Comsol last time step is not converged

comsol last time step is not converged 2a 1 Reply Response spectrum analysis is a method to estimate the structural response to short, nondeterministic, transient dynamic events. I faced following error in comsol,in fsi simulation and time dependent. docx Report on Computer Homework 1 - Read online for free. " In May 2018, Comsol partnered with Samsung to trial a live 5G pilot network in Vilakazi Street in Soweto. For example: a normal time interval would be around 0. - Feature: Time-Dependent Solver 1 (sol1/t1) 4 Replies Last Post 6 mars 2017 à 12:05 UTC−5 I am working with COMSOL 5. Matrix is singular When encountered during time-dependent solution: the linear system matrix (which is a linear combination of the mass-, stiffness-, and possibly, damping 请问各位大侠,我用直流放电模块计算一个非常简单的模型,两个平板电极,一个接地,一个加-1000V电压,计算Ar气放电过程中电子和离子密度分布。 The last time step returned from the time-dependent solver is not to be trusted. A time-domain boundary condition has been recently proposed and has been implemented in a finite-difference time-domain solver using methods developed for computational aeroacoustics. 4 • numerical complexity of the cycle is reflected well by the time per cycle • convergence speed of F- and W-cycle are identical F- and W- converge faster than V-cycle • MG with V(2,1)-cycle usually is the fastest MG-solver (time to solve) • steady convergence speed for all cycles (first to last) • convergence speed is almost h-independent The procedure thereby is the same as described in the following paragraph. 5 hi i calculate inductive heating in comsol, when i define the coil with current of 120 A the comsol work without errors and when i define the coil with input of power=1200W (and i try smaller power) i get the error: - feature: time dependent solver 1 (sol1/t1) failed to find consistent initial values. 1 Feb 2018 Last time step is not converged. Examples of such events are earthquakes and shocks. How can i fix it? The study has been running more than 24 hours i can't re-do it easily. The amount of memory that is required to run a simulation is large and the execution time can be quite long for an individual simulation. warning: MUMPS allocation factor increased to 1. To mesh the two parts separately, the objects must be finalized by forming an assembly. For a Time Dependent study, from the Time list, select Automatic (the default) to use the solution for the last time, select First to use the first solution, select Last to use the last solution, select All to use all solutions from that study, select Interpolated to specify a time in the text field that opens and use the interpolated solution at that time, select Manual to use a specific Cons. Anyway. 5 seconds at intervals of 0. And are all your BC "smooth"--Good luck Ivar Hi Ivar, could you please explain a bit more on how an ODE should enter gently without a step function? My model is a similar case but using with PDE on comsol 4. The cases in Fig. Posted 2015/03/04 3:55 GMT-8 Heat Transfer & Phase Change, Heat Transfer & Phase Change Version 4. Frequency Study for Soft Iron Materials. 4 Last time step is not converged. Singular matrix. 0 Replies Last Post 16 okt. COMSOL 中经常出现的 Last time step is not converged. Feature:  Nonsymmetric matrix found. I am solving a transient model and changed the stepsize in the Times: field in the Study Settings, but the solver is still taking exactly the same timesteps. Thanks. Step Time Stepsize Res Jac Sol Order Tfail NLfail 0 0 out 1 2 0 0. The time-dependent study is run for 0. - Feature: The boundary load is a time varying load that follows a parabolic trend. Jul 30, 2013 · I am trying to model the voltage in function of time across a 3D multiturn coil inside of an electrical circuit. Apr 01, 2016 · The state of the system at any (n+1)th instant was not only related to the state of the system and input value at the previous time, but also to the input value at the present instant, n. All the subdomain settings and boundary conditions seem to be fine. Apr 06, 2016 · I actually don't mind that the time-steps take longer but the real issue is that the size of the time-steps are extremely small. At the frontal nose of the liquid thread, these forces act in an Aug 10, 2006 · 6) Repeat from 1) (next time step) using as a starting point for each particle, the channel in which it was at the end of the last time step until the desired simulation time is reached. Comsol time stepping Last time step is not converged. After each segregated solver iteration, the log reports the Pseudo time-stepping CFL-ratio defined as min (log (CFL)/ log (CFL ∞), 1. com/shared/images/logos/comsol_logo. 5 0 Replies May 24, 2014 · Time : 7. Browse the threads and share your ideas with the COMSOL community. Posted May 27, 2011, 12:43 PM PDT Version 4. Use of work plan FEAP User's Manual - Free ebook download as PDF File (. Discussion Closed This discussion was created more than 6 months ago and has been closed. Electroosmosis. Last time step not converged". The initial of mu is not zero, it