the other ie each has advantages in certain areas and disadvantages in another. so a combination of these is better than one. if you'd like could we start a new thread to discuss this. i don't like hanging on a thread if i'm discussing the original problem