Is it possible to "paste" two functions in COMSOL? Now we will create a 1D plot and a line graph, with the wall diaphragm as the selection. The Micromixer tutorial, available in our Application Gallery, is an example of such a model. Extruding Data Along a Direction. The variable Disp is individually defined within each of the three domains, as shown in the figure below. Stay tuned! Extrusion operators are used to identify which point in the source entity corresponds to a point in the destination entity. Take a look at the figure below. For example, if the intermediate mesh is in 2D space, there is no z-expression field. this defines if you should us a linear or general Extrusion or Projection This worked perfectly for a point moving on a surface. 3M dof and can be solved in 86s, when no gaps are present and we can rely on a conforming mesh). An example of defining such a rotation matrix is detailed in this previous blog post. It can be used for a variety of different purposes, examples of which are presented here. http://www.comsol.com/model/laser-heating-of-a-silicon-wafer-13835, Multiscale Modeling in High-Frequency Electromagnetics. Discussion Closed This discussion was created more than 6 months ago and has been closed. First, did you only the repeating unit in your graphics window before using the General Extrusion and Periodic Boundary conditions node or was it the entire geometry? A destination map and source map is specified here. Thus, every point in the original domain is mapped along the positive x-direction by the specified displacement. x_s = ax_d + by_d + e, \qquad y_s = cx_d + dy_d + f. r_s = \sqrt{x_d^2 + y_d^2}, \qquad z_s = z_d. Similar to the first two, for the third strut, add the third strut boundary and change stage 2 to stage 3. The Shockley diode equation for the current-voltage (I-V) relation is used at the junction. Several cases are illustrated in the table below. listed if standards is not an option). Please can you explain what I am doing wrong? Add a soil plasticity node and you can see that the yield criterion is DruckerPrager, but we still want to match it to the Mohr-Coulomb criterion. Note that while COMSOL employees may participate in the discussion forum, COMSOL software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team. Therefore, we have, Now we need to find the constants a,b,c,d,e, and f. Since source points (0, 0); (1.0, 0); and (0, 1.0) correspond respectively to destination points at (0, 0); (1.5, 0); and (0, 1.5), we get. An Outlet boundary condition is applied at the other end. Center: Temperature along the parabola. Then we add three distributions, one corresponding to each of the mapped mesh distributions. Can you help me out? Is it possible to do this within GUI, or do i have to do it via MATLAB? Now you know how to use the General Extrusion coupling operator to probe a solution at a moving point. The other option is to start with the already excavated geometry, and simulate the excavation using a boundary load. Hi, First a mapped mesh for the retaining wall domain. How to use the General Extrusion coupling operator to probe a solution at a moving point http://comsol.com/c/10mb Here is an interesting question: How can we easily probe the solution at a point that is moving in time, but associated with a stationary geometry?. Thank you for your time. General Extrusion Variable - comsol.it The settings of the General Extrusion coupling operator are shown below: Because the source and destination objects have different dimensions, affine transformations are impossible. Click plot to view the displacement at the different excavation depths. Schematic diagram of COMSOL coupling with external code RMC. The focus of this blog post is on the transformation T : x_d \rightarrow x_s.. COMSOL Multiphysics offers two coupling operators to specify this mapping: Linear Extrusion operators and General Extrusion operators. Lets consider a laser heating example where you have a moving heat source, the laser, and a moving geometry. Extrusion operators can be used to access the electric potential on the other side of a junction. listed if standards is not an option). Sample data defined on the xy-plane, centered at the origin. Example 1 In our earlier blog post on Linear Extrusion operators, we considered an affine mapping that pairs up points 1, 4, and 2 in the source domain to points 1, 5, and 3 in the destination domain. This computed flow field can then be used as input for the convection-diffusion equation governing the species concentration. Previously on the blog, we introduced you to Linear Extrusion operators and demonstrated their use in mapping variables between a source and a destination. Therefore, we can greatly reduce our model by solving only for the fluid flow within one unit cell and patterning this flow solution throughout the modeling domain for the convection-diffusion problem. The General Extrusion operator maps expressions defined on a source to an expression that can be evaluated on any destination geometry where the destination map expressions are valid. When using Linear Extrusion operators, we visually indicate the mappings for enough points (bases) and COMSOL Multiphysics figures out how to transform the remaining points. There are some models. We can simply enter the time varying coordinates in the x, y, and z-expressions of the destination map. It will always be requested to be evaluated at the destination coordinates entered in the settings of the General Extrusion coupling operator. #resolventtip: Get the best performance out your 'General Extrusion The number of destination map expressions is the same as the space dimension of