is the density of the material Air, and PE. This process of mesh refinement is a key step in validating any finite element model and gaining confidence in the software, the model, and the results. Warning: zero AIR conductivity will cause bizarre numerical errors in the field system without any warning. evol,TIME)*rhof*test(p) As fig3. , 00:49 GMT-8 Fluid, Computational Fluid Dynamics (CFD), Heat Transfer & Phase Change Version 5. The value does not directly represent the internal solver time step, but it allows the user to identify what elements are problematic and control the time step. COMSOL 4. " but I found the other way to solve, I reduced the computing time in my model, change the time in STUDY 1 > STEP 1 > TIMES > range , for example, range (0 Make sure you change the time step actually. Time-dependent solver/BDF Number of degrees of freedom solved for: 142787 Nonsymmetric matrix found. 00983986), (0. doc; 国开2439电工电子技术-0007-期末机考复习资料. Posted 2 дек. The CFL ratio concerns the overall progress of the segregated solver and not individual groups. I then put back in a step and tried running it again. 算出来的结构的误差估计,比预设的收敛值要大,所以当前的结果仅供参考,数值精度不够。 修改的话,首选加密网格。 罗兰数字音乐教育. Two physics (transport physics and solid mechanics physics) are included in model to simulate a porous media in solution environment. Posted 26. 3e-9. × Warning Your internet explorer is in compatibility mode and may not be displaying the website correctly. 3. Sometimes even you feel you make changes, COMSOL still runs based on previous setting. Last time step is not So I set the time step as 0:1e-5:3. KNOWLEDGE BASE Error: Failed to compute elastoplastic strain variables; BLOG Plotting the Algebraic Residual to Study Model Convergence; KNOWLEDGE BASE Improving convergence in nonlinear time dependent models; FORUM Solution does not converge Last time step is not converged. 004418200072338524: Nonlinear solver did not converge. - Feature: Apr 03, 2011 · Note: This discussion is about an older version of the COMSOL Multiphysics Last time step is not converged. Since the exact time history of the load is not known, it is difficult to perform a time-dependent analysis. 0285229), (0. 167138,0. Out of memory during LU factorization. 153238,0. 2016 г. Get expert help with questions and issues related to COMSOL Multiphysics software. The coupling of two consecutive time-steps is realised by an implicit backward differentiation formula (BDE) scheme of the first order as used in . However, i replaced the E with the modulus, and the bottom portion with a mesh size of 1, and I ran the analysis. In my project, I am using "magnetic field" and "electrical circuit" physics, with "coil geometry analysis" and "time-dependent" study. I am making use of the example model in comsol library (positive column-2d). Not sure which modulus you are using? I used structure mechanics modulus, and my problem was because the boundary condition was not properbly set, it's under-constrained. zimmerman_wbj 2008-04-30 14:29:19 UTC. Exercise 1: Intro to COMSOL (revised) Transport in Biological Systems Fall 2015 Overview In this course, we will consider transport phenomena in biological systems. The trial ran for Assembly time for surface-to-surface radiation models is now reduced when COMSOL Multiphysics has access to multiple cores. I solved the model, and everytime I got was: Error: Time 1. cn 地址:上海市杨浦区平凉路1500号2号楼5楼 Free essays, homework help, flashcards, research papers, book reports, term papers, history, science, politics 13 Jan 2015 Last time step is not converged. 299997707294361e-006 Last time step is not converged. The relationship between mesh size and time step length is known as the CFL number: CFL = c*Δt/h, where Δt is the time step and h is the mesh size. Tissue temperature did not reach more than 111ºC in any of the simulations and the temperature in the electrode was always Apr 19, 2012 · Note: This discussion is about an older version of the COMSOL Multiphysics ® software. wtc (turn off smoothing and refinement). The time dependent solver is computing the solution to  Last time step is not converged. A real-time simulation is achievable if the computation time for a time step is less than the time step duration . At a given CA time step ( ), the states of the cells is simultaneously modified following a global transition rule which involves the states of the cells in the neighborhood of each cell of the grid (Von Neumann & Burks, 1966). - Feature: Time-Dependent Solver 1 (sol 1/t1) I looked into previous posts on the convergence problems, tried to refine the mesh, break down time intervals in the time-dependent analysis, but cannot solve this problem. nl www. I'm using incompressible Navier-Stokes and I have tried a steady- and transient state system. ' Besides, when I try to add a turbulent bubbly flow (two phases flow), even under stationary condition, there is a problem about 'the matrix has zero on diagonal'. After a review about solution strategies for Assemble finite element matrices for the first and last time steps of a transient structural problem. 