What kind of pit does CFX use
Publish: 2021-04-01 06:23:44
1. Reference answer: Bamboo peach blossom three two branches, spring river water warm ck prophet
2. It seems that I don't understand the essence of these things< CFD is computational fluid dynamics, it can be said that it is a big research direction or research method
FEM is an algorithm in CFD Research
CFX and fluent belong to ANSYS company, they are computational fluid software, namely CFD software, fluent has a wide range of applications, CFX focuses on some professional fields, each has its own advantages<
ANSYS belongs to a large platform, including various computing software
to sum up, the above things have subordination, inclusion and juxtaposition, so the questioner seems to be asking: where can the air force, Navy, Colonel, machine gun and army attack Japan.
FEM is an algorithm in CFD Research
CFX and fluent belong to ANSYS company, they are computational fluid software, namely CFD software, fluent has a wide range of applications, CFX focuses on some professional fields, each has its own advantages<
ANSYS belongs to a large platform, including various computing software
to sum up, the above things have subordination, inclusion and juxtaposition, so the questioner seems to be asking: where can the air force, Navy, Colonel, machine gun and army attack Japan.
3. As for the flat bottomed forebay of pumping station, why the mainstream of CFX calculation is higher? I don't understand what you mean, so I can't help you. I hope you understand.
4. Comparison between fluent and ANSYS CFX
1. Fluent was acquired by ANSYS in 2006
in the United States, finite volume method, FVM method and fluent have developed the following procts: widely used! Support C & # 92; C + + language development
fluent 6.2-a general CFD solver based on unstructured grid, the former is structured grid solver, such as version 4.5 and 5.5
the software design of FLUENT is based on the idea of CFD software group, from the perspective of user needs, aiming at various physical phenomena of complex flow, fluent software adopts different discrete formats and numerical methods, in order to achieve the best combination of calculation speed, stability and accuracy in specific fields, so as to efficiently solve the problems of complex flow calculation in various fields. Based on the above ideas, fluent has developed flow simulation software suitable for various fields. These software can simulate fluid flow, heat and mass transfer, chemical reaction and other complex physical phenomena. Unified grid generation technology and common graphical interface are used between the software. The difference between the software is only e to the different instrial background, So it is very convenient for users< GBR / > gambit is a special CFD preprocessor (geometry / grid generation). Fluent series procts use gambit preprocessor software developed by fluent company to build geometry and generate grid. It is a preprocessor with super ability to build model, and then solved by fluent< CFX was acquired by ANSYS in 2003
British finite volume method FVM method and finite volume method based on finite element. Support C & # 92; C + + language development
grid capability (fluent gambit is inferior to ICEM CFD)
accuracy (fluent is not as good as CFX, the default difference scheme of CFX is second-order, but it is difficult for fluent to converge with the second-order scheme)
reliability (fluent is not as good as CFX). By heart, CFX's coupled solver converges much faster than fluent's. That's an order of magnitude difference.)
parallel capability (fluent is not as good as CFX. These two softwares have been used to solve problems such as aircraft outflow on multi CPU clusters. Fluent is too slow.)
post processing (fluent's post-processing diagram is too rustic, compared with CFX's, it's much more beautiful and professional.)< The advantages of CFX are abundant physical models and powerful functions. The finite volume discretization method based on finite element method has high accuracy but slow calculation speed; There is a lack of fluent physical model, and there is no corresponding model for many problems. For example, each phase of multiphase flow cannot be multi-component, and multiphase flow composed of wet air and other fluids cannot be considered. Moreover, the pre processor format of FLUENT is closed, which can only be suitable for fluent, and the pre processor ICEM of CFX has rich output formats< I've used CFX for a long time, and occasionally used fluent. I know that CFX has some shortcomings, and I also know that fluent is strong in some aspects.
1. There is only one kind of full implicit solver in CFX, and there are three kinds of fluent: progressive, full explicit and full implicit.
although CFX has less iteration, it consumes a lot of memory.
2, There are many unknown functions in the UDF (user Fortran in CFX) of CFX, so it is not easy to develop complex models. The UDF (in C language) of fluent can provide relatively complete information query< The GUI of CFX is really better than that of fluent, with good pre-processing and post-processing, and good coordination. Fluent just doesn't focus on the improvement of GUI, but it can achieve the same function. Just be used to it. The focus of CFD code is to avoid mistakes and misunderstandings. Does code developer rece CFD code error as much as possible!, GUI friendliness is not the key point. Basically, the accuracy of solution has a lot to do with the user's skill. For the same software and the same problem, some people solve it wrong and some are OK.
5. There are many users of the two kinds of software, and it is not easy to integrate them into one, but they may complement each other and improve at the same time.
6, The latest academic or instry research results will probably be reflected in the solver models, which is similar.
