It can be used for a variety of different purposes, examples of which are presented here. From such source-destination pairs, one can infer the general mapping from superposition. Now suppose we would like to evaluate the temperature at one point of the rotating wafer. They are not necessarily pertaining to the x or y coordinates in the source or destination. Using source and destination maps to define implicit relations between source and destination coordinates in a General Extrusion operator. All selected faces must lie in the same plane. Then we add three distributions, one corresponding to each of the mapped mesh distributions. Mapping of data between different components in the model to perform submodeling, Mapping between components to extract results on different geometries. Hi If excavating close to a retaining wall, youre subjecting it to additional forces it was not originally designed for, and it may require subsequent support. Extrusion operators are used to identify which point in the source entity corresponds to a point in the destination entity. Box 3488 Youngstown, OH 44513. "Using the General Extrusion coupling operator in COMSOL: Dynamic probe http://t.co/q6jAnnc5HC" To start a new discussion with a link back to this one, click here. Ivar. 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. Alle Rechte vorbehalten. 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. 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. Take a look at the figure below. You can fix this by pressing 'F12' on your keyboard, Selecting 'Document Mode' and choosing 'standards' (or the latest version Mapping of data defined on a cross section (left) around an axis of symmetry and into a volume (right). With a voltage terminal at the bottom of the device and ground at the top of the device, the following results are obtained. This worked perfectly for a point moving on a surface. 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?. 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. The General Extrusion operator will map data from the boundary into the volume, along the z direction, as shown in the following screenshots. Extrusion operators are used to construct pointwise relations between source and destination points. Enter in the equation shown which is the ramp function of the wall deflection, with an added term limiting the expression to occur only when the depth is below the strut. Thanks in advance. Previously on the blog, we introduced you to Linear Extrusion operators and demonstrated their use in mapping variables between a source and a destination. Within the original domain, a displacement of zero is used. Now that the velocity field is defined throughout the modeling domain, the species concentration at the inlet is defined via the Inflow boundary condition. To add a General Extrusion operator, we go to Definitions > Component Couplings > General Extrusion. Sample data defined on the xy-plane, centered at the origin. From the Extrude from list, select Faces to extrude planar faces from the 3D geometry. Editing and Repairing Imported Meshes in COMSOL Multiphysics, Exploiting Hardware Parallelism with COMSOL Batch Sweeps, The Graphics Window: Effective and Beautiful Postprocessing, Thank you so much for this article, I was in need of something that shows the mathematical operations of the extrusion coupling. In an upcoming blog post, we will walk you through how to use the operator to map cross-sectional data from one or several cross sections onto another cross section for geometries where the cross section dimensions do not change over the length of interest. With the General Extrusion operator defined, we can now use it throughout the model. Using a General Extrusion operator to copy data from the 2D axisymmetric domain to the corresponding 3D domain. Now that the velocity field is defined throughout the modeling domain, the species concentration at the inlet is defined via the Inflow boundary condition. A retaining wall is used to hold back soil from a region you dont want it to move to, such as a lower level of the ground. Why are all the domains selected? Settings used to revolve data about the azimuthal axis of a cylindrical coordinate system. 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. There are some models. The General Extrusion operator will map data from the boundary into the volume, along the z direction, as shown in the following screenshots. Left: Temperature varies linearly from left to right. The Periodic Flow condition is used to set the velocity so it is identical at the inlet and outlet boundaries, allowing us to specify a pressure drop over a single unit cell. The materials have already been created and set up for this model. The following types of Extrusion Coupling Operators are available: Several cases are illustrated in the table below. This applies a varying species concentration over the inlet boundary. General Extrusions makes simple and intricate aluminum shapes through both long and short production runs. The results of the analysis, including the concentration and the mapped velocity field, are depicted below. I apologize of my explanation sounds vague or ambiguous. listed if standards is not an option). Add boundary 8 and change the y-axis data expression to v and use millimeters as the unit. This problem can be solved by using a General Extrusion coupling operator to dynamically map the solution at a particular point (moving or stationary) onto a fixed source. General Extrusions is engaged in fabrication, anodizing, and powder coating, as well as aluminum finishing and machining. General Extrusion, Linear Extrusion . General Extrusion Variable. 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. Given an expression defined on a plane, e.g., the xy-plane, it is desired to map this . Sample data defined on the xy-plane, centered at the origin. Ce consentement peut tre retir tout moment. There are two ways to model an excavation in COMSOL Multiphysics, both of which include a parametric sweep. FIGURE 1. 