the intermediate mesh. Although it is not strictly necessary to do so, the mesh is copied from the one domain used to solve for the fluid flow to all of the other domains. L=\frac{x_s}{2}\sqrt{1+4(\frac{x_s}{d})^2}+\frac{d}{4}\ln(2\frac{x_s}{d}+\sqrt{1+4(\frac{x_s}{d})^2}), we introduced you to Linear Extrusion operators, earlier blog post on Linear Extrusion operators, Using the General Extrusion Coupling Operator in COMSOL: Dynamic Probe, Using General Extrusion Operators to Model Rotation, Using General Extrusion Operators to Model Periodic Structures, Submodeling: How to Analyze Local Effects in Large Models, Postprocessing Local Data Using Component Coupling, Multiscale Modeling in High-Frequency Electromagnetics. A circular micro-electrode array with three phases is designed and prototyped using PolyMUMPs process for AC electro-osmotic flow pumping. Lets now explore how to use a General Extrusion operator to copy data from a 2D axisymmetric component to a 3D component, such that the source and destination points correspond to the same point in space. For clarity, we did not use this trick here. An initial stress is added to the model as well to simulate the in-situ stresses in the x, y, and z directions. It also provides design assistance and engineering support. We can similarly evaluate the temperature at any other point. En fournissant votre adresse email, vous acceptez de recevoir des emails de COMSOL AB et de ses filiales propos du Blog COMSOL, et acceptez que COMSOL traite vos informations conformment sa Politique de confidentialit. Disp is defined as one of three different scalars (0,1.5,3 mm) as per the fourth figure. Add depth as the continuation parameter, and click the range button. Within their design, a common goal is to achieve optimal mixing within a small surface area, hence the serpentine channel. I guess your problem is that there is no recalculation after defining genext1, and this error will not be prompted after the calculation. To apply what we have learned thus far, lets now build a diode model using the Electric Currents physics interface in COMSOL Multiphysics. Now we can add the boundary constraints, including a symmetry on the left, a fixed constraint for the bottom boundary, and a roller for the right boundaries. BLOG Using the General Extrusion Coupling Operator in COMSOL: Dynamic Probe BLOG Accessing Nonlocal Variables with Linear Extrusion Operators KNOWLEDGE BASE Understanding the Fully Coupled vs. Given an expression defined on a plane, e.g., the xy-plane, it is desired to map this data along the z direction. We have discussed how the General Extrusion component coupling can be used to set up a linear pattern of a periodic solution as part of a multiphysics analysis. Rename the third strut to finish off the physics set up. 50K views 6 years ago Creating Geometries in COMSOL Multiphysics: Tutorial Series COMSOL Multiphysics contains a handful of tools to quickly and easily convert 2D planar geometries into 3D. I hope I have not missed it. However, if we want to use variables from a 2D axisymmetric component in the physics node of a 3D component (i.e., thermal expansion), we need to utilize General Extrusion operators. In the Work plane list, select the work plane to extrude from. Why are all the domains selected? The same transforms can be implemented in three dimensions. We can choose a prescribed displacement to make sure the soil at boundary 4 only moves in the y direction. I deplore the glaring oversight of COMSOL: Considering how frequently one encounters problems that include a combination of Rotationally-Symmetric and Cartesian components, that COMSOL has not seen fit to provide a specific operator for this case! The applied heat load is described via a user-defined function, hf (x,y,t), that describes how the laser heat load moves back and forth along the x -axis in the global coordinate system. General Extrusions is owned and run by the Schuler family. Settings used to revolve data about the azimuthal axis of a cylindrical coordinate system. Add a distribution for the wall diaphragm and enter 60 for the number of elements. Then the naming and differentiation between time and spatial variables is . The General Extrusionoperator maps expressions defined on a source to an expression that can be evaluated on any destination geometry where the destination map expressions are valid. Instead, at every destination point, it first evaluates T_d(x_d,y_d) and carries out a mesh search operation to find the point on the source where this evaluation matches T_s(x_s,y_s). There are two ways to model an excavation in COMSOL Multiphysics, both of which include a parametric sweep. I have a 1D model (time dependent) and a 2D model (stationary). All selected faces must lie in the same plane. Second, I used the defined the Variable Disp three times as in the images above but with different values (with increments in the periodic direction specified) while the destination map setting had as input z-Disp as suggested above but I got the error Error in multiphysics compilation. Duplicate parameter/variable name. Simulation Organogenesis in COMSOL: Deforming and Interacting Domains We were the first North American aluminum extruder to achieve ISO 9002 Certification. We want a depth ranging from 0 to -26 meters with a step size of two meters. Variable: comp1.Disp. Extrusion Model Coupling Operator takes a local concentration as an argument at the following boundary and evaluates it at the corresponding point at the leading boundary. The General Extrusion operator will map data from the boundary into the volume, along the z direction, as shown in the following screenshots.