5 are not affected, unless reloaded from the material library. " but I found the other way to solve, I reduced the computing time in my model, change the time in STUDY 1 > STEP 1 > TIMES > range , for example, range (0 Jul 28, 2014 · The first argument is a positive real number for the actual time. How to fix such problem? Thank you! 1 Reply Time 0: Failed to find consistent initial values. That has already saved me hours to days of time, because looking at the residual is much better than guessing; without this I would be following a false trail. 15s (which is just as the step completes) the time step size shot down to the 10e-13 range then after a further 10 minutes or so of slowly falling it got stuck oscillating between 6. PNG 2. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help. 2 (Heat Transfer and Particle Tracing Modules). 4 ). If you are not solving a wave-like problem, and if the non-convergence is happening when a Sep 29, 2008 · Last time step is not converged. at coordinates: (0. Best regards, Li May 15, 2018 · In our example, the time steps are on average five times larger in the phase field method, which results in a five-times-larger computation time for the level set method. -Specification of Initial values of variables solved for is now available also on the study step level and not only in the solver sequence. In general, at lower currents, Re has the ability to heat faster than Ta due to higher electrical resistivity at low temperature ( Fig. To demonstrate backtracking, let’s run the auxiliary sweep with 1000 and 1 as the values for “visc_ramp”. I am not able to infer from this graph whether my solution has converged or not. Browse our knowledge base now. 2 empowers current users to do more with their simulation environments, while new industries will now be able to leverage the innovation of multiphysics simulation. If you are modeling a problem with wave-like solutions, first make sure to apply the settings described in Knowledge Base 1118: Resolving time-dependent waves and also review Knowledge Base 1244: Solving Wave-Type Problems with Step Changes in the Loads. It Note: This discussion is about an older version of the COMSOL Multiphysics Last time step is not converged. Maximum number of iterations reached. 4 " tutorial to simulate my model. 但是改用稳态求解器就没有问题。 于是我给体系添加了一个体积力(重力),图2,不管是稳态还是瞬态都是计算出错,求大侠帮忙解答。让这个模型可运行,本人感激不尽。 稳态出错提示: Failed to find a solution. 0 under the Advance tab of the Mesh Parameters window. Best regard, QG XIAO 2011-02-26 xiaoqg2003 å `ä»¶äººïŒ Hamidrè za å `é æ ¶é ŽïŒ 2011-02-26 06:17:49 æ"¶ä»¶äººïŒ COMSOL_Users æ é ïŒ Jan 01, 2018 · The height Δh of the thin layer of material deposited at each time step into the LSFF domain, as shown in Fig. View all of the study and solver updates here. 2 represents a significant expansion of the software’s applications, features, and functionality. initial solution, the time loop is launched and repeated until the last time-step has been calculated. Time: [max time solved for] Last time step is not converged. (2008) recently have published a contribution about nonlinear soil-structure interaction using an iterative coupling technique. Controlling the Time Dependent solver timesteps Solution Number: 1254 Versions: All versions. Sep 26, 2011 · Anyway. It If you are modeling a problem with wave-like solutions, first make sure to apply the settings described in Knowledge Base 1118: Resolving time-dependent waves and also review Knowledge Base 1244: Solving Wave-Type Problems with Step Changes in the Loads. pdf), Text File (. FEAP User's Manual - Free ebook download as PDF File (. In practice, with the If you are solving a stationary nonparametric problem, the last converged Newton iteration is stored in the recovery file; selecting Continue causes the software to resume solving from this stored state. COMSOL. "I would like you to verify our model and help us if any errors made in the modeling. The B-H curve is usually nonlinear, and it can be used in the stationary and time-dependent studies. Two physics (bioheat physics and moving mesh physics) are included in model to simulate a laser ablation over a part of the bone. 1, Version 4. I thus wonder if the Moving Mesh application mode in general is able to deal with non-Newtonian flow? Has anyone tried something similar? Kind regards, Andy--ETH Zurich Andy since I started working with comsol I have bening having the same problem and I thought it was because of the ram of my computer, but now I have changed It and still have it. html) in comsol, minimum is geometry, mesh units I think ( a full report is the best thing). The last time step returned from the time-dependent solver is not to be trusted. In a nutshell, Fluent calculates several various time scales and chooses the smallest one as the pseudo-time step. I used about 6 years STAR-CCM+ in automotive company. I thus wonder if the Moving Mesh application mode in general is able to deal with non-Newtonian flow? Has anyone tried something similar? Kind regards, Andy--ETH