Re: [Yade-dev] Open Source DEM with LAMMPS
Hi Feng, dear Yade community, @Feng: Thanks for the link to your homepage. It is interesting to know that somebody already did something similar :-) Btw: Is it correct that Yade is based on a shared memory approach? I think you and I should be using the same approach originated from Prof. Tsuji? Yes! 1. FVM size/particle size The simulations I did so far were with particle diameter in the same order of magnitude or smaller than the grid spacing. I did not extensively test particles that are much larger than the grid size because my flow problems did not involve such cases. But to my knowledge, this would lead to a) convergence issues and b) possibly malpredictions of the dragforce by standard drag correlations (Gidaspow, DiFelice,...) My maximum ratio cell spacing/particle diameter was ~1/1 which converged and matched the validation experiments well 2. The maximum particle number possible on a cluster It depends on what cluster you have :-) If you look at http://lammps.sandia.gov/bench.html#chute you fill find the rightmost dot in the left figure corresponding to 2 BILLION PARTICLES! 3. The parallel mechanism We are using MPI because we think that the code should be portable to clusters. We have a small cluster (~150 proc.) at our Institute, so for me it is a huge speed-up switching from my workstation to the cluster 4. What kind of problem/type of flow you use in your problem? Typical problems that we are using or intending to use CFD-DEM for is pneumatic conveying, fluidized bed, hopper discharge and die filling. 5. Is it easy to change/create new particle constitution laws for the solid phase? Yes, LAMMPS is written in the intention to be easily modified. A whole section of the documentation is dedicated to this: http://lammps.sandia.gov/doc/Section_modify.html I must admit that currently, LAMMPS is missing a feature to import granular walls from CAD. But I am working on this... 6. Effect of different drag equations I must admit that I did not extensively test that. Afaik, Gidaspow could lead to convergence problems as it is discontinuous in one point. Thus I also used DiFelice but did not find much difference I should add that the simulation experience I am talking about was with a EDEm-FLUENT coupling that I wrote myself. The LammpsFoam is now in beta, and this fluidized bed configuration http://lammps.sandia.gov/movies/gran_openfoam.avi is the only case that we calculated with LammpsFoam so far. @Feng: It would be nice to know what answer you would give to these 6 questions! Thanks and regards, Christoph --- Von: Feng Chen [mailto:fch...@utk.edu] Gesendet: Donnerstag, 08. Oktober 2009 02:18 An: kl...@fluidmech.mechatronik.uni-linz.ac.at; yade-dev@lists.launchpad.net; yade-us...@lists.launchpad.net Betreff: RE: [Yade-dev] Open Source DEM with LAMMPS Hi, Christoph Kloss: I am so glad to see there is another code for DEM-CFD coupling since this has been my PhD topic, I also coupled YADE with OpenFOAM: http://fchen3.googlepages.com/discreteelementmethod I think you and I should be using the same approach originated from Prof. Tsuji? I would be very like to discuss some of the details with you, such as: 1. FVM size/particle size 2. The maximum particle number possible on a cluster 3. The parallel mechanism 4. What kind of problem/type of flow you use in your problem? 5. Is it easy to change/create new particle constitution laws for the solid phase? 6. Effect of different drag equations etc. Thank you for sharing your experience with us!!! Feng Chen -Original Message- From: yade-dev-bounces+fchen3=utk@lists.launchpad.net on behalf of Christoph Kloss Sent: Wed 10/7/2009 6:11 AM To: yade-dev@lists.launchpad.net; yade-us...