- --- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -. The efficiency of Yang Cheng calculated by these two softwares is almost the same, and the difference is 5%. This is already very big. Why? The torque calculated by FLUENT is 880, while the torque calculated by CFX is 850. It is because the torque difference is so much that the efficiency will be so poor. Why are the two CFD softwares so different when calculating the same pump? I heard some people say that CFX is more suitable for rotating machinery. Is that so? Is CFX more accurate than fluent? I hope you can give me an answer
whiz 2013-09-06 17:49
the difference of 5% between the two software results is not big<
z41906957 2013-09-13 22:56
how big is it
qianzd 2013-09-26 11:55
check your torque calculation surface, there should not be such a big gap
Rexxar 2013-09-27 03:07
5% is acceptable, if there are experimental data, compare with the actual test, In my previous experience of calculating pumps and turbines, the efficiency of FLUENT is always slightly lower than that of the experiment, while CFX is higher than that of fluent
in fact, the result of FLUENT is more conservative, and the characteristic curves calculated by the two softwares are similar
but the engineers feel that the efficiency of numerical calculation should be higher than that of the experiment It makes people think that CFX works well
and a series of software has been developed for CFX of rotating machinery for a long time, which is very convenient from pre-processing to post-processing, which also makes people in this field tend to use it
now that both of them are mastered by ANSYS, the difference should be smaller
Tianma sk 2013-09-28 11:32
listen to what you say, that is, the CF for water pump If x is calculated, the result is the closest to the experimental result? In other words, it is better to use CFX for water pump
turbulence 2013-09-30 21:04
What about grid independence? Is the model strictly consistent? Is the numerical format consistent<
Rexxar 2013-10-08 16:30
take a look at the suggestions on the sixth floor
the accuracy of the calculation results needs to be compared, and the experimental results or the recognized calculation results
I think CFX is more convenient to operate, and the calculation is good near the design condition, but some off design conditions are not very good, It depends on which one you choose.
in addition, it's not reliable to only rely on numerical calculation to obtain accurate performance parameters, whether it's fluent or CFX
1. Fluent was acquired by ANSYS in 2006
in the United States, finite volume method, FVM method and fluent have developed the following procts: widely used! Support C & # 92; C + + language development
fluent 6.2-a general CFD solver based on unstructured grid, the former is structured grid solver, such as version 4.5 and 5.5
the software design of FLUENT is based on the idea of CFD software group, from the perspective of user needs, aiming at various physical phenomena of complex flow, fluent software adopts different discrete formats and numerical methods, in order to achieve the best combination of calculation speed, stability and accuracy in specific fields, so as to efficiently solve the problems of complex flow calculation in various fields. Based on the above ideas, fluent has developed flow simulation software suitable for various fields. These software can simulate fluid flow, heat and mass transfer, chemical reaction and other complex physical phenomena. Unified grid generation technology and common graphical interface are used between the software. The difference between the software is only e to the different instrial background, So it is very convenient for users< GBR / > gambit is a special CFD preprocessor (geometry / grid generation). Fluent series procts use gambit preprocessor software developed by fluent company to build geometry and generate grid. It is a preprocessor with super ability to build model, and then solved by fluent< CFX was acquired by ANSYS in 2003
British finite volume method FVM method and finite volume method based on finite element. Support C & # 92; C + + language development
grid capability (fluent gambit is inferior to ICEM CFD)
accuracy (fluent is not as good as CFX, the default difference scheme of CFX is second-order, but it is difficult for fluent to converge with the second-order scheme)
reliability (fluent is not as good as CFX). By heart, CFX's coupled solver converges much faster than fluent's. That's an order of magnitude difference.)
parallel capability (fluent is not as good as CFX. These two softwares have been used to solve problems such as aircraft outflow on multi CPU clusters. Fluent is too slow.)
post processing (fluent's post-processing diagram is too rustic, compared with CFX's, it's much more beautiful and professional.)< The advantages of CFX are abundant physical models and powerful functions. The finite volume discretization method based on finite element method has high accuracy but slow calculation speed; There is a lack of fluent physical model, and there is no corresponding model for many problems. For example, each phase of multiphase flow cannot be multi-component, and multiphase flow composed of wet air and other fluids cannot be considered. Moreover, the pre processor format of FLUENT is closed, which can only be suitable for fluent, and the pre processor ICEM of CFX has rich output formats< I've used CFX for a long time, and occasionally used fluent. I know that CFX has some shortcomings, and I also know that fluent is strong in some aspects.
1. There is only one kind of full implicit solver in CFX, and there are three kinds of fluent: progressive, full explicit and full implicit.
although CFX has less iteration, it consumes a lot of memory.
2, There are many unknown functions in the UDF (user Fortran in CFX) of CFX, so it is not easy to develop complex models. The UDF (in C language) of fluent can provide relatively complete information query< The GUI of CFX is really better than that of fluent, with good pre-processing and post-processing, and good coordination. Fluent just doesn't focus on the improvement of GUI, but it can achieve the same function. Just be used to it. The focus of CFD code is to avoid mistakes and misunderstandings. Does code developer rece CFD code error as much as possible!, GUI friendliness is not the key point. Basically, the accuracy of solution has a lot to do with the user's skill. For the same software and the same problem, some people solve it wrong and some are OK.