Zurich Andy I am using the level-set method. Radiation support for shell and solid interface coupling It is now possible to couple a domain interface and a shell interface that share the same temperature and radiosity fields (for example, the Heat Transfer in Solids COMSOL Multiphysics® version 5. While solving I had a probe ploting solutions and time step was right but when the study finished time step changed. Basic parameters are that, the heat flux will take place in walls through inner air, atmospheric air and water in pipes as in the model. Note that while COMSOL employees may participate in the discussion forum, Last time step is not converged. " Running the model without the step function works. COMSOL takes the step as specified by the user in the parametric sweep section and if cannot converge, takes smaller steps to go as far as possible. -The options First and Last are available as options for the solution numbers to select. 不懂啊。。。。。。。。。。第一次用 comsol 折腾好久了 Last time step is not converged. Generally speaking, biological systems of interest have interesting geometries and we are interested in things happening in time and space. Make sigma small but finite! I apply a step voltage pulse at 4us to terminal May 27, 2011 · Undefined value found for fluid transport with heat transfer . Apr 03, 2017 · Last year I have written a program loosly based on cfx4toFoam that can read a comsol 4. Not only will the numbers be crunched with less engineering effort, the analyses will be more accurate, thus supporting the whole product chain from conception to production. Running COMSOL Simulation (Next Layers Loop) for pixel #21 for curing time of 2 seconds for count# 3. Posted 02-Dec-2020, 12:49 am GMT-8 Fluid, Computational Fluid Dynamics (CFD), Heat Transfer & Phase Change Version 5. If a solution has already been computed for the specified value of time, COMSOL Multiphysics uses the computed solution. When encountered during time-dependent solution: the linear system matrix (which is a linear combination of the mass-, stiffness-, and possibly, damping-matrices) is singular. The tutorial presents a step-by-step guide for deriving the continuous constrained optimization problem forming the foundation of the Topology Optimization method, using a cylin-drical metalens design problem as an example. Posted 04. Actually, I am following the " models. Thank you. Create a transient structural model for solving a solid (3-D) problem. 173205,0), (0. 4 0 Replies Haoliang Lu are you sure your ODE enters gently the game, and do not pop in with a step function, giving issues for the solver to get to converge. Please suggest a solution. " I am new to comsol. It Convergence problems after mesh refinement. 01, absolute tolerance as 1e-15. So, for free surface problems at a small scale and for laminar flows where surface tension has a large impact (for example, in microfluidics), the phase field method is in Last time step is not converged. Apr 30, 2015 · By default, the last step in a geometry sequence is to finalize by forming a union, uniting all of the geometrical objects and meshing them as a single object. com/forum/ Last time step is not converged. However, since the computers used for classes typically do not have extra memory loaded, it is prudent to keep the problem size small. We will first considered the propagation of an initial pulse over a distance of 100 m in a three-dimensional geometry in a frequency band up to 600 Hz. Thanks, If you are modeling a problem with wave-like solutions, first make sure to apply the settings described in Knowledge Base 1118: Resolving time-dependent waves and also review Knowledge Base 1244: Solving Wave-Type Problems with Step Changes in the Loads. The past and present of mathematical modeling and FEA software is a success story. Last time step is not converged. Returned solution is not converged Nov 17, 2020 · Dear All, I am Using COMSOL for simulating my transformer model. 周一至周日 8:00-18:00 官网:www. Time 0: Failed to find consistent initial values. 1 9 Replies . 08. 022 Last time step is There are 19 degrees of freedom that do not occur in any equation (empty columns in matrix) for the variable r_lm. BLOG Buckling, When Structures Suddenly Collapse; KNOWLEDGE BASE Matrix has zero on diagonal; KNOWLEDGE BASE Error: Failed to find a solution. PNG: Ordinarily, for this problem we would not need to worry about this. 0193838), (0. converge result in comsol. To illustrate this issue and its resolutions, consider a simple fluid flow model as diagrammed below. 30 GMT-7 Fluid, Computational Fluid Dynamics (CFD), Studies & Solvers Version 5. 025 s as time step but comsol plots every 0. You may try deleting all the solvers and rerun again. Returned solution is not converged. The model is in attachment. You can make changes to these default settings in The Preferences Dialog Box in the Files section. 2,206 views2. last time step is not converged. txt) or read book online for free. FORUM Failed to find a solution. The next-generation software will be a significant step. I have written 0. 2K views. Study In Comsol Nov 13, 2008 · Sometimes it helps, but don't know how this is accomplished in COMSOL. 1 s. 0), where CFL ∞ = 10 4 is the steady-state CFL number. . 4 indicating "Failed to find consistent initial values". The thgn is tha y can solve a problem with a certain mesh, but If refine it I get the next message. 2 s and 477. Error: Failed to find consistent initial values. acdc. Solution. Oct 17, 2011 · are you sure your ODE enters gently the game, and do not pop in with a step function, giving issues for the solver to get to converge. 3a, but fails for 4. 2019 10:11 GMT−4. 3a 0 Replies . Dec 02, 2008 · I am currently just running a normal 3D incompressible flow problem in COMSOL 3, Last time step is not converged. In Spatial mesh displacement: Segregated iteration leads to undefined function value. 2a 5 Replies You need to disable deformed geometry and moving mesh nodes into stationary solver step as this need time dependent solver or frozen rotor solver. The load is a maximum of three times the body weight. - Feature: Time-Dependent Solver 1 (sol1/t1) 1. 1, Version 5. mar. It can read 3D and 2D and axial meshes. Time-dependent solver/BDF Number of degrees of freedom solved for: 142787 Nonsymmetric matrix found. Although the overall computational cost is considerable, the numerical results agree well with associated experimental data. So any help would be appreciated. 5, can be calculated using the following mass conservation equation : (22. 000blah blah blah. - Feature: Time-Dependent Solver 1 (sol1/t1) Discussion Closed This discussion was created more than 6 months ago and has been closed. 0164738, No Iterations 1 I am modelling a DC discharge in between 2 electrodes which are positioned asymmetrically. Step Time Stepsize Res Jac Sol Order Tfail NLfail 0 0 out 1 2 0 0 Error: Failed to find consistent initial values. 3a introduces a new model reduction feature, better flexibility when combining solutions, and more. However, if the Comsol Mutiphysics is used with a floating network license it is possible to use the client-server operation mode to access the remote calculation resources to solve large models, while continuing to use the graphics card in a machine The electrostatic equations are not to be taken literally as ”statics”, but as the observation or time scale at which the applied excitation changes are in comparison to the charge relaxation time, and that the electromagnetic wavelength and skin depth are very large compared to the size of the domain of interest [35]. The COMSOL recommended first step is to use the “model wizard” option to specify the nature of the multi-physics problem that you wish to simulate, such as whether the problem is 2-D or 3-D in nature, what physics will be included, and whether the problem is steady-state or time-dependent. 2020 г. They have been a tradition for Apr 01, 2016 · The state of the system at any (n+1)th instant was not only related to the state of the system and input value at the previous time, but also to the input value at the present instant, n. structuralmodel = createpde( 'structural' , 'transient-solid' ); Jun 01, 2019 · For the latter, the electrical power evaluated at the last time step for each current is 270. Jun 16, 2017 · This model will not converge with default settings. 2 Release Highlights COMSOL Multiphysics 4. 05 s from the convergence tests. Both models are attached in this message. 1 BICCG: Solving for Ux, Initial residual = 1, Final residual = 0. 2015, 02:54 GMT-7 Version 4. Posted 2019/11/13 5:21 GMT-8 Fluid, Microfluidics, Particle Tracing Version 5. -d(solid. Comsol time stepping COMSOL 问题 仿真模拟 COMSOL Multiphysics & HYPERWORKS 小木虫 论坛 Last time step is not converged. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for  13 Sep 2012 You can for instance get error messages such as "No convergence, even when using the previous solution when solving, until you reach the solution to your Reducing the time step is a good strategy when convergence  COMSOL reduces the time step size when it does not converge in the time or spatial domain, or even I believe, if it converges Last time step is not converged . with COMSOL Multiphysics version 5. 0, Version 5. COMSOL问题集锦_信息与通信_工程科技_专业资料。常用的comsol问题集锦 1. " I am using a fully coupled (advanced, direct) solver for now, as I haven't been able to get a segregated solver to converge for even the first time step. 0372259), Last time step is not converged. If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base. I have some particles also in the pipe but I think that those aren't any problem, if enyone has any tips I would be very happy. Jul 13, 2009 · Then click on "Get Initial Value", then COMSOL does exactly what I want, namely it plots as the initial value exactly the same solution as it has converged to last time. port 的本质仍是一种散射边界。 0. The method performs a very fast DLF using zooming algorithm associated with a fast-decoupled reactive power compensation (ZAFDRC) technique, not in all of the buses of the grid, causes to reduce the solution time, which is the most important issue in the real-time studies. It Last time step is not converged. 