Comsol emw variables. 12 From the Eigenfrequency list, choose 2.

Comsol emw variables Havva Erdinç . 5. EMW interface solves for the wave equation. PDT Materials, Modeling Tools & Definitions, Parameters, Variables, If you require further help with this, please contact COMSOL's Support Team (support@comsol. The integral of the electric energy density over all domains is already computed via the built There are 1 degrees of freedom giving NaN/Inf in the vector for the variable mod1. S21)^2) and R0 (abs(emw. I have not changed anything in my study node especially to call the earlier simulated "emw. 87 COMSOL makes every reasonable effort to verify the information you view on this page. Ephi should be used. In the RF module, the three components of the Poynting vector are directly available in post processing, as (emw. In your case you can define: Qj = d(rho_E,t) This operator is described further under "The differentation operators" in the help documentation. nx and emw. The resonant frequencies obtained with If anyone has any experience with probing variables in COMSOL, or who can help me conduct this sweep, it would be greatly appreciated. But if you multiply field components together, Comsol multiplies the complex numbers together. Because the material is frequency dependent, the solver must be able to change the material value automatically every time when finding another eigen frequency. Jix Failed to evaluate expression. The name can be changed but the names of fields and I'm new to COMSOL and the RF module. For z-directed power, you would need to integrate emw. Jy and ec. Posted May 5, 2016, 2:36 p. 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 So in the Comsol model, we use the free space wave vector emw. The errors are coming since COMSOL is looking for "initial conditions" for the new physics variable to come from the stored solution, which doesn't contain any information on the new physics variables that have just been added to the model. - Variable: x - Global scope Failed to evaluate expression. I took a look at my variable files and comsol says that emw. k0 to specify the wave. dnTz How to integrate Far Field emw. <variable_name>. Are you using the 2D axi-symmetric formalism? If so, your working variables are already in cylindrical form. 0 3 Replies . It is thus not the same as the "norm" or magnitude, of the vector, in general. comp1. 1). Hy) -emw. emw. ec. - Variable: Col - Geometry: geom1 - Domain: 1 - Feature: Time-Dependent Solver 1 (sol1/t1) For instance, the absolute value of S21 (abs(comp1. 4 Click This module automatically generates variables for the S-parameters. normE - Plot: mslc1 (Multislice)" If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help. It is not recommended to use a reserved variable name for a user-defined variable, parameter, or function. Another way to calculate the Q factor at the dominant mode is via equations in Ref. 1) the (1) emw. Zport_1 actually returns a (wrong) real part only. k0sin(theta)sin(phi) (3) emw. Please login with a confirmed email address before reporting spam I need to write a COMSOL expression to extract a result value at particular spatial coordinates from one study, so that the I used the exact same script as the model in COMSOL for scaterring and in the absorption we see a peak, as expected, around 500nm (see Fig. ) Each component of the background field is defined as a Undefined value found in the equation residual vector. FORUM Why is the loss in unit "rad/m" when asking for emw. The following Electromagnetic Waves (emw) interface predefined variables are used in the table : emw. 5 for the fifth band, as determined by the nonlinear solver. Ey * conj(emw. relPoavx, emw. Ex * conj(emw. Failed to evaluate variable. These two methods seems equivalent to me. A plane wave propagating through free space (n = 1) as shown in Figure 1 is incident upon an infinite dielectric medium (n = 1. . (comsol feature) and an electric point dipole (comsol feature); two different sources of EMW, can have two different omegas in Note that while COMSOL employees may participate in the discussion forum, Although I defined all the initial and boundary conditions, I am having such a problem with my dependent variable, Col Undefined variable. Ex,x)+d(emw. They were able to calculate far-field variables with a built Searching Within a Model Using the Find Tool. Ey + nz * emw. Poavy When I try to compute the results it says it has encountered a problem with stationary solver 1(sol1/s1) and Failed to evaluate variable jacobian. 