What is the future of CFD and why?

CFD is mainly used in the engineering industry (finite volume, finite element are the mainstream, these methods are local, generally speaking, low-order, the advantage is that it can deal with complex shapes, boundary conditions), in addition to many high-order methods: global elemental spectral method, mainly used in theory. I don't know if Zhihu focuses on high-order methods, and from the image results, the main differences between low-order methods and high-order methods are:

With the same mesh accuracy, higher-order methods can characterize fine structures. CFD development is not well understood, but the theoretical basis of low-order numerical methods is well established, and it is mainly limited to computers: using more and better CPUs, such as MPI, or GPU algorithms.

The theory of higher-order methods relies more on Doodler's understanding of physical processes, because it is the sum of any complex function into a series of simple functions, or slightly more complex functions (such as wavelets), and a good basis fun must come from an educated guessBut there is one thing in common, CFD is like poison, the result picture is very shocking (although it may be wrong), it is easy to make people feel satisfied as an artist, but if you don't know much about physics itself, there is no difference between being a CFD and an animation director, I think the domestic academic prospects are still good in the future, CFD is considered the strength of Chinese people in applied mathematics, but I feel that there are few people who do physics experiments, which may be due to the focus of the long-term education system. If you don't understand the employment method, you can't find a job anyway!

It will be much better abroad, although many of the oil companies are finite elemental simulation of ...In fact, a line of code has not been written. <>

<> to understand the advantages of CFD, it is necessary to compare it with purely theoretical fluid mechanics and experimental fluid mechanics.

CFD is virtual, saving hardware development time, and full-scale simulations of some large-scale models (aircraft, culverts, etc.) are relatively inexpensive. Purely theoretical fluid mechanics cannot solve equations based on limited understanding, and few can be applied to industrial solutions, and experiments are often expensive and time-consuming, it is difficult to independently consider the influence of a certain factor, and it is generally impossible to carry out full-scale experiments and fully simulate the actual environment. The above shortcomings can be overcome by CFD.

However, due to the shortcomings of the algorithm, there are still limitations to CFD processing for some problems, and the high-precision simulation of turbulence has always been an insurmountable problem, and the hardware limitation of high-precision DNS is not very realistic, and in some cases, the verification of grid independence lacks basis, and it is necessary to rely on experimental results to prove it.

Hope it helps.

Back to the topic, let me talk about the celebratory role of CFD in the field of construction engineering consulting. As mentioned by the masters, those who are proficient in CFD must have at least three attainments, physics, advanced mathematics, and computers, all of which are indispensable. Therefore, CFD can be said to be a research direction that can allow you to learn knowledge and satisfy your curiosity.

At work, you don't need to be proficient in CFD technology, under the leadership of the technical director, you can also make a colorful flow of lead body diagrams. We will use CFD for indoor and outdoor natural ventilation, analyze wind farms, give assessment reports, and earn consulting fees. A project costs from tens to hundreds of thousands.

The prospect can be said to be good, and live decently. In addition, some people mentioned that the application of CFD in movie special effects and game special effects is very attractive, and the treatment should be much better, which is worth paying attention to. PS I am ready to continue my studies in the CFD field and enter the algorithm camp, and I am very excited to see so many KOKUYO guessers who are engaged in CFD gathered here to discuss and communicate.

It is a branch of mechanics that mainly studies the static state and motion state of the fluid itself under the action of various forces, as well as the mutual brightness and flow law between the boundary wall of the fluid and the solid.

Fluid mechanics is a branch of continuum mechanics, which is the science of studying the phenomena of fluids (including gases, liquids, and plasma states) and the related mechanical behavior. It can be divided into hydrostatics and hydrodynamics according to the movement mode of the research object, and the socks can also be divided into hydraulics, aerodynamics and so on according to the type of flowing substance. The basic equation that describes the characteristics of fluid motion is the Navier-Stokes equation, or N-S equation for short.

The Navier-Stokes equation is based on Newton's second law and represents the interrelationship between fluid motion and the forces acting on the fluid. The Navier-Stokes equation is a nonlinear differential equation that contains variables such as the velocity of motion, pressure, density, viscosity, temperature, etc., which are all functions of spatial position and time. In general, for general fluid kinematics problems, the Navier-Stokes equations need to be solved simultaneously with the conservation of mass, energy, thermodynamics, and the material properties of the medium.