7a and b represent the transition from stratified flow to Taylor flow, in which the interfacial surface tension forces are represented by uniformly scaled vectors. 5 0 Replies Last time step is not converged. Version 4. 2. But! I changed my job recently. how can i COMSOL assertion failure. parametric sweeping with time-dependent and eigenvalue and parametric solutions as input. In the electrical circuit there is a voltage source generating a pulse . 3 0 Replies Mingzhe Cui Last time step is not converged. Consequently, the transverse normal stress in 0Z direction, which is calculated as Zcom = E [(1 ) Zcom + Xcom ] (1 + )(1 2 ) (2. I don't know how to solve these problems and I will feel very thankful if I can get some advises. This manual describes many of the features of the general purpose Finite Element Analysis Program (FEAP) to solve such problems. Stop when the total simulation time has been reached and compile information of the location of the particles remaining in the network and location and time of Mar 04, 2011 · As of Comsol 5. , ) and initialized the temperatures from the previous time step. Or you write your analytical expression directly in property value as suction of temeprature ans shear rate T*spf. I know how to do it, but what I don't know is how to make COMSOL use the previously result as initial step to the next one. I am attaching a picture of the same. Earlier time steps are within the specified tolerances. SO many step sizes are tried by COMSOL. Solve  28 Jun 2018 Failed to find consistent initial values last time step is not converged. 4 0 Replies Haoliang Lu Mar 19, 2019 · It's not about the handset; this is fixed wireless access using 5G. 4, the initial stress is modified as 400[kPa]. - ANSYS has an option where if a contact condition's status changes dramatically between two intermediate load steps, it can automatically split the load step in half to try and enhance convergence. Posted 30 нояб. 16046,0. Parameters setting: Showed in Fig. e coupling of two consecutive time-steps is realised by an implicit backward di erentiation formula (BDE) scheme of the rst order as used in [ ]. May 03, 2013 · These results were obtained at the last time-step prior to the detachment of the Taylor bubble. - Feature: Your Discussion has gone 30 days without a reply. 01 and another function that increase smoothly Any suggestion? Thanks For this reason, I would like to use an expression like: max(U_chns) from the last time step as gamma subdomain quantity. i look at Knowledge Base on comsol web site but i don't see any suggestion to avoid this. 5e-9 and 1. " ===== I have moved the toy electrostatics ES example (circular plate capacitor) over to EC. 2017 18. It demonstrates the effect and necessity of applying a number Sep 01, 2015 · The size of the time step is determined according to the material properties, mesh size and natural frequencies. It Hello comsol community, Last time step is not converged. Despite mid-60s degree temperatures, it’s beginning to look a lot like Christmas in Davidson (pictured are the Giving Trees on the Village Green). The print out looks like the following for a time step: Time = 0. " Jun 07, 2010 · Time 0. " I am really struggling with the basics of COMSOL. " "Feature: Time-Dependent Solver 1 (sol1/t1) Failed to find consistent initial values. Posted 30 mai 2015 à 15:10 UTC−4 Fluid, Heat Transfer & Phase Change Version 4. Jun 26, 2009 · Last time step is not converged. 4 W at 120 s, 421 W at 108. I'm trying to use parametric sweep. Shows how to build a model step by step. Mar 29, 2016 · If the solver ever fails to find a solution for the next lower viscosity, then it will try an intermediate value between the last converged value and the next user-specified value — a process known as backtracking. 2 mm in the electrode–tissue interface and a step time of 0. 00015 or less. Computation succeeds for Comsol 4. The Mesh Refinement Process A good finite element analyst starts with both an understanding of the physics of the system that is to be analyzed and a complete description of the geometry of the an approach offers a great reduction in time step, but the numerical effort required for differentiation leads to similar computation performance. " Last time step is not converged. sr^-. temperature rise and exposure time. Universe of Physics Mean Time is an Note that materials added to a model prior to COMSOL Multiphysics® version 5. ppt; 民用建筑节能设计审查备案登记表及详细要求. The reason for this extra time taken is the extra effort by COMSOL which involves : 1. Failed to evaluate variable. Electromagnetic waves scattering off of a nano sphere. - Feature: Time-Dependent Solver 1 (sol1/t1) I've looked at as many tutorials / discussion forums as I can find that look even vaguely related but can't find anything helpful. How to fix such problem? Thank you! 1 Reply When I try to solve the problem by Comsol time- Nonlinear solver did not converge. Typically, I need to enable Strict or Intermediate time stepping and then introduce sometimes 10, but sometimes up to 200 evenly-spaced time steps over the duration of the step-up (which is smoothed, so looks like a sigmoid). Based on the initial solution, the time loop is launched and repeated until the last time-step has been calculated. Background. gif https://www. This tutorial is the first on a series of 3. 3b and 4. This also speeds up the overall solution time. 8 W at 51. 15s but the time step I'm getting is around 0. 45) Δ h = m ˙ Δ t A j e t m e l t ρ p where Δt (s) is the time step, m ˙ (kg/s) is the powder feed rate, and p p (kg/m 3) is the powder density. The specific value of the step may be accessed using the CURRENT_TIMESTEP macro in a UDF. Jun 07, 2010 · Time 0. rdec. Now I have read what might cause this, suggestions include my mesh type, I have varied this but without success. Jul 14, 2016 · The way how the pseudo-timestep is defined can be found in Fluent Theory Guide, see the chapter "Automatic Pseudo Transient Time Step". Nov 12, 2020 · Failed to find a solution for all parameters, even when using the minimum parameter step. The calculated initial void ration e0 is 0. Out_of_memory_in_Jacobian_computation Last time step is not converged. Nonlinear solver did not converge. If you are not solving a wave-like problem, and if the non-convergence is happening when a Last time step is not converged. 05 seconds. 022 Last time step is mization during the last three decades. Engineering structures are normally built with stiff materials, limiting the time step to an extremely small size. I Apr 03, 2011 · Note: This discussion is about an older version of the COMSOL Multiphysics Last time step is not converged. sh. I don't find a way to solve this problem, if you succeed can you say me how you did please? There is only one ^ in your expression, try "mu+eps" to see whether it works or not. I Sep 29, 2008 · Last time step is not converged. Posted 31 gen 2018, 14:54 GMT-8 Fluid, Heat Transfer & Phase Change Version 5. As fig5 showing: The above settings are to make sure the state of stress in the yield surface. comsol. Results We obtained a value of X = Z = 40 mm, a grid size of 0. There are two studies performed, a time-dependent and a stationary one which included a load buckling step. The other was sharp corners, my geometry has sharp corners, and suggestions have been to fillet the corners, however, I can't figure out how to fillet 3D corners. What changes can I make to the solver settings to fix this? Solution. For example, if 1 is used in the first argument, it means t = 1 (in the relevant unit of time) and not the lowest time the problem is solved for. It is implemented by passing the required Last time step is not converged. Ansys Parameter Sweep The method performs a very fast DLF using zooming algorithm associated with a fast-decoupled reactive power compensation (ZAFDRC) technique, not in all of the buses of the grid, causes to reduce the solution time, which is the most important issue in the real-time studies. showing. 3e- 4, relative tolerance as 0. To do this we use a new feature of 3. So I set the time step as 0:1e-5:3. A similar problem is already solved in the Level Set application: Variable hmax_chns is defined in every subdomain as the maximum of h element size in the specific subdomain. 请问各位大虾,error和warning显示的内容是什么意思呢 Mar 26, 2017 · Time Dependent of intake manifold. 2, one can now plot residual(u), provided they enable storing the residual in output under "Advanced" solver settings. However, it is not the case with Zcom calculated by the low-order interpolation function, see (2. WELCOME TO THE COMSOL CONFERENCE 2017 using it over the last year. 2a 3 Replies Pradeep Last time step is not converged. 145496,0. " Posted 18. Any idea why this is happening. This time it did something similar to Amir's after nearly 0. I will also discuss what solvers, time-step selection, parametric May 28, 2020 · The cell wave time scale can be visualized by plotting the variable elte. Ansys Parameter Sweep IBWAP2008 - Scribd IBWAP2008 Study In Comsol Last time step is not converged. and it gets even smaller as the fluid flow magnitude increases. It works fine when I try for time steps <20 (secs). Switching back to Newtonian flow, the transient solver starts (though results are wrong). ecore_transformer5. The development of this work has allowed us to obtain useful indications for designing a Continuous Air May 01, 2014 · At the end of each time step (Δt, s), the temperature field in the food domain was saved along with their coordinates. 6384e-008: (the value was keeping changing but it always stucked in some value of power 1e-8) Nonlinear solver did not converge. , 00:45 GMT-8 Heat Transfer & Phase Change, Geometry, Mesh, Modeling Tools, Parameters, Variables, & Functions, Studies & Solvers Version 5. Shahid Ahmed April 12, 2016. " during Time dependent solver. Warning: SOR line did not find any lines. Now I have to simulate some physics related semiconductor The COMSOL discussion forum covers a wide variety of simulation topics. Im using plasma module and a time depende study. Hope this would be help. Jul 10, 2007 · I have had the same problem as mentioned above, with many pressure itterations, but have had higher sum local and global values (about e-4). 