@lists.launchpad.net Subject: [Yade-dev] Open Source DEM with LAMMPS Dear yade users and developers, I would like to bring the DEM capabilities of LAMMPS to your attention. LAMMPS is an open source molecular dynamics code that also provides possibilities for DEM simulations (thanks to algorithmic and physical analogies). LAMMPS is on the open source market since the mid90s. It is thus quite mature, very fast and provides excellent documentation. Please refer to the homepage http://lammps.sandia.gov/ for download and documentation. For some simulation examples, please refer to http://lammps.sandia.gov/movies.html#dem The final movie ( http://lammps.sandia.gov/movies/gran_openfoam.avi ) shows a new capability that my colleague Christoph Goniva and I have developed to perform CFD-DEM simulations by coupling LAMMPS to the OpenFoam computational fluid dynamics (CFD) package. This allows us to run CFD-DEM simulations on clusters using MPI parallelism. Some more videos and sample input scripts can be found at http://fluid.jku.at/hp/index.php?option=com_docmantask=cat_viewgid=168 LAMMPS is written in C++ and very easy to modify. If you are interested in LAMMPS, you
Re: [Yade-dev] Open Source DEM with LAMMPS
Hi, Feng, I was wondering : what is the situation now regarding the integration of your work in the current bzr version? I remember you planned that. If it is operational, we can plan making comparisons with another FVM-DEM coupling Emanuele Catalano is developping now. Bruno Chen, Feng a écrit : Hi, Christoph Kloss: I am so glad to see there is another code for DEM-CFD coupling since this has been my PhD topic, I also coupled YADE with OpenFOAM: http://fchen3.googlepages.com/discreteelementmethod I think you and I should be using the same approach originated from Prof. Tsuji? I would be very like to discuss some of the details with you, such as: 1. FVM size/particle size 2. The maximum particle number possible on a cluster 3. The parallel mechanism 4. What kind of problem/type of flow you use in your problem? 5. Is it easy to change/create new particle constitution laws for the solid phase? 6. Effect of different drag equations etc. Thank you for sharing your experience with us!!! Feng Chen -Original Message- From: yade-dev-bounces+fchen3=utk@lists.launchpad.net on behalf of Christoph Kloss Sent: Wed 10/7/2009 6:11 AM To: yade-dev@lists.launchpad.net; yade-us...@lists.launchpad.net Subject: [Yade-dev] Open Source DEM with LAMMPS Dear yade users and developers, I would like to bring the DEM capabilities of LAMMPS to your attention. LAMMPS is an open source molecular dynamics code that also provides possibilities for DEM simulations (thanks to algorithmic and physical analogies). LAMMPS is on the open source market since the mid90s. It is thus quite mature, very fast and provides excellent documentation. Please refer to the homepage http://lammps.sandia.gov/ for download and documentation. For some simulation examples, please refer to http://lammps.sandia.gov/movies.html#dem The final movie ( http://lammps.sandia.gov/movies/gran_openfoam.avi ) shows a new capability that my colleague Christoph Goniva and I have developed to perform CFD-DEM simulations by coupling LAMMPS to the OpenFoam computational fluid dynamics (CFD) package. This allows us to run CFD-DEM simulations on clusters using MPI parallelism. Some more videos and sample input scripts can be found at http://fluid.jku.at/hp/index.php?option=com_docmantask=cat_viewgid=168 http://fluid.jku.at/hp/index.php?option=com_docmantask=cat_viewgid=168 LAMMPS is written in C++ and very easy to modify. If you are interested in LAMMPS, you are welcome to contact me! I would be happy if YADE and LAMMPS could profit from each other. Kind regards from Austria, Christoph Kloss Dipl.-Ing. Christoph Kloss Christian-Doppler Laboratory on Particulate Flow Modelling Institute of Fluid Mechanics and Heat Transfer Johannes Kepler University, Altenbergerstrasse 69, A-4040 Linz/Austria e-mail: christoph.kl...@jku.at phone: +43-(0)732-2468-6476 fax: +43-(0)732-2468-6462 web: fluid.jku.at --- ___ Mailing list: https://launchpad.net/~yade-dev https://launchpad.net/%7Eyade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev https://launchpad.net/%7Eyade-dev More help : https://help.launchpad.net/ListHelp ___ Mailing list: https://launchpad.net/~yade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp -- ___ Chareyre Bruno Maître de Conférences Grenoble INP Laboratoire 3SR - bureau E145 BP 53 - 38041, Grenoble cedex 9 - France Tél : 33 4 56 52 86 21 Fax : 33 4 76 82 70 43 ___ Mailing list: https://launchpad.net/~yade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp
Re: [Yade-dev] Open Source DEM with LAMMPS
Hi, Bruno: I have to admit honestly that I almost got no time to let the yade.0.11.1 version to work with the current bzr (even did not have bzr installed), and I have to say sorry that currently my time that can be spend on DEM and Linux is very very limited (only after work), so after the fluid solver issue (currently still having big trouble with the porosity calculation) is solved I would like to release it in original yade.0.11.1 version form. I wonder what kind of problem Emanuele Catalano is trying to solve? BTW: I tested yade.svn1943 last month on my laptop, my feeling is that compiling the svn1943 takes much longer time and consumes more resource on my laptop even for a incremental build which is a little bit frustrating :-) Feng -Original Message- From: yade-dev-bounces+fchen3=utk@lists.launchpad.net on behalf of Bruno Chareyre Sent: Thu 10/8/2009 5:48 AM To: yade-dev@lists.launchpad.net; demfl...@lists.launchpad.net Subject: Re: [Yade-dev] Open Source DEM with LAMMPS Hi, Feng, I was wondering : what is the situation now regarding the integration of your work in the current bzr version? I remember you planned that. If it is operational, we can plan making comparisons with another FVM-DEM coupling Emanuele Catalano is developping now. Bruno Chen, Feng a écrit : Hi, Christoph Kloss: I am so glad to see there is another code for DEM-CFD coupling since this has been my PhD topic, I also coupled YADE with OpenFOAM: http://fchen3.googlepages.com/discreteelementmethod I think you and I should be using the same approach originated from Prof. Tsuji? I would be very like to discuss some of the details with you, such as: 1. FVM size/particle size 2. The maximum particle number possible on a cluster 3. The parallel mechanism 4. What kind of problem/type of flow you use in your problem? 5. Is it easy to change/create new particle constitution laws for the solid phase? 6. Effect of different drag equations etc. Thank you for sharing your experience with us!!! Feng Chen -Original Message- From: yade-dev-bounces+fchen3=utk@lists.launchpad.net on behalf of Christoph Kloss Sent: Wed 10/7/2009 6:11 AM To: yade-dev@lists.launchpad.net; yade-us...@lists.launchpad.net Subject: [Yade-dev] Open Source DEM with LAMMPS Dear yade users and developers, I would like to bring the DEM capabilities of LAMMPS to your attention. LAMMPS is an open source molecular dynamics code that also provides possibilities for DEM simulations (thanks to algorithmic and physical analogies). LAMMPS is on the open source market since the mid90s. It is thus quite mature, very fast and provides excellent documentation. Please refer to the homepage http://lammps.sandia.gov/ for download and documentation. For some simulation examples, please refer to http://lammps.sandia.gov/movies.html#dem The final movie ( http://lammps.sandia.gov/movies/gran_openfoam.avi ) shows a new capability that my colleague Christoph Goniva and I have developed to perform CFD-DEM simulations by coupling LAMMPS to the OpenFoam computational fluid dynamics (CFD) package. This allows us to run CFD-DEM simulations on clusters using MPI parallelism. Some more videos and sample input scripts can be found at http://fluid.jku.at/hp/index.php?option=com_docmantask=cat_viewgid=168 http://fluid.jku.at/hp/index.php?option=com_docmantask=cat_viewgid=168 LAMMPS is written in C++ and very easy to modify. If you are interested in LAMMPS, you are welcome to contact me! I would be happy if YADE and LAMMPS could profit from each other. Kind regards from Austria, Christoph Kloss Dipl.-Ing. Christoph Kloss Christian-Doppler Laboratory on Particulate Flow Modelling Institute of Fluid Mechanics and Heat Transfer Johannes Kepler University, Altenbergerstrasse 69, A-4040 Linz/Austria e-mail: christoph.kl...@jku.at phone: +43-(0)732-2468-6476 fax: +43-(0)732-2468-6462 web: fluid.jku.at --- ___ Mailing list: https://launchpad.net/~yade-dev https://launchpad.net/%7Eyade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev https://launchpad.net/%7Eyade-dev More help : https://help.launchpad.net/ListHelp ___ Mailing list: https://launchpad.net/~yade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp -- ___ Chareyre Bruno Maître de Conférences Grenoble INP Laboratoire 3SR - bureau E145 BP 53 - 38041, Grenoble cedex 9 - France Tél : 33 4 56 52 86 21 Fax : 33 4 76 82 70 43