1, and is tuned to operate at 3 GHz. Stephen Holland . Consider that if the frequency response of the AWE - a global variable freq, defined by the solver, containing the frequency you wrote in the solver. CONTENTS| 5 Part Libraries 64 Chapter 3: Electromagnetics Theory Maxwell’s Equations 66 Introduction to Maxwell’s Equations . freq with the user-defined frequencies, different from each other and (potentially) from freq. Ex (in V5. Alternately, you can import variable definitions from a text file. When I'm processing results, say plotting 2D surface plots, COMSOL provides a list of expressions it can evaluate. normJR_0_n1 represents the Jones vector norm in 3D with mode numbers m = 0 and n = -1 for a port located on the same boundary as the exciting Periodic port. I'm a novice to use COMSOL. By setting a range of frequencies in the study: range( 4[THz], 0. Hi. S11 but This may be a stupid question, but I am brand new to COMSOL so please be patient with me. S2x. Send Private Message Flag post as spam. ny, -emw. The expression you just entered gives you the same in a logarithmic scale. dampzdB; BLOG Understanding Parallel Computing; KNOWLEDGE BASE Error: Failed to compute elastoplastic strain variables; KNOWLEDGE BASE What to do when a linear stationary model is not solving; KNOWLEDGE BASE Avoiding Negative Concentrations 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 COMSOL ® automatically You also have several global variables based on eigenvalue lambda and complex propagation constant alpha=-lambda for each mode, including the propagation constant, attenuation constant, and effective mode index. rho - Feature: Time-Dependent Solver 1 (sol1/t1) Is there someone you can tell my how to solve it? 10 On the Electric Field (emw) toolbar, click Plot. If the electric field is p-polarized — that is, if the electric . neff/r0)". Dear Comsol Community, I am looking for a way to find the location of the maximum of a variable. Ez) I suspect that this is due to the fact that the solver uses only the electric field as dependent variables. epsilonrxx, where tag is the tag of your physics interface, for instance emw for the Electromagnetic Waves, Frequency Domain interface in the RF Module. Then select the boundaries where the algorithm integrates the near field, and enter a name for the far electric field. ) are listed and explicitly defined? Hi Craig. freq - Defined as: freq Failed to evaluate variable. The design is realized as microstrip lines patterned onto a 0. normE)^2. When you plot (as opposed to compute with, in an expression) a quantity such as emw. Ephi FORUM sigst variable undefined; BLOG How to Compute Distances Between Objects in COMSOL Multiphysics® KNOWLEDGE BASE Undefined Variable; BLOG Performing Topology Optimization with the Density Method; FORUM COMSOL error: Cannot evaluate expression. Ex is the x component of E (not the gradient along x) of E. relPoavy, emw. But it would make more sense to me, that x, in this case, is drawn upon the pool of the limit range. Ez,emw. Note that while COMSOL employees may participate in the discussion forum, By multiplying the array factor equation to the antenna far-field gain variable, emw. Best regards, Mickaël Minna Theres James. This is why you get a different answer from using the longer expression. MODEL WIZARD 1 In the Model Wizard window, click 3D. Qsh). Thus, the variable emw. at coordinates: (0,0,0), and similarly for the degrees of freedom (empty columns in matrix). Posted Jun 20, 2011, 2:25 p. Efarz: far - field variable, z - component, V / m emw. curlEx" was defined as "emw. (We will talk more about this later. neff and some other variables that derive from the eigenvalue variable lambda (like dampz, dampzdB, beta and others). m. normE - Plot: mslc1 (Multislice)" If you still need help with To define the far-field variables use the Far-Field Calculation node. I perform a frequency domain study (Study 1: Frequency Domain) and I calculate the electric field inside a solar cell (due to the 'light') with an 'Electromagnetic Waves, Frequency Domain (emw)' node. Here, it is assumed that the dependent variable Failed to evaluate variable. Array Factor Function in the RF Module Typing a long expression of an Changing a variable in it, or picking a variable from it and using it to manipulate frequency in a specific boundary or domain is a wrong approach? My question was: can a plane wave generating boundary condition. - Variable: mod1. Ex, you only see the real part in your plot. nPoav represents the outgoing power flow through the boundaries where it is evaluated. The variable emw. For a conducting surface in air or vacuum, you could plot (nx * emw. Please login with a confirmed email address before reporting spam Failed to evaluate variable. EST Parameters, Variables, & Functions Version 5. Recall that the time harmonic ansatz in the COMSOL software assumes that the field components oscillate in time according to e^{j\omega t}, where \omega is the angular frequency. 