# Latest **URL:** https://bempp.discourse.group/latest.md?page=1 [Latest](https://bempp.discourse.group/latest.md) · [Categories](https://bempp.discourse.group/categories.md) **Page:** 2 --- ## [Requesting help: Issues Installing exafmm-t for BEMPP Acoustic Simulations](https://bempp.discourse.group/t/requesting-help-issues-installing-exafmm-t-for-bempp-acoustic-simulations/294)
**Author:** [@Kevin](https://bempp.discourse.group/u/Kevin)\ **Replies:** 0\ **Last updated:** [11 November 2024 14:53 UTC](https://bempp.discourse.group/t/requesting-help-issues-installing-exafmm-t-for-bempp-acoustic-simulations/294 "2024-11-11T14:53:58Z")
Hello Everyone, I’m currently working on an acoustic simulation using BEMPP, where I’m dealing with a mesh that contains 110,000 nodes. Initially, I attempted to use a dense assembler with the following command: double… --- ## [Dof transformations not supported by bempp-cl](https://bempp.discourse.group/t/dof-transformations-not-supported-by-bempp-cl/250)
**Author:** [@Gabriel](https://bempp.discourse.group/u/Gabriel)\ **Replies:** 1\ **Last updated:** [29 October 2024 14:22 UTC](https://bempp.discourse.group/t/dof-transformations-not-supported-by-bempp-cl/250 "2024-10-29T14:22:56Z")
Hello, I am concerned with Maxwell problems and was very impressed by BEMpp capabilities described in the Scroggs & al. 2017 paper (Redirecting). The tutorials maxwell\_dielectric and maxwell\_screen in Jupyter notebooks … --- ## [Not possible to install bempp or bempp cl on Windows 11](https://bempp.discourse.group/t/not-possible-to-install-bempp-or-bempp-cl-on-windows-11/288)
**Author:** [@Nikolay](https://bempp.discourse.group/u/Nikolay)\ **Replies:** 4\ **Last updated:** [12 October 2024 14:06 UTC](https://bempp.discourse.group/t/not-possible-to-install-bempp-or-bempp-cl-on-windows-11/288 "2024-10-12T14:06:34Z")
Hi is there any way to install bempp-cl or Bempp 3.3.4 on Windows 11? All my attemps failed. For example by using anaconda I tried: conda config --add channels conda-forge conda config --set channel\_priority strict … --- ## [Problems in space creation from imported grid](https://bempp.discourse.group/t/problems-in-space-creation-from-imported-grid/292)
**Author:** [@diego](https://bempp.discourse.group/u/diego)\ **Replies:** 1\ **Last updated:** [11 October 2024 19:31 UTC](https://bempp.discourse.group/t/problems-in-space-creation-from-imported-grid/292 "2024-10-11T19:31:21Z")
Hello, I am new to bempp. I created a grid (using a convex hull algorthm) outside bempp environment and imported it. grid.plot() looks fine. However, when running A0\_int = multitrace\_operator(grid, k\_int, epsilon\_r=epsi… --- ## [Derivations of equations in mscroggs bempp-acoustic-tutorials](https://bempp.discourse.group/t/derivations-of-equations-in-mscroggs-bempp-acoustic-tutorials/278)
**Author:** [@Kevin](https://bempp.discourse.group/u/Kevin)\ **Replies:** 1\ **Last updated:** [11 October 2024 18:59 UTC](https://bempp.discourse.group/t/derivations-of-equations-in-mscroggs-bempp-acoustic-tutorials/278 "2024-10-11T18:59:17Z")
Hello Everyone, Does anybody know where I can find detailed derivations of equations involving double layer boundary operators used in bempp-acoustic-tutorials by mscroggs? --- ## [Velocity field with phase](https://bempp.discourse.group/t/velocity-field-with-phase/245)