Re: [Yade-dev] Open Source DEM with LAMMPS
Hi, Chris: Thanks for your answer, I would like to share my experience on the issues below: Btw: Is it correct that Yade is based on a shared memory approach? ///Vaclav has answered that problem, the performance increase on the parallel issue using OpenMP seems to be limited. 1. FVM size/particle size The simulations I did so far were with particle diameter in the same order of magnitude or smaller than the grid spacing. I did not extensively test particles that are much larger than the grid size because my flow problems did not involve such cases. But to my knowledge, this would lead to a) convergence issues and b) possibly malpredictions of the dragforce by standard drag correlations (Gidaspow, DiFelice,...) My maximum ratio cell spacing/particle diameter was ~1/1 which converged and matched the validation experiments well ///As I know the minimum FVM size must be larger than the particle size, when the FVM size is close to particle size, will lead to porosity value singularity, which will in turn, cause instability in N-S continuity solution (This is also mentioned in PFC2D fluid option's manual) 2. The maximum particle number possible on a cluster It depends on what cluster you have :-) If you look at http://lammps.sandia.gov/bench.html#chute you fill find the rightmost dot in the left figure corresponding to 2 BILLION PARTICLES! ///In my thesis I used 8200 particles on a workstation, I wish I could use at 10^6 level. 3. The parallel mechanism We are using MPI because we think that the code should be portable to clusters. We have a small cluster (~150 proc.) at our Institute, so for me it is a huge speed-up switching from my workstation to the cluster ///Same answer as the shared memory, I met the bottle neck. 4. What kind of problem/type of flow you use in your problem? Typical problems that we are using or intending to use CFD-DEM for is pneumatic conveying, fluidized bed, hopper discharge and die filling. ///I use this in the chromatography column packing, stress-strain caused by fluid drag, sheet pile, seepage in dam 5. Is it easy to change/create new particle constitution laws for the solid phase? Yes, LAMMPS is written in the intention to be easily modified. A whole section of the documentation is dedicated to this: http://lammps.sandia.gov/doc/Section_modify.html I must admit that currently, LAMMPS is missing a feature to import granular walls from CAD. But I am working on this... ///I ask this because I am working on visco-elastic model (Burgers, Maxwell etc which can be used in asphalt concrete) and some other non-linear models 6. Effect of different drag equations I must admit that I did not extensively test that. Afaik, Gidaspow could lead to convergence problems as it is discontinuous in one point. Thus I also used DiFelice but did not find much difference ///I used Ergun's (1952) equation, there is a more detailed comparison in MFix about different drag equations I should add that the simulation experience I am talking about was with a EDEm-FLUENT coupling that I wrote myself. The LammpsFoam is now in beta, and this fluidized bed configuration http://lammps.sandia.gov/movies/gran_openfoam.avi is the only case that we calculated with LammpsFoam so far. ///YADE-OpenFOAM has also been in an alpha-beta status for a long time, some portion of the code (especially coupling part) is so crappy that I even feel shame to release it:-P, although I have been working on this for 2 more years, hehe :-) ___ Mailing list: https://launchpad.net/~yade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp
[Yade-dev] Open Source DEM with LAMMPS