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 - enter your variable you want to vary under control variables 3) add a frequency domain study node - within this node: - enter frequency start, step, stop same as in my experimental file The part I am having trouble with is that the optimization only finds the minimum value of the variable I am varying for the combined frequencies. Finally, Figure 4 shows the band diagram for k swept from 0 to 0. Zport_1. Is there some place where all the electromagnetic wave variables (i. Zport_1) = -10 Ohm or imag(), I'm new to COMSOL and the RF module. The solution is to create a new study sweeping over the acoustic and optical mode number In COMSOL Multiphysics ®, you can see the underlying governing equations for the physics in a model, as well as the definitions of the variables. This tag can be different for different physics interface instances. The expression shows up as orange, so I am guessing that there is an issue with the unit. 5 | BANDGAP ANALYSIS OF A PHOTONIC CRYSTAL Figure 3 shows the z-component of the electric field for k=0. The divergence of the Poynting vector: div(S) = (d(emw. k0 is. One cannot dream simpler example, yet it fails because " function toto is not found" or at least is it what comsol says. Poavz, z)) 4 | MODELING OF A CPW USING NUMERIC TEM PORTS NEW In the New window, click Model Wizard. To add an extra level of complexity, if anyone knows how to conduct a two parameter sweep, I would really appreciate this! If you are using V4. First of all, your equation has errors in the variable names. S21)) works great as the input for the AWE expression in the case of a two-port bandpass filter. 7 In the 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. Qfactor. Posted May 6, My plan is to define my own variable, say comp1. 2 Go to the Settings window for Built-in variables have reserved names, names that cannot or should not be redefined by the user. Hy -emw. Those variables are ultimately defined by the geometry, and can be plotted in an Arrow Line plot. 8 | FINDING THE IMPEDANCE OF A COAXIAL CABLE ©2011 COMSOL 5 Select Boundaries 11, 12, 16, and 19 only (the outer conductor boundaries). If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help. 5 * real(emw. In the Equationsection, the mathematical equations applica It provides tables listing common scalar and subdomain variables as well as boundary variables that describe physical properties like electric and magnetic fields, displacement, flux density, energy, and power flow. The document defines various electromagnetic variables and quantities that are available for postprocessing and for use in equations and What are emw. T - Feature: Time-Dependent Solver 1 (sol1/t1) Any thoughts on how to couple an ODE that defines a new variable with a variable already defined in COMSOL, in this case Temperature=T. normE - Geometry: 1 - Domain: 4 Failed to evaluate expression. Ey,x)'); trying to get the X position of the maximum Ey, it always goes wrong. 2a. Now define a variable for the characteristic impedance computed from the simulation. com) and include a description of what you are trying to model and the . For example, a lumped port with port number 1, defined in the first geometry, for the Electromagnetic Waves interface with the tag emw, defines the port impedance variable emw. COMSOL does not assume any legal liability for the accuracy of the data disclosed. How do i get comsol to recognize what emw. mat3. The dependent variables (field variables) are for the Electric field E and its components (in the Electric field components fields). gaindBEfar, you can compute the far-field gain of the antenna array. To open this tool, we either click the respective Find button on the Quick Access The variable is emw. curlEy" was defined as "-emw. ??. Hx. There are also variables for the norm of the Jones vector, named as tag. def. RF Coil : Application Library path RF_Module/Passive_Devices/rf_coil The function emw. k0sin(theta)cos(phi) (2) emw. Ex and model. iomega*( COMSOL ® automatically You also have several global variables based on eigenvalue lambda and complex propagation constant alpha=-lambda for each mode, including the propagation constant, attenuation constant, and effective mode index. I am a little bit confused and I would be grateful for your help regarding the calculation of surface charge density on a gold nanoparticle in glass in comsol (RF module). Hi I was performing a 2D simulation using the RF Module of COMSOL 5. normEfar over the solid angle defined by inclination (polar) angle theta form 0 to 60 degrees, and azimuthal angle phi from 0 to 360 degrees? IN DETAILS: I am simulating a nano 2) global variable: power_z = intop1(emw. Study 2 contains two stationary steps. E1 in Electromagnetic Waves of 4. These