**Author:** [@soundintubes](https://bempp.discourse.group/u/soundintubes)\ **Replies:** 3\ **Last updated:** [7 October 2024 10:24 UTC](https://bempp.discourse.group/t/velocity-field-with-phase/245 "2024-10-07T10:24:40Z")
Hello, apologies in advance but I am an engineer not a mathematician(!) I’m working on an acoustics problem of a cube with one face radiating. I based it on this tutorial: https://nbviewer.org/github/mscroggs/bempp-aco… --- ## [OpenCl in Windows 10](https://bempp.discourse.group/t/opencl-in-windows-10/165)
**Author:** [@marc.jofre](https://bempp.discourse.group/u/marc.jofre)\ **Replies:** 1\ **Last updated:** [30 September 2024 09:39 UTC](https://bempp.discourse.group/t/opencl-in-windows-10/165 "2024-09-30T09:39:27Z")
Hi, I have managed to install OpenCL in Windows 10 and Bempp detecting it on Jupyter Python. I installed the following drivers: Intel® CPU Runtime for OpenCL™ Applications 18.1 for Windows\* OS (64bit or 32bit) From: O… --- ## [Issues encountered with grid output in the 0.3.1 version](https://bempp.discourse.group/t/issues-encountered-with-grid-output-in-the-0-3-1-version/284)
**Author:** [@S.L](https://bempp.discourse.group/u/S.L)\ **Replies:** 2\ **Last updated:** [24 September 2024 03:35 UTC](https://bempp.discourse.group/t/issues-encountered-with-grid-output-in-the-0-3-1-version/284 "2024-09-24T03:35:29Z")
Hello! I am delighted to have discovered bempp as an invaluable aid for my computations. But, when using 0.3.1, upon completing calculations and attempting to export the grid, an error is encountered: Running this oper… --- ## [Integrating function of surface normals](https://bempp.discourse.group/t/integrating-function-of-surface-normals/280)
**Author:** [@Arne](https://bempp.discourse.group/u/Arne)\ **Replies:** 1\ **Last updated:** [11 September 2024 15:27 UTC](https://bempp.discourse.group/t/integrating-function-of-surface-normals/280 "2024-09-11T15:27:06Z")
I am trying to compute various quantities from the scattering amplitude, in the setting of acoustic scattering from an obstacle \\Omega with Dirichlet boundary conditions. One way to compute the scattering amplitude (cf.… --- ## [External BEM theory explanation help](https://bempp.discourse.group/t/external-bem-theory-explanation-help/172)
**Author:** [@jungleb77](https://bempp.discourse.group/u/jungleb77)\ **Replies:** 1\ **Last updated:** [27 August 2024 12:29 UTC](https://bempp.discourse.group/t/external-bem-theory-explanation-help/172 "2024-08-27T12:29:23Z")
So I’ve read through BEM theory several times over several years now and there’s something that always bugs me. Perhaps one of you has an intuitive explanation. The Green’s function for acoustics is simple to understand… --- ## [Looking for Paid Tutoring Services for Bempp](https://bempp.discourse.group/t/looking-for-paid-tutoring-services-for-bempp/273)
**Author:** [@Kevin](https://bempp.discourse.group/u/Kevin)\ **Replies:** 1\ **Last updated:** [12 August 2024 16:49 UTC](https://bempp.discourse.group/t/looking-for-paid-tutoring-services-for-bempp/273 "2024-08-12T16:49:08Z")
Hi everyone, I hope you are all doing well. My name is Kevin, and I am studying masters in computational engineering. I am currently looking to learn Bempp for my thesis on Acoustic simulation and am seeking someone wh… --- ## [Logging/debugging core](https://bempp.discourse.group/t/logging-debugging-core/276)
**Author:** [@soundintubes](https://bempp.discourse.group/u/soundintubes)\ **Replies:** 0\ **Last updated:** [31 July 2024 17:53 UTC](https://bempp.discourse.group/t/logging-debugging-core/276 "2024-07-31T17:53:21Z")
I’ve found bempp.api.enable\_console\_logging, which gives some useful output from GMRES. But what I’m really looking for is a more verbose debug log, so that when I run something like: helmholtz.double\_layer(… I can se… --- ## [Kifmm for vector fields?](https://bempp.discourse.group/t/kifmm-for-vector-fields/275)
**Author:** [@mvernacc](https://bempp.discourse.group/u/mvernacc)\ **Replies:** 2\ **Last updated:** [17 July 2024 19:17 UTC](https://bempp.discourse.group/t/kifmm-for-vector-fields/275 "2024-07-17T19:17:14Z")
Can kifmm be used for calculations where the pairwise kernel maps a vector to a vector, instead of a scalar to a scalar? I see an example of calculating the scalar electric potential at many observation points from many … --- ## [Calculate the double-layer potential using a function obtained from fenicsx](https://bempp.discourse.group/t/calculate-the-double-layer-potential-using-a-function-obtained-from-fenicsx/268)
**Author:** [@Mk2020](https://bempp.discourse.group/u/Mk2020)\ **Replies:** 1\ **Last updated:** [12 June 2024 20:44 UTC](https://bempp.discourse.group/t/calculate-the-double-layer-potential-using-a-function-obtained-from-fenicsx/268 "2024-06-12T20:44:58Z")
Hi, I have computed a flow using fenicsx and would like to utilize Bempp to calculate the BEM component. Although I have reviewed the example, I still find the process unclear. Basically, I would like to calculate the … --- ## [Bempp+plotly+dash compiled with pyinstaller does not launch due to gmsh dependencye](https://bempp.discourse.group/t/bempp-plotly-dash-compiled-with-pyinstaller-does-not-launch-due-to-gmsh-dependencye/269)
**Author:** [@FrOl](https://bempp.discourse.group/u/FrOl)\ **Replies:** 0\ **Last updated:** [5 June 2024 07:25 UTC](https://bempp.discourse.group/t/bempp-plotly-dash-compiled-with-pyinstaller-does-not-launch-due-to-gmsh-dependencye/269 "2024-06-05T07:25:18Z")
Hi I want to make an exe file using pyinstaller from a Dash app using bempp and plotly. Due to gmsh dependency the app does not launch. Is there a proper way to proceed with pyinstaller or bempp to fix this? --- ## [Solve BIE of Stokes equation](https://bempp.discourse.group/t/solve-bie-of-stokes-equation/267)
**Author:** [@celebi](https://bempp.discourse.group/u/celebi)\ **Replies:** 2\ **Last updated:** [3 June 2024 13:41 UTC](https://bempp.discourse.group/t/solve-bie-of-stokes-equation/267 "2024-06-03T13:41:48Z")
Dear All, I’m wondering is there a way to assemble the discretized BIOs associated to Stokes equation? I looked up the documentations and it seems there are interfaces only for BIOs of Laplace, Helmholtz and Maxwell equ… --- ## [Accounting for ground effects in acoustic radiation](https://bempp.discourse.group/t/accounting-for-ground-effects-in-acoustic-radiation/264)
**Author:** [@Chakib](https://bempp.discourse.group/u/Chakib)\ **Replies:** 1\ **Last updated:** [16 May 2024 14:31 UTC](https://bempp.discourse.group/t/accounting-for-ground-effects-in-acoustic-radiation/264 "2024-05-16T14:31:41Z")
Dear BEMPP Community, I’m working on an acoustic radiation problem involving a vibrating disc, and I need to consider ground effects in my model. I noticed on the forum that the half-space assumption isn’t supported in … --- ## [Axisymmetric simulations for a neumann problem](https://bempp.discourse.group/t/axisymmetric-simulations-for-a-neumann-problem/258)
**Author:** [@speetpeet](https://bempp.discourse.group/u/speetpeet)\ **Replies:** 5\ **Last updated:** [26 April 2024 21:04 UTC](https://bempp.discourse.group/t/axisymmetric-simulations-for-a-neumann-problem/258 "2024-04-26T21:04:16Z")
For a horn loudspeaker radiation problem in bempp I’d like to speed up simulations. As the boundaries are rigid and axisymmetric i’d like to simulate in 2d instead of 3d, drastically reducing the complexity of the proble… --- ## [Delta gap in dipole antenna](https://bempp.discourse.group/t/delta-gap-in-dipole-antenna/256)
**Author:** [@AnthonyTSV](https://bempp.discourse.group/u/AnthonyTSV)\ **Replies:** 1\ **Last updated:** [26 April 2024 13:36 UTC](https://bempp.discourse.group/t/delta-gap-in-dipole-antenna/256 "2024-04-26T13:36:28Z")
Hello there! How would one simulate a dipole antenna with a delta gap, i.e. a gap between two cylinders connected with an edge, that is being excited? I created two cylinders with a gap connected with a line in gmsh. B… --- ## [How to export potential operator as matrix](https://bempp.discourse.group/t/how-to-export-potential-operator-as-matrix/202)
**Author:** [@Marco](https://bempp.discourse.group/u/Marco)\ **Replies:** 2\ **Last updated:** [26 April 2024 13:28 UTC](https://bempp.discourse.group/t/how-to-export-potential-operator-as-matrix/202 "2024-04-26T13:28:04Z")
Hi, I want to construct an “acoustic transfer matrix”, which maps source pressure on the boundary to the field points. Construction of the transfer matrix requires operator inverse on the boundary operator. Yes, I can c… --- ## [Burton-Miller formulation is not correct](https://bempp.discourse.group/t/burton-miller-formulation-is-not-correct/254)
**Author:** [@hellojxt](https://bempp.discourse.group/u/hellojxt)\ **Replies:** 1\ **Last updated:** [8 April 2024 09:23 UTC](https://bempp.discourse.group/t/burton-miller-formulation-is-not-correct/254 "2024-04-08T09:23:04Z")
I found that the Burton-Miller formulation yields higher errors compared to the standard boundary element equation in my test case. Can someone explain why this might be happening? Reproduction code: import bempp.api i… --- ## [TypeError: 'SumBlockedOperator' object is not subscriptable](https://bempp.discourse.group/t/typeerror-sumblockedoperator-object-is-not-subscriptable/237)
**Author:** [@gerard](https://bempp.discourse.group/u/gerard)\ **Replies:** 0\ **Last updated:** [27 February 2024 16:11 UTC](https://bempp.discourse.group/t/typeerror-sumblockedoperator-object-is-not-subscriptable/237 "2024-02-27T16:11:03Z")
Hello all, with BEMpp 0.3.1, when trying the snippets of figures 9 (preconditioned EFIE) and 13 (MFIE) extract from the 2017 amazing paper Redirecting. import numpy as np import bempp.api from bempp.api.operators.bound… --- ## [How can I determine the orientation of normals on a given grid?"](https://bempp.discourse.group/t/how-can-i-determine-the-orientation-of-normals-on-a-given-grid/235)
**Author:** [@Chayma](https://bempp.discourse.group/u/Chayma)\ **Replies:** 2\ **Last updated:** [26 February 2024 12:45 UTC](https://bempp.discourse.group/t/how-can-i-determine-the-orientation-of-normals-on-a-given-grid/235 "2024-02-26T12:45:11Z")
Hi all, I have a grid grid = bempp.api.shapes.sphere(r=0.5, origin=(0, 0, 0), h=0.2) and I want to obtain the swapped normals . Any help is highly appreciated. Thanks a lot! --- ## [Ways to define domains in \*.msh files](https://bempp.discourse.group/t/ways-to-define-domains-in-msh-files/223)
**Author:** [@TKaF](https://bempp.discourse.group/u/TKaF)\ **Replies:** 5\ **Last updated:** [27 January 2024 13:10 UTC](https://bempp.discourse.group/t/ways-to-define-domains-in-msh-files/223 "2024-01-27T13:10:34Z")
Dear community, i am interested to simulate acoustical radiation from a horn. I can model the horn (based on formulas / in a parametrical manner) and the membrane independently and covert it form point clouds to a mesh… --- ## [Error in barycentric refinement of order 1 P space](https://bempp.discourse.group/t/error-in-barycentric-refinement-of-order-1-p-space/227)
**Author:** [@Raphael](https://bempp.discourse.group/u/Raphael)\ **Replies:** 2\ **Last updated:** [22 January 2024 10:51 UTC](https://bempp.discourse.group/t/error-in-barycentric-refinement-of-order-1-p-space/227 "2024-01-22T10:51:05Z")
Dear Bempp team, I think there is an implementation error in the barycentric refinement of the order 1 P space in Bempp-cl 0.3.1. Calling bempp.api.space.scalar\_spaces.p1\_barycentric\_continuous\_function\_space(coarse\_spa… --- ## [Error in surface curl function](https://bempp.discourse.group/t/error-in-surface-curl-function/231)
**Author:** [@Raphael](https://bempp.discourse.group/u/Raphael)\ **Replies:** 0\ **Last updated:** [16 January 2024 08:22 UTC](https://bempp.discourse.group/t/error-in-surface-curl-function/231 "2024-01-16T08:22:49Z")
Dear Bempp team, I think there is an implementation error in the surface\_curl function of the bempp.api.space.FunctionSpace class in Bempp-cl 0.3.1. There are two input arguments missing in the returned numba\_surface\_cu… --- ## [The fem-bem couple code error using dolfinx](https://bempp.discourse.group/t/the-fem-bem-couple-code-error-using-dolfinx/230)
**Author:** [@jia](https://bempp.discourse.group/u/jia)\ **Replies:** 0\ **Last updated:** [16 January 2024 06:47 UTC](https://bempp.discourse.group/t/the-fem-bem-couple-code-error-using-dolfinx/230 "2024-01-16T06:47:39Z")
Hello everyone, I am following the tutorial for the latest fem-bem couple solver. When I was running such code, I got such error below, which is seems like the memory leak. I has used the valgrind and the result shows t… --- ## [Far-field scattering pattern for FEM-BEM coupling](https://bempp.discourse.group/t/far-field-scattering-pattern-for-fem-bem-coupling/225)
**Author:** [@Hassan](https://bempp.discourse.group/u/Hassan)\ **Replies:** 2\ **Last updated:** [13 January 2024 08:34 UTC](https://bempp.discourse.group/t/far-field-scattering-pattern-for-fem-bem-coupling/225 "2024-01-13T08:34:14Z")
Hi everyone, I want to use FEniCS together with Bempp to compute the far-field scattering pattern from a unit sphere. I modified " Simple FEM-BEM coupling for the Helmholtz equation with FEniCS" for a unite sphere and … --- ## [How can I define a MtE operator on a bounded plane?](https://bempp.discourse.group/t/how-can-i-define-a-mte-operator-on-a-bounded-plane/221)
**Author:** [@Yonglin](https://bempp.discourse.group/u/Yonglin)\ **Replies:** 1\ **Last updated:** [12 January 2024 14:53 UTC](https://bempp.discourse.group/t/how-can-i-define-a-mte-operator-on-a-bounded-plane/221 "2024-01-12T14:53:46Z")
I want to define a MtE operator T such that T(n × E) = n × H on Γ where Γ = { (x,y,0) | 0 \< x \< 1, 0 \< y \< 1}. (E, H) satisfies the homogeneous Maxwell equations in the upper space { z \> 0 }. How can I do this? --- ## [How can I use a bempp operator's tangential as a new operator?](https://bempp.discourse.group/t/how-can-i-use-a-bempp-operators-tangential-as-a-new-operator/217)
**Author:** [@zbl](https://bempp.discourse.group/u/zbl)\ **Replies:** 1\ **Last updated:** [26 October 2023 08:45 UTC](https://bempp.discourse.group/t/how-can-i-use-a-bempp-operators-tangential-as-a-new-operator/217 "2023-10-26T08:45:22Z")
The integral equation I want to solve is: lhs=0.5\*Id+cross(n,E) rhs=know The “cross()” above means the vector’s cross product, and the vector ‘n’ is the unit normal vector upon the surface of the target. Moreover, the… [Previous page](https://bempp.discourse.group/latest.md) [Next page](https://bempp.discourse.group/latest.md?page=2)