Due to its complexity, it is usually only possible to solve the problem by means of computer numerical calculations under given boundary conditions.

The most studied fluids in fluid mechanics are water and air. When Bernoulli published his monograph in 1738, he first adopted the term hydrodynamics as the title of his book; Around 1880, the term aerodynamics appeared; After 1935, people generalized the knowledge of these two aspects and established a unified system, collectively known as fluid mechanics. <>

Fluid mechanics has been gradually developed in the struggle between human beings and the natural world and in the practice of production. The ancient Egyptians governed the flooding of the Nile in ancient times, and in ancient China, there was a legend that Dayu controlled the water and dredged the rivers; The Dujiangyan River built by Li Bing and his son in the Qin Dynasty led by the working people is still playing a role today; Around the same time, the ancient Romans built a massive system of water supply pipes and so on.

The first contributor to the formation of the discipline of fluid mechanics was Archimedes of ancient Greece, who established the theory of liquid equilibrium, including the law of physical buoyancy and the stability of the floating body, and laid the foundation of hydrostatics. Since then, there have been no major developments in fluid mechanics for more than a thousand years. <>

In the 19th century, engineers were trying to solve many engineering problems, especially those with sticky effects. So they used fluid mechanics partly and partly semi-empirical formulas that summarized the results of the experiments, and they formed hydraulics, which is still developing in parallel with fluid mechanics today. In 1822, Navier established the basic equation of motion for viscous fluids; In 1845, Stokes derived this equation on a more rational basis and convincingly demonstrated the basic concepts of macroscopic mechanics involved.

This set of equations is the Navier-Stokes equation (n-s equation for short), which is the theoretical basis of fluid dynamics. The Euler equation mentioned above is a special case of the n-s equation when the viscosity is zero. <>

Fluid mechanics was developed a long time ago as a part of physics.

In the 19th century, fluid mechanics developed along two aspects: on the one hand, a large number of famous mechanical mathematicians engaged in theoretical research on fluids as non-viscous, which played a very important role in the development of mathematical physics methods and complex variable functions; On the other hand, due to the needs of irrigation, water supply and drainage, shipbuilding, and pipeline fluid transportation in various industries, engineering fluid mechanics, especially hydraulics, has been highly developed.

The key to unifying the two is the introduction of the boundary layer theory at the beginning of this century, the central idea of which is that in most areas, fluids can indeed be regarded as non-viscous because they play a small role.

Interestingly, this boundary layer phenomenon found in fluid mechanics was quickly echoed in other scientific fields, because it contained a broader and deeper content. This greatly promoted the development of applied mathematics, thus forming the "" that is now widely used in many sciencesAsymptotic matching method".

The phenomenon first discovered in fluid mechanics and the theories proposed for it are not the only ones that have been discovered to exist and be useful in other disciplines over time.

For example, the solitary waves observed in water waves 100 years ago and their theories were found to exist and be useful in sound waves and light waves in the 60s of this century, and a systematic theory was quickly formed. At present, optical communication, which has important application prospects, is based on the soliton (solitary wave) theory.

The above examples are enough to illustrate the role played by the study of fluid mechanics in the development of modern science, and this phenomenon has its profound backgroundFirst of all, fluid motion is a macroscopic phenomenon that is most convenient for humans to observe and perceive.

Fluid mechanics is the foundation of many industries. The most prominent example is the aerospace industry. It is no exaggeration to say that without the development of fluid mechanics, there would be no aerospace technology today.

Of course, the needs of the aerospace industry are also the most important driving force for the development of fluid mechanics, especially aerodynamics.

Fluid mechanics is gradually developed in the struggle between human beings and the natural world and in the practice of production. The ancient Egyptians governed the flooding of the Nile in ancient times, and in ancient China, there was a legend that Dayu controlled the water and dredged the rivers; The Dujiangyan River built by Li Bing and his son in the Qin Dynasty led by the working people is still playing a role today; Around the same time, the ancient Romans built a massive system of water supply pipes and so on.

The first contributor to the formation of the discipline of fluid mechanics was Archimedes of ancient Greece, who established the theory of the balance of liquids including the law of physical buoyancy and the stability of floating bodies, and Yinjia laid the foundation of hydrostatics. For more than 1,000 years, there was no major development in fluid mechanics.