5. There are many users of the two kinds of software, and it is not easy to integrate them into one, but they may complement each other and improve at the same time.
6, The latest academic or instry research results will probably be reflected in the solver models, which is similar.
- --- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -. The efficiency of Yang Cheng calculated by these two softwares is almost the same, and the difference is 5%. This is already very big. Why? The torque calculated by FLUENT is 880, while the torque calculated by CFX is 850. It is because the torque difference is so much that the efficiency will be so poor. Why are the two CFD softwares so different when calculating the same pump? I heard some people say that CFX is more suitable for rotating machinery. Is that so? Is CFX more accurate than fluent? I hope you can give me an answer
whiz 2013-09-06 17:49
the difference of 5% between the two software results is not big<
z41906957 2013-09-13 22:56
how big is it
qianzd 2013-09-26 11:55
check your torque calculation surface, there should not be such a big gap
Rexxar 2013-09-27 03:07
5% is acceptable, if there are experimental data, compare with the actual test, In my previous experience of calculating pumps and turbines, the efficiency of FLUENT is always slightly lower than that of the experiment, while CFX is higher than that of fluent
in fact, the result of FLUENT is more conservative, and the characteristic curves calculated by the two softwares are similar
but the engineers feel that the efficiency of numerical calculation should be higher than that of the experiment It makes people think that CFX works well
and a series of software has been developed for CFX of rotating machinery for a long time, which is very convenient from pre-processing to post-processing, which also makes people in this field tend to use it
now that both of them are mastered by ANSYS, the difference should be smaller
Tianma sk 2013-09-28 11:32
listen to what you say, that is, the CF for water pump If x is calculated, the result is the closest to the experimental result? In other words, it is better to use CFX for water pump
turbulence 2013-09-30 21:04
What about grid independence? Is the model strictly consistent? Is the numerical format consistent<
Rexxar 2013-10-08 16:30
take a look at the suggestions on the sixth floor
the accuracy of the calculation results needs to be compared, and the experimental results or the recognized calculation results
I think CFX is more convenient to operate, and the calculation is good near the design condition, but some off design conditions are not very good, It depends on which one you choose.
in addition, it's not reliable to only rely on numerical calculation to obtain accurate performance parameters, whether it's fluent or CFX
5. CFD is the abbreviation of computational fluid dynamic. Both fluent and CFX are CFD software. The strength of CFX lies in rotating machinery, and fluent is the most widely used.
6. Using two-dimensional graphics and quarter circle as analysis, the line of the cut interface position is symmetrically constrained, and then loaded to solve
after the solution is completed, the deformation result is displayed, and then there is the option to display the symmetry mode in plotsctrl. After setting, you can see the desired deformation result
this is definitely related to what you need to do. The most important feature of ANSYS is that you can get a result by giving it a condition. Sometimes the result is good, but it would be miserable to write a paper. First, you must understand what you need to do, the meaning of all the parameters, what to do and what to expect from the result, and then push back according to the expected result, Let's see what kind of boundary conditions and initial values we need. In fact, the simulation is the same as the experiment.
after the solution is completed, the deformation result is displayed, and then there is the option to display the symmetry mode in plotsctrl. After setting, you can see the desired deformation result
this is definitely related to what you need to do. The most important feature of ANSYS is that you can get a result by giving it a condition. Sometimes the result is good, but it would be miserable to write a paper. First, you must understand what you need to do, the meaning of all the parameters, what to do and what to expect from the result, and then push back according to the expected result, Let's see what kind of boundary conditions and initial values we need. In fact, the simulation is the same as the experiment.
7. Web service is based on Web. First of all, you should have a web server, such as tomcat, to deploy CFX application on the web server
8. Grid capability (fluent
gambit is inferior to ICEM
CFD)
accuracy (fluent is not as good as CFX, the default difference scheme of CFX is second-order, but it is difficult for fluent to converge with the second-order scheme)
reliability (fluent is not as good as CFX)
by heart, CFX's coupled solver converges much faster than fluent.
gambit is inferior to ICEM
CFD)
accuracy (fluent is not as good as CFX, the default difference scheme of CFX is second-order, but it is difficult for fluent to converge with the second-order scheme)
reliability (fluent is not as good as CFX)
by heart, CFX's coupled solver converges much faster than fluent.
9. The advantages of CFX are abundant physical models and powerful functions. The finite volume discretization method based on finite element has high accuracy but slow calculation speed; There is a lack of fluent physical model, and there is no corresponding model for many problems. For example, each phase of multiphase flow cannot be multi-component, and multiphase flow composed of wet air and other fluids cannot be considered. Moreover, the pre processor format of FLUENT is closed, which can only be suitable for fluent, and the pre processor ICEM of CFX has rich output formats.
10. 1. Use the wsdl.exe command line tool. 2. Use the addwebreference menu option in VS.NET
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