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). The effect of the rotation of the wafer is modeled through a transport term in the governing heat transfer equation: The transport term in this equation, \bf{u}, is used to account for the rotation of the wafer, so it is not necessary to explicitly rotate the geometry. How did you select the source in the general extrusion settings? Multiscale Modeling in High-Frequency Electromagnetics. Ivar. If the nonlocal couplings you want to simulate are not included in the built-in features of COMSOL Multiphysics, you can use the strategies youve learned today to implement them. A prescribed displacement is also needed for the wall_soil boundary created earlier. The company's manufacturing operations, which include a Youngstown, Ohio plant, comprise 220,000 square feet. Add a distribution for the wall diaphragm and enter 60 for the number of elements. Linear Extrusion operators are easier to build, but their utility is limited to affine transformations.General Extrusion operators are more general but take more work to define. http://www.comsol.com/model/laser-heating-of-a-silicon-wafer-13835, Multiscale Modeling in High-Frequency Electromagnetics. The General Extrusion operator is used to define the velocity field in all three periodic domains. Create a second line graph, showing the surface settlement, or vertical displacement, as a function of the distance from the wall. For affine relations, General Extrusion operators can be used as an alternative to Linear Extrusion operators. Right click again to duplicate it twice, since we want similar settings for the second and third struts. In the Work plane list, select the work plane to extrude from. For such a unit cell model, the walls of the channels are set to the Wall, No Slip condition. The player button feature allows you to see all the excavation depth results in one animation. In these first two examples, the Use source map check box in the Source section of the settings window has been left unchecked. An Outlet boundary condition is applied at the other end. The components of this velocity field are now defined in all of the repeated domains via the General Extrusion operator: genext1(u) and genext1(v), respectively. Check out our Deep Excavation Model for more information. As you can see, they are in the same location but are different boundaries. at an interface. General Extrusion - COMSOL Multiphysics Then the naming and differentiation between time and spatial variables is basically a convention issue, the math behind does not really change Name: genext1 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. Sample data defined on the xy-plane, centered at the origin. If you have already computed the solution to the finite element problem, then you can simply evaluate temperature at the destination points by clicking on the update solution option in the Study toolbar, or you can dynamically probe the variable genext1(T) evaluated at a point while you compute the solution to the finite element problem. The last step before computing the model is defining a range of depth parameters for the parametric sweep. This is exactly why COMSOL Multiphysics allows us to specify implicit relations between source and destination coordinates by using two mappings: the destination map and the source map. To evaluate the temperature at the destination coordinates, you can call the General Extrusion coupling operator with a temperature argument, as genext1(T), where T is the dependent variable name for Temperature. When it comes to general nonlinear mappings, General Extrusion operators are necessary. Thus, every point in the original domain is mapped along the positive x-direction by the specified displacement. To implement, define a General Extrusion operator on a boundary parallel to the xy-plane, with the z-expression blank for both the Source Map and a Destination Map. This approach is also useful in other analyses including structural contact or surface-to-surface radiation in heat transfer. To add a General Extrusion operator, we go to Definitions > Component Couplings > General Extrusion. First a mapped mesh for the retaining wall domain. Note: This discussion is about an older version of the COMSOLMultiphysics software. General Extrusions makes no exclusions with its extrusions. I have defined a general extrusion coupling operator to obtain the dependent variable (in my heat transfer case, the temperature "T") at a boundary. The flow solution on this unit cell is also plotted, as shown below. Enter the expression for the general extrusion operator from earlier. But finally COMSOL basics is a PDE solver tool for a given subset of useful functions, of the type used for common physics (that fits in the global or coefficient form. Settings used to revolve data about the azimuthal axis of a cylindrical coordinate system. Disp is defined as one of three different scalars (0,1.5,3 mm) as per the fourth figure. 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. 3 Replies, Please login with a confirmed email address before reporting spam. point 2 there simply involves time varying coordinates of the focal point of the laser beam in the example model : http://www.comsol.com/model/laser-heating-of-a-silicon-wafer-13835. 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. Submit feedback about this page or contact support here. listed if standards is not an option). In the 4.0a interface i do not know where to define the variable Va ( source) and its expression (V). CNC Machining for Aluminum Extrusions. Therefore, only a single operator is needed to map the velocity field into all of the domains. Now we will use the operators in the physics nodes to implement the boundary conditions. In this example, a 26-meter excavation is modeled by means of a parametric sweep, with a step size of 2 meters. Gaining Understanding of Complex Phenomena with Virtual Laboratories, The Graphics Window: Effective and Beautiful Postprocessing, How to Use Maximum Likelihood for Parameter Estimation in COMSOL, Thank you for your Blog. Nonlocal Couplings and Coupling Operators - COMSOL Multiphysics General Extrusions, Inc. | Aluminum Extrusion for Ohio It can be used for a variety of different purposes, examples of which are presented here. Take a look at the figure below. Right click the Boundary Load 3 node to rename it Strut_1. listed if standards is not an option). problem with general extrusion - comsol.de