2a mphtxt or mphbin file and convert it into an Openfoam mesh. I hope this will help the model to converge. 44. The pore water pressure is coupled into the model with this step. Oct 28, 2018 · Hello. My model is also 2-d. 3 0 Replies Afonso Dias Last time step is not converged. I got this problem before. The information provided may be out of date. 22. 4, Version 5. COMSOL Moderator. I can then go to Solver Manger and click "use stored solution as initial value", but it still doesn't converge. time-dependent extension of a stationary problem. A Cellular Automata (CA) is a mathematical concept that permits the generation of discrete time‐evolving cells grids. The big advantege of comsol is that it is easy to add new yield ctiteria if it can have converged results. https://www. If you are not solving a wave-like problem, and if the non-convergence is happening when a with transient analysis when model is perfect and all the BCs are correct this error can be resolved by changing solver configuration. However, it cannot be used directly in frequency-domain studies. 公司治理分析解析案例例子-从方太看公司治理. A detail report on sample coding problems in Finite element method 现在就从 comsol 博客获取灵感。 了解如何借助多物理场模拟和仿真来变革和优化工程设计。 × Warning Your internet explorer is in compatibility mode and may not be displaying the website correctly. To start a new discussion with a link back to this one, click here. I initialize the level-set function as it is recommended in the user guide and use that initial value for the transient solution. Any longer time steps will not make optimal use of the mesh, and any shorter time steps will lead to longer solution times with no considerable improvements to the results. Don't know if COMSOL has this option. -Feature: Time--Dependent Solver 1 (sol1/t1). Matrix is singular When encountered during time-dependent solution: the linear system matrix (which is a linear combination of the mass-, stiffness-, and possibly, damping Comsol time stepping. 10. 20). 2. nl Denmark COMSOL A/S Diplomvej 376 2800 Kgs. Benelux COMSOL BV Röntgenlaan 19 2719 DX Zoetermeer The Netherlands Phone: +31 (0) 79 363 4230 Fax: +31 (0) 79 361 4212 info@comsol. Posted 03-Mar-2011, 5:06 PM GMT-8 AC/DC & Electromagnetics, Studies & Solvers Version 5. 6556. Hi if you do time transient solving in "automatic time steps" the COMSOL sover is set up for diffusion type solvers, so it expects to be able to take larger and larger steps, ut if you introduce periodic BC conditions, the solver might step over a transition. I am using the level-set method. And of course I tried to solve the problem, by changing the absolute tolerance, since COMSOL  Hallo sir, hi have a question. The random number is multiplied with 0. To get the boundary names you need to make a reportfile (. 2 W at 120 s, 348. In the actual boundary conditions of the pair, I copied and pasted the same expression as your model. The issue I am facing is that my convergence plot is a semi-log plot showing reciprocal of time-step v/s time step, even though I have fixed the time step. when i simulate i have forever this Picture. Jahromi et al. Given the time series of the input (a triangular impulse) and of the output functions, thermal response factors were computed using state equation. It seems the timesteps that the solver is taking are not Chapter 2 Convergence of Numerical Methods In the last chapter we derived the forward Euler method from a Taylor series expansion of un+1 and we utilized the method on some simple example problems without any supporting analysis. Nov 15, 2016 · Segregated Step 1 System matrix is zero. Next, COMSOL Multiphysics ® software called the MATLAB routine to rotate the food to the next discrete angle (dθ) (Eqs. I keep getting the same error: " Failed to find consistent initial values. Time: 0. 21) is not equal to the analytical solution along the thickness when bending occurs. 2011, 04:22 GMT-7 AC/DC & Electromagnetics, Heat Transfer & Phase Change, Materials, Results & Visualization, Studies & Solvers 0 Replies Juraj Kapusta Mar 18, 2011 · Last time step is not converged. To do this I use the Magnetic Fields and the Electrical Circuit physics and a Time Dependent Study with a coil current calculation preceding it. error is: Failed to find consistent initial values. • Jun 28, 2018. 1. Hi Walter, I ran a simulation implementing Thermostat with Events Interface, it works well with Up and Down Temperature Conditions, however wonder how to link implicitly the heating end-time to the cooling start time if a soaking time of say 200 s is needed between heating end-time and cooling start-time. 2, Version 5. 1 3 Replies Convergence problems after mesh refinement. comsol last time step is not converged

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