parameters can have a strong How do I access this variables? I know the overall wavevector is emw. Posted May 15, 2016, If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help. In the 2D axisymmetric formulation, There is a variable for the relative permittivity that you can use. 3 i use matlab comsol, i change the Lambda value each time for different simulation. neff Failed to evaluate variable Jacobian. Ez) * epsilon0_const which is the surface charge density that follows from Gauss' law. Poavy, y)+d(emw. How evaluate time when a variable assumes a given value . semi. 5 in the (1,1) direction. k But how is the vector called for i. I tried this with several other "random This equation does assume that one plate (or terminal) is held at a voltage V_0, while all other terminals in the model are grounded. 3 1 Reply . Please login with a confirmed The Name is used primarily as a scope prefix for variables defined by the physics interface. ** Note that while COMSOL employees may participate in the discussion forum, be evaluated as a volume integral of Energy density time average (emw. 0. Can we write them in parameters? And I think these components determine the direction of incident of light. Hz^2) which should be equivalent to emw. 3 2 Replies The variables ewm. ) are listed and explicitly The dependent variables (field variables) are for the Electric fieldE and its components (in the Electric field components fields). Note that while COMSOL employees may participate in the discussion forum, In this archived webinar, we focus on the use of COMSOL Multiphysics ® for modeling the interaction between electromagnetic waves and periodic structures. Figure 3: Z-component of the electric field for the fifth band and k = 0. I am running two different frequency domain studies (Solid Mechanics and EM), each one using a different component and after the computation is done, I would like to define a variable taking as expression the For the expression of incident wave in 'Scalar Variables', the wavevector k0 should be corrected as sqrt (epsilon)*k0, in which the epsilon is the permittivity of surrounding. COMSOL Certified Consultant AltaSim Technologies presented modeling work on Mie scattering by spherical particles at the COMSOL Conference 2013. The For mesh-case 0 there are 1 void equations (empty rows in matrix) for the variable comp1. COMSOL Moderator. The layout design is based upon Ref. I have attached a screenshot of the problem. ----- - Variable: freq - Geometry: 1 - Domain: 1 2 3 - Feature: Stationary Solver 2 (sol2/s2); - Error: Failed to evaluate variable Jacobian. 2 Replies Last Post Feb 4, 2011, 9:05 a. This magnitude is fixed, as the phase varies. txt) or read online for free. - Expression: x. mph in a test. nPoav variable refers to the component of the average power that is "normal" to (aka, perpendicular to) a particular surface. Regards, Sergei Nishant Shankhwar. Just right of the "Model Builder" heading theres an icon with an eye on it Undefined variable. This is somewhat confusing, because I would have expected Comsol to scale the wave vector automatically in a medium with "Ex" is fully defined as "root. COMSOL Multiphysics has a dedicated physics interface for this type of modeling — the Electromagnetic Waves, Frequency Domain interface. we would like to know,what is the reason behind the difference. nx, -emw. 6 Select the Description check box. I will post it here in hope that it will help other people. input. freq is COMSOL predefined variable, why the system cannot take it? I was using eigenvalue solver for eigen frequency study. Hy^2 + emw. Best regards, Ulf Failed to evaluate variable Jacobian. S1x at coordinates: (0,0,0), "It would be a very helpful if anyone can help or get the solutions for these errors Thank you in advance I don't know if COMSOL (in my case version 3. normE (electric field norm). However Read 6 answers by scientists to the question asked by Mohsen Dehqani on May 26, 2018 Failed to evaluate variable. 6 | FINDING THE IMPEDANCE OF A PARALLEL-WIRE TRANSMISSION LINE Modeling Instructions From the File menu, choose New. alphaOOP*Ey" and "emw. 4 Click Study. One example at a specific frequency: emw. I have attached a simplified version of my problem. EDT Low-Frequency Electromagnetics, RF & Microwave Engineering, Modeling Tools & Definitions, Parameters, Variables, & Functions, Studies & Solvers Version 4. maxDdB in the expression of a global evaluation, which is in the and direction. Er, emw. S1x in S-parameter definition; evaluating reflection/transmission on interior geometry. normE is the magnitude of the complex vector. Ey,y)+d(emw. In COMSOL 4. In the Physics and variables selection tree, select Component 1 (comp1)>Electromagnetic Waves, Frequency Domain (emw)>Perfect Electric Conductor 2. dnTx: Maxwell downward surface stress tensor, x-component. Wav) and the dissipated power can be evaluated as a surface integral of Surface losses (emw. S11dB in the 4. --Andrea Ferrario Electromagnetics Group When the Use check box is selected for the physics interface, in the section for the physics interface below the table, choose one of the four options for the Maximum mesh element size control parameter — From study (the default), How can I set the relevant variables for calculation in COMSOL? Specifically, it involves the cross product of the electric field and the conjugation of magnetic field, and I am not sure how to input the formula. freq changes according to the specified range. The first one involves just the electrostatics node (init), the second one involves an electrostatics node (es) and two transport of diluted species (cde, cdh). - Variable: comp1. Ebx as the background field, what are these two? Note that while COMSOL employees may participate in the discussion forum, COMSOL Same thing if I try to plot the norm using the expression sqrt(emw. - Function: / Failed to evaluate variable. 2 In the Select Physics tree, select Radio Frequency>Electromagnetic Waves, Frequency Domain (emw). 5a, for the 4. dnTx , emw. This enables you to: See how the variables are calculated by the software; See the names Hi I believe you are doing double up then, as for me: either you define the current flowing in the skin = boundary, and you ignore the domain (bulk), or you solve it fully in the domains (and ignore boundaries as materials) -Variable:comp1. I have already check the mesh,it's seem that For a changed definition of a variable or a change to a weak-form expression or constraint, a warning icon appears in the leftmost column, and a small padlock is added to the lower-right corner of the icon for the physics node where you have made modifications in its equation view. Ey in the expression field. For a rectangular cavity, the dominant mode is TE 101, at which the cavity provides the lowest Posted Feb 12, 2015, 7:10 p. thank you very much ，your The ewfd. Variables 1 1 In the Model Builder window, right-click Definitions and choose Variables. ny are the components of the normal to the boundary. Here, it is assumed that the dependent variable has been given the name E and that the tag for the physics interface is emw. 060 inch dielectric substrate. Type emw. Ey, emw. normdBEfar, etc. nz. relcurlEz - Geometry: 1 - Domain: 11 . COMSOL makes every reasonable effort to verify the information you view on this page. Ex * emw. 0a. Comsol Command Emw - Free download as PDF File (. If your antenna is driven by a port or lumped port, then the S11 parameter is available in the results. freq*(pi*2)) If you still need help with COMSOL and have an on-subscription license, COMSOL ® automatically You also have several global variables based on eigenvalue lambda and complex propagation constant alpha=-lambda for each mode, including the propagation constant, attenuation constant, and effective mode index. Getting the maximum value is easy, but so far I have not been able to get the coordinates of the maximum, preferably without using Matlab. Notice that band two and three are Posted Nov 24, 2013, 9:15 p. Qh - Geometry: 1 - Domain: 1 I've separated domain 1 from the Electromagnetic Waves module because that domain should not be supplying any heating in the model. V_init If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help. I am confused about setting the boundary conditions in Electromagnetic waves,Frequency domain (emw) module. In the Variables table or the fields under the table, enter variables by defining a variable name under Name, an expression that define the variable under Expression (see About Parameters, Variables, Variable Utilities, and Expressions), and (optionally) a description that explains the variable under Descriptions. Undefined variable. Returned solution is not converged. The name can be changed but the names of fields and dependent variables must be unique within a model. One solution is therefore to set Method: Initial expression Study: Zero solution MEF interface uses Maxwell-Ampère's law with displacement current included. emw. For this example, the values a = 2. There are 1 degrees of freedom giving NaN/Inf in the vector for the variable mod1. mph file (Clear the Division by zero. For some of the most common reserved variable names, such as pi, i, and j, the text where you enter the name turns orange and you get a tooltip message if you select The Name is used primarily as a scope prefix for variables defined by the physics interface. EDT RF & Microwave Engineering, Modeling Tools & Definitions, Parameters, Variables, & Functions, Results & Hello Deepshikha Bhargava Your Discussion has gone 30 days without a reply. N is Hi! When I click the show button and select the equation view in the RFmodule,from the equation view we can see many variables. Comsol support team helped me to find the solution to my problem. e domain 1 ? emw. but typically look something like emw. 5) and is partially reflected and partially transmitted. k0 is an unknown variable. Array Factor Function in the RF Module Typing a long expression of an I am using COMSOL V4. Can we write them in parameters? 2)Difference between domain backed and PEC slit type. es. And can we resolve this? emw. What actually their functions are and how would they affect the simulation? where \theta_f is the filtered design variable, \beta is the projection slope parameter, and p_\mathrm{SIMP} is the solid isotropic material with penalization (SIMP) parameter. I use EMW model to study about the absorption of solar cell(3D). Resources and documents are provided for your information only, and COMSOL makes no explicit or implied claims to their validity. In Component → Electromagnetic Waves, Frequency Domain → Wave Equation, Electric → Equation View, expanding the list of all variables, I found that "emw. Qh: total power dissipation density, W / m3 emw. Ey * emw. Posted May 21, Among all the variables, I don't know what these two mean. The video begins with a brief introduction to modeling electromagnetics in the software, highlighting the capabilities of various add-on products, including the RF Module and Wave Optics Module. For each variable name entered, the software generates functions and variables, which represent the vector components of the far electric field. I am beginner to comsol and using comsol 4. Hello Anurag Tiwari If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help. However,I encounter the problem about "Variables property does not include all variables in Xmesh". But how do I know what these are exactly? What, for example, is being plotted when I select emw. Poavx, emw. But assuming you are working in the frequency domain, what you really need to integrate is 0. NEW In the New window, click Model Wizard. In order to distinguish between variables belonging to different physics interfaces, the name string must be unique. Poavx, x)+d(emw. beta and emw. Send Private Message Flag post incident wave directions are -emw. Since we already have emw. I tried both from comsol and from comsol-with-matlab using livelink, after having converted the test. This problem does not happen with the electric field components (emw. dnTy, emw. To each of the generated variables, there is a Sso obviously the solver cannot recognize emw. i think because of the way comsol calculate lambda as C/F, and the C i used is 3e8, while, comsol used 2. The Settings window for the Current Conservation node, wherein the Equation section has been expanded. I think these variables can be used espesially in the data postprocessing. normE" at eps0 into the expression eps=eps0+A*mod(emw. normH. k ? Thank you! Jan . RF Coil : Application Library path RF_Module/Passive_Devices/rf_coil A Parameter might be overwritten later by COMSOL as a parameter is loaded once at first solver run and only updated via a "Parameter sweep" or "Continuation sweep" sovler node define variable “freq” and Hello Deepshikha Bhargava Your Discussion has gone 30 days without a reply. wee1. e. Ez,z))*n_glass^2 "Ex" is fully defined as "root. 11 From the Parameter value (m_azimuthal) list, choose 2. x series. T - Global scope: Failed to evaluate expression. For my application, how should I change the incident wave direction configurations I am new into COMSOL and i hope you guys can help me. Ex is the variable name, and is valid alone within the specified physics, the full name is root. Please response!!!! Failed to evaluate expression. freq, why?? emw. The names of these variables are constructed I am confused about setting the boundary conditions in Electromagnetic waves,Frequency domain (emw) module. epsilonrmZY Failed to evaluate variable. I get this message when a try to run the calculation : Undefined variable. Refer to such physics interface variables in expressions using the pattern <name>. But I need to get the directivity value (or gain value) at a certain direction such as and . freq and emw2. Ivar KJELBERG COMSOL Multiphysics(r) fan you have just hit the "implicit" indexing of COMSOL ;) 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. If the electric field is p-polarized — that is, if the electric In the model, I set a variable Var1=toto(1) and use this variable as a heat source on one of the domains. 0 or 4. The approximation is valid for Gaussian beams that have a beam radius that is much larger than the wavelength. 66 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. Since the paraxial Gaussian beam background field is an approximation to the Helmholtz equation, for 1) the (1) emw. EST. Ex, emw. 13 On the Electric Field (emw) toolbar, click Plot. If, for example, you have Hi all, For a far field domain antenna study, I can achieve the maximum directivity by typing emw. pdf), Text File (. But I don't understand what is wrong. 3 or something like that there is an example of a Mie scattering problem, phase-dependent scattering spectra? Posted Mar 13, 2014, 10:17 a. 13 Click Disable . normJX_Z, where X and Z represents the boundary location and mode number, respectively. normJR_0_n1 represents the Jones vector norm in 3D with mode numbers m = 0 and n = − 1 for a port located on the same boundary as the exciting Periodic port. There is a difference of three orders atleast. But I have noticed that often there are small errors when you import a model from 4. I would also advise to pay attention to the definition of the variables ewfd2. The port names (use numbers for sweeps to work correctly) determine the variable names. I am designing an adapter to transmit signal, which is with a main body, 3 rear For convenience, two variables for the S-parameters on a dB scale, S11dB and S21dB, are also defined using the following relation: In the table above, emw is the tag for the physics interface. k0*cos(phi) are put in variables. - Error: Failed to evaluate variable Jacobian. 0 Replies Last Post Feb 6, 2017, 12:46 a. freq” for frequency. 1. 286 cm, b = 1. Poavz, z)) where powerFlow is defined in Var2. I am designing an adapter to transmit signal, which is with a main body, 3 rear legs and 3 front legs. Hello I am a new comsol user 5. k0*sin(theta)*cos(phi) (2) emw. S11_z0, that does the same as emw. m where a and b are the dimensions of the waveguide’s aperture and d is the length of the cavity. Hx^2 + emw. 2 then a global variable probe exists with a name neff (emw. This variable is defined based on your input parameters for the Drude-Lorentz model. 1 and I am trying to model the deformation of a metal sheet under the influence of magnetic forces, caused by a time-dependent current on a (3D) coil. Ex", but within the node and sub nodes of EMW Physics "Ex" is sufficient, particularly because its a dependent variable But it you have another physics or another component (model) then you need the full names to allow COMSOL to find the correct path up and down the model set-up structural tree By multiplying the array factor equation to the antenna far-field gain variable, emw. EST RF & Microwave Engineering, Modeling Tools & Definitions, Parameters, Variables, & Functions Version 4. Select a domain for the far-field calculation. I've opened up equation view and can see emw. If I introduce a local cylindrical coordinate system comsol seems to change the solver to cylindrical coordinates but somehow I cannot access the data. The Name is used primarily as a scope prefix for variables defined by the physics interface. For the scattering plot, what I did was integrate over a surface the Far Comsol uses variable “emw. The tutorial says to use this variable to define ka. MODEL WIZARD 1 In the Model Wizard window, click 2D. For example, in the electromagnetic wave RF module, you have: emw. Ex + ny * emw. -Expression:d( For more help, please contact the COMSOL technical support. - Expression: comp1. Hx)). And using the constitutive relations and equation of continuity it obtains two equations in terms of A and V and solves for these variables. With the Find tool, we can search within a model for a parameter, variable, or even general text. so, i defined the lambda value by myself, example, from 1000nm to 2000nm with increment of 10nm. 3 or something like that there is an example of a There are also variables for the norm of the Jones vector, named as tag. Jx -Defined as:comp1. It is called tag. Ez))/A, which is an incorrect use of the syntax with three input arguments. dampzdB and use f0 as the expression for x-Axis Data. 5[THz], 6[THz]) means that variable emw. Maha Hashemi (emw. Only letters, numbers, and underscores (_) are permitted in the Name field. 1 You can see the equation for any physics node in your model by selecting the respective node and in the Settings window, expanding the Equationsection. 3 Click Add. The Q factor calculated in the stimulation is of the form emw. The approximation is valid for Gaussian beams that have a beam radius that is much larger than the If you want to create a variable that is the first time derivative you can use the "d"-operator. 12 From the Eigenfrequency list, choose 2. It's rather rapid, you can save your parameters and variables as txt files, you can save your geometry as a mphbin, and then quickly reload these in the new version. you exactly help me to solve this. S11)^2) but to my surprise the answers for T0 and R0 changed!!!! BTW, I also have a question related to the Plasmonic wire grating. omega - Defined as: (mod1. relPoavx is time average x-component of the Poynting vector of the scattered (or relative, in Comsol terminology) EM field. 5 While analysing the photonics crystal I am facing "Jacobian evaluation argument of realdot must be 0, 1, or -1" In your model, you have defined the variable nEz as intop1(realdot(emw. So personally I reconstruct my models in the new version systematically. In this case the solver automatically switched to nonlinear solver and converged solution obtained after few iterations. 0757E9. dnTx), [N] where intop1(): integration over particle surface, emw. k0*sin(theta)*sin(phi) (3) emw. x is defined in Parameters with some Value. The form of the branch line coupler is shown schematically in Figure 1. Poavz), which integrates the power density 'emw. powerFlow = abs(d(emw. Zport_1 = -10 Ohm real(emw. Fx=intop1(emw. 016 cm, and d = 1. Ex", but within the node and sub nodes of EMW Physics "Ex" is sufficient, particularly because its a dependent variable But it you have another physics or another component (model) then you need the full names to allow COMSOL to find the correct path up and down the model set-up structural tree You need to activate full precision to get both parts, or explicitly evaluate "imag(ewfd2. - two global variables emw. - Expression: d((mu0 const*mod1. (model, 'maxop1(emw. Available in the RF and Wave Optics modules, it uses the finite element You just need to add an x,y or z after the variable name to get the component you want. Poavz' over that area to give me the total power in the z-direction 'power_z'. BUT there is no need for you to do this anyway! while calculating Qfactor of aresonant cavity with metallic boundary the Q factor is not matching with calculated from analytically. Efarz and so forth. ec. Frequency Domain (emw) interface. By the way, I can get the all values manually by copying plot data of 2D or 1D far field radiation plots but it is In the Variables subnode, we also defined the scattering cross section, which is the surface integral of the Poynting vector. we can create global 1D plots of emw. . It means that the Scattering Boundary Condition will launch/absorb waves propagating orthogonally to the boundary. Note that this variable contains electric and magnetic components of the time- Posted Feb 17, 2016, 3:54 p. relPoavz: time average Poynting vector components of the scattered field, W / m3 emw. Posted May 13, 2011, 2:05 p. Jz in the external current density immediately become orange, with COMSOL claiming those variables are unknown. EDT MEMS & Nanotechnology, MEMS & Piezoelectric Devices, Modeling Tools & Definitions, Parameters, Variables, & Functions, Hi there. If, for example, there are two ports with the numbers 1 and 2 and Port 1 is the M = mphevalglobalmatrix(model,expr,) evaluates the global matrix of the variable expr and returns the full matrix M. Ez, emw. Qh under Wave Equation, but the expression for emw. alphaOOP*Ex". So i replaced my eps simply with eps=eps0+A*mod(emw. - Variable: pA - Geometry: geom1 - Domain: 2 Failed to evaluate Jacobian of expression. Here is how I get the surface charge density on the gold nano sphere surface (by using Gauss Law): Rho = (d(emw. If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base. S11 or emw. But are these variables all scalars?Or some are scalars and orthers are vectors?Besides,why there are only tangential electric field components,for COMSOL computes automatically the component in the propagation direction, if needed. 73 cm give a resonant frequency at the dominant mode, TE 101, of 10. 998e8. 4 0 Replies . To restore only the change in the selected variable, weak-form expression, or constraint, click the A plane wave propagating through free space (n = 1) as shown in Figure 1 is incident upon an infinite dielectric medium (n = 1. To get the correct out-of-plane electric field component, the variable emw. 5 In the Select Study tree, select Preset Studies for Selected Physics Interfaces> The variable emw. To create a material that can be applied to both physics and use the correct frequency, you need to use model Here is what I sent to COMSOL support as well: It looks like emw. COMSOL computes automatically the component in the propagation direction, if needed. Qh applies only domains 2, 3 For this geometry, applying separation of variables results in transcendental equations for the eigenfrequencies, and so this example serves as a benchmark for the 2D axisymmetric formulation. Derived Values Evaluate k2 to compare with the solutions obtained via separation of variables. mmoce owzmu bclkd gtiuaq gaorv rhofg iipvjtf wra ozbqvyt ccql