Dear yade users and developers, I would like to bring the DEM capabilities of LAMMPS to your attention. LAMMPS is an open source molecular dynamics code that also provides possibilities for DEM simulations (thanks to algorithmic and physical analogies). LAMMPS is on the open source market since the mid90s. It is thus quite mature, very fast and provides excellent documentation. Please refer to the homepage http://lammps.sandia.gov/ for download and documentation. For some simulation examples, please refer to http://lammps.sandia.gov/movies.html#dem The final movie ( http://lammps.sandia.gov/movies/gran_openfoam.avi ) shows a new capability that my colleague Christoph Goniva and I have developed to perform CFD-DEM simulations by coupling LAMMPS to the OpenFoam computational fluid dynamics (CFD) package. This allows us to run CFD-DEM simulations on clusters using MPI parallelism. Some more videos and sample input scripts can be found at http://fluid.jku.at/hp/index.php?option=com_docmantask=cat_viewgid=168 LAMMPS is written in C++ and very easy to modify. If you are interested in LAMMPS, you are welcome to contact me! I would be happy if YADE and LAMMPS could profit from each other. Kind regards from Austria, Christoph Kloss Dipl.-Ing. Christoph Kloss Christian-Doppler Laboratory on Particulate Flow Modelling Institute of Fluid Mechanics and Heat Transfer Johannes Kepler University, Altenbergerstrasse 69, A-4040 Linz/Austria e-mail: christoph.kl...@jku.at phone: +43-(0)732-2468-6476 fax: +43-(0)732-2468-6462 web: fluid.jku.at --- ___ Mailing list: https://launchpad.net/~yade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp
Re: [Yade-dev] Open Source DEM with LAMMPS
Hi, Christoph Kloss: I am so glad to see there is another code for DEM-CFD coupling since this has been my PhD topic, I also coupled YADE with OpenFOAM: http://fchen3.googlepages.com/discreteelementmethod I think you and I should be using the same approach originated from Prof. Tsuji? I would be very like to discuss some of the details with you, such as: 1. FVM size/particle size 2. The maximum particle number possible on a cluster 3. The parallel mechanism 4. What kind of problem/type of flow you use in your problem? 5. Is it easy to change/create new particle constitution laws for the solid phase? 6. Effect of different drag equations etc. Thank you for sharing your experience with us!!! Feng Chen -Original Message- From: yade-dev-bounces+fchen3=utk@lists.launchpad.net on behalf of Christoph Kloss Sent: Wed 10/7/2009 6:11 AM To: yade-dev@lists.launchpad.net; yade-us...@lists.launchpad.net Subject: [Yade-dev] Open Source DEM with LAMMPS Dear yade users and developers, I would like to bring the DEM capabilities of LAMMPS to your attention. LAMMPS is an open source molecular dynamics code that also provides possibilities for DEM simulations (thanks to algorithmic and physical analogies). LAMMPS is on the open source market since the mid90s. It is thus quite mature, very fast and provides excellent documentation. Please refer to the homepage http://lammps.sandia.gov/ for download and documentation. For some simulation examples, please refer to http://lammps.sandia.gov/movies.html#dem The final movie ( http://lammps.sandia.gov/movies/gran_openfoam.avi ) shows a new capability that my colleague Christoph Goniva and I have developed to perform CFD-DEM simulations by coupling LAMMPS to the OpenFoam computational fluid dynamics (CFD) package. This allows us to run CFD-DEM simulations on clusters using MPI parallelism. Some more videos and sample input scripts can be found at http://fluid.jku.at/hp/index.php?option=com_docmantask=cat_viewgid=168 LAMMPS is written in C++ and very easy to modify. If you are interested in LAMMPS, you are welcome to contact me! I would be happy if YADE and LAMMPS could profit from each other. Kind regards from Austria, Christoph Kloss Dipl.-Ing. Christoph Kloss Christian-Doppler Laboratory on Particulate Flow Modelling Institute of Fluid Mechanics and Heat Transfer Johannes Kepler University, Altenbergerstrasse 69, A-4040 Linz/Austria e-mail: christoph.kl...@jku.at phone: +43-(0)732-2468-6476 fax: +43-(0)732-2468-6462 web: fluid.jku.at --- ___ Mailing list: https://launchpad.net/~yade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp ___ Mailing list: https://launchpad.net/~yade-dev Post to : yade-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp
