I am doing research on atrial fibrillation and working on creating a 3D anatomy of the heart and some surrounding organs in Materialise MIMICS and 3-Matic in order to export my geometry to COMSOL in order to run simulations using the electric currents and electrostatics physics modules to test defibrillation thresholds. I have been working on preparing the geometry to create volume meshes within 3-matic for export to COMSOL. The issue I am having is when it comes to partitioning the geometry into the separate heart chambers and the surrounding organs. I am just a bit lost and am having issues finding the appropriate literature to read that is most pertinent to my issue. Any help would be appreciated. Thanks!
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Partitioning 3D Anatomical Geometry
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Comsol client for android
hi! whats comsol server in this app?
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Post-processing a model
Hello, I am a newbie to the COMSOL Multiphysics.
I am working on a porous Piezoelectric model and the simulation of the model was sucessful. The results of the von mises stress were acceptable. I want to obtain the value of the C11from elasticity matrix after simulation and want to comapre it with the Input C11 value(which was taken from bulk material) . I was unable to extract that value from the results. Is there anyway that I could possibly get that value from results.
Thanks.
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How to simulate Shape Memory behavior of Shape Memory Polymers?
Shape-memory polymers (SMPs) are polymeric smart materials that have the ability to return from a deformed state (temporary shape) to their original (permanent) shape induced by an external stimulus (trigger), such as temperature change. However, Unlike the Shape Memory Effect of Shape Memory Alloy(SMA), its Shape Memory behavior is base on the thermo-viscoelasticity of polymer materials.
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Parametric sweep with 3D imported from 2D
Hello,
I have a 3D object, made by importing a 2D object and rotating it. The 2D object has multiple parameters in a separate component. (I did this by following the video lecture of making 3D out of 2D geometry) I want to conduct a parametric sweep of parameters in the 2D object, which will finally change the 3D object shape. However when I run the sweep, all the results have same values. The 2D component has only geometry, and 3D has all others (materials, Physics, Mesh.) Is there a way of including this importing process in the sweep process? Thank you.
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Modeling electrochemistry system without electrochemistry module in Comsol
I am working on electrochemistry stuff but I am using the Comsol without electrochemistry module. How can I put equation to calculate impedance for my model based on various frequency. Also, how can I declare the effects of double layer capacitance, mass transport, and some relevant things. Thank you very much
Best,
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Could you please let me know what are the steps to follow to solve the 3D Helmholtz eigenvalue problem using Comsol software?
I'm a beginner in using COMSOL Multiphysics. I want to solve the 3D helmholtz eigenvalue with Dirichlet boundary condition using COMSOL. How to model COMSOL Multiphysics ? For example, how to compute the eigenfrequencies and the eigenmodes of 3D Helmholtz eigenvalue problem with Dirichlet boundary conditions using COMSOL ?
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Changing the resistivity of the Silicon Material
Hello,
I am fairly new to COMSOL and I am using Semiconductor physics module, I need to change the resistivity of my material Can you please let me know how to do that.
Thanks very much!
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Simulating transport of diluted species with a droplet inside the domain
Hi all, I'm simulating mixing of two streams with a droplet (please see the attached image), which means that I don't want COMSOL to solve tds inside the droplet (the black circle in the image.) I've tried some ideas but it doesn't seem right and two streams fall into the droplet actually. I have the level set module to track the droplet interface. Any ideas? Thanks, Milad
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Solving Linearized Euler Equation in frequency space using Weak Form PDE module
Hi,
I am trying to solve the Linearized Euler Equation (LEE) in frequency space using 'Weak form PDE' module. For 1-D, uniform mean quantity assumptions, the LEE is given by:
Momentum: rho_mean(iomegau+u_meanux)+px = 0 Energy: iomegap+u_meanpx+gammap_mean*ux = 0
If the BCs are rigid at both ends, the first theoretical eigen-frequency is given by:
f1 = c/(2L(1-M^2))
However, when I solve this problem with weak form PDE module, I got a different answer from the theoretical one, and could not find where I am wrong.
The attached files contain the ppt that summarized the procedure I took as well as the COMSOL file.
Thanks,
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Mass transport equation in moving geometry
Hi all, I have an immiscible droplet inside my mass transport domain, which means the mass transport phenomenon does not happen in the vicinity of this droplet and to the droplet. But I have mass transport to this droplet. How can I prevent mass transport to droplet assuming that I am solving level set for interface tracking. Thanks
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Boundary constraint
We are trying to solve FSI of a Submerged Floating Tunnel which is fixed at both ends. When i'm modelling with the pipe fixed at the Walls of the fluid domain, its not able to slove that. It always returns a message (Inconsistent Initial Values). Does the module interpret that as discontinous wall condition because that particular surface is being overridden from wall to fixed. When given as a surface constraint, it's not able to solve. When given as a volume or domain constraint it solves but gives back 0 displacement beacuse the body is fixed. But in the actual physical modelthe body is fixed only at the ends. How to overcome this issue?
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Why the torque in pm_motor graph
Dear all
Why I compute the torque of pm_motor, the data is under the axis? What makes the torque minus? The current of coils?
Regards
Joey
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AC/DC Module Permanent Magnet Motor(PMM) Simulation, Time-dependent, rotating magnetic machinery(rmm),Moving Mesh
Dear all
I am doing a simulation about pm-motor in version5.4. but I feel confused why the result of torque that it is below the coordinate. Whether should I define the coils in the motor?
Also, I want to ask a question that if I need to make the coils in the specified location, it can be activated. Should the variables can help me to handle this problem? Or should I use MATLAB to browse function to handle it?
Hope you can share idea with me.
Regards
Joey
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Adding interval from geometry toolbar
I am modelling the electrochemical impedance of a 1D li-ion battery, and would like to know how to add interval from the geometry toolbar. I am going through the tutorials by COMSOL for modelling impedance, but the geometry toolbar does not have "interval" in it.
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how to launch oblique gaussian beam in wave optics?
When I use the wave optics module scattered field formulation, I can select gaussian beam along either x or y direction. How can I launch a gaussian beam with arbitrary angle of incidence? (other than using user-defined fields or tilting the whole geometry)
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Effect of Large Scale Difference on Mesh
Hi Everyone,
I am modeling a 100 nm thick thin film on the glass substrate with size 25 mm x 25 mm x 1 mm (study: heat transfer in solids). However, when I mesh them a problem arises due to their differences in scale. What would you recommend me to do?
Thank you very much!
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Could I use comsol to simulation the Parity-time symmetry-broken Bragg grating
Its structure consists of a layer of PMMA doped with dye molecules and a layer of metal. The last layer of silica, where PMMA is the active layer, providing a gain to the structure.
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Velocity pressure coupling in comsol
Dear all,
I am a bit confused about the velocity-pressure coupling in COMSOL. The default solver sets in such a way that, for laminar case, velocity and pressure are solved in fully coupled manner. In case of turbuelnt flow, velocity and pressure are solved in one single segregated step. This means that even in case of turbuelnt flow, velocity and pressure are solved together in one step. I read more about the different velocity pressure coupling algorithm such as SIMPLE,PISO etc. to realize that the coupling algorithms are needed while solving velocity and pressure in segregated manner. Following document elaborates on different velocity-pressure coupling algorithms while solving these two variables in segreagated manner. https://www.aub.edu.lb/msfea/research/Documents/CFD-P15.pdf It is described that the segregated approach is needed to overcome the high computational effort for solving it with fully coupled approach.
In past, I had tried to manually segregate velocity and pressure. I wasn't able to get convergence there. Is it because the velocity-pressure coupling algorithms (SIMPLE, PISO etc) needed for the segregated approach are not available in COMSOL?
How exactly COMSOL is handling the fully coupled approach for velocity and pressure?
Thanks a lot.
Regards, Prajakta Nakate Delft University of Technology, The Netherlands.
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How to set polarization for a numeric port?
Hi all,
I'm a beginner in Comsol and I want to model a single mode silicon waveguide with SiO2 cladding (and something more complicated later) in 3D. I want to use numeric ports and I have to set a specific polarization of the incident light. How can this be done?
Thank you in advance for your answers...
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