mathias
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Dear saida29,rnrnI am n ot really a Fortan expert. To speed up, can you please indicate the line where the velocity is finally computed, shorten the code and comment it.rnrnMathias
Have a look at: http://dx.doi.org/10.1063/1.1399290 rnrnMathias
Dear Shreyas,rnrn The function “”setOffset”” of “”BlockGeometry”” does not change the matrix itself. You need to create a new “”BlockGeometry”” and copy the data by hand. Yet, it is much easier to use the read function of the “”STLReader”” with an appropriate offset. rnrnMathias
Dear Shreyas,rnrn It is not working with “”blockGeometry.setNx ( some new nX)””. You can do it like this: rnrntemplate<typename T>rnvoid STLreader<T>::read(BlockGeometry3D &matrix, unsigned direction,rn unsigned voxelNumber, unsigned pad,rn double fraction, unsigned samples,rn unsigned offsetXN, unsigned offsetXP,rn unsigned offsetYN, unsigned offsetYP,rn unsigned offsetZN, unsigned offsetZP) const {rnrnrnwhere you distinguish between positive P and negative N direction. rnrnMathias
Dear Shreyas,rnrn1) You can define and an offset (cf. read function is stlReader.h) of constant size. In the next release we will have an extension for arbitrary offsets. It is not a big thing to program it in “stlRealer.h”.rn2) I am not sure that I have understood your question correctly. Actually the no. of cuboids is defined by the user.rnrnRegardsrnMathias
Dear Philipp,rnrn This depends on the contributions of OpenLB authors and users who are willing to share their work under GPL2 license. OpenLB is an open community – so everyone is invited to participate and share! Their names will be listed on the website. Interested friends of OpenLB can send an email to contact(a)openlb.net to be involved.rnrnMathiasrn rn
Dear Bolt,rnrn Depending on actual shape of the obstracle Bounce Back might just 1st order accurate. You will get better results if you refine the mesh and a better order with Bouzidi’s boundary conditions. We are currently working on Bouzidi’s boundary conditions.rnrnMathias
Dear Patrick,rnrn Please download release 1 of 0.7 if you have not done yet. Further, please send the Makefile.inc you are using to bug@openlb.net . I am using gcc 4.4.3 and openmpi and just tested this example which was working fine.rnrnMathias
Dear Bolt,rnrn The reason is the motivation behind Bounce Back: a particle moving towards the wall, coliding with it and being reflexted. So you can also include it in your step 3. It really depends on how you have implemented your LBM, e.g. if you a working with ghost cells.rnrnMathias
Dear Bolt,rnrn I would include it in the stream step.rnrnMathias
Dear both,rnrn Unfortunately I have no experience compiling OpenLB on a Windows system. Maybe there is a problem with included opose to “”boost”” files. You can try and remove the line “”src/external/boost “” in the file “”Makefile.inc””.rnrnMathias
Dear Atul,rnrn Compiling OpenLB using linux is quite easy. First you need to install a compiler like “”gnu gcc””, and also “”make””. Both is standard and probably already installed on your system. If you want to run OpenLB in parallel you also need to install “”mpi””. Then, go into one of the example folders and type “”make””. Then, OpenLB is compiling automatically. To run the example program type ./””program name””. You will also find our user guid helpful.rnrnBest regardsrnMathias
Dear Jay,rnrn Have a look at “”cylinder2d”” and “”cylinder3d””. There is an object in a tube. We have implemented Lagrangian particles recently. It is working well and we think of releasing them in one of the next releases. You can contact me directly if you want to know more -> info(at)openlb.net.rnrnMathias
Dear Jeff,rnrnat first I would try simple Bounce Back as boundary condition for all corners. I further recomment to have a look at papers of Michael Junk et al.. I remember some very helpful papers of him about that topic.rnrnMathias
The problem should be solved now. Thanks a lot for reporting!rnMathias