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CAD Package for Electromagnetic and Thermal Analysis using Finite Elements FLUX 9.10 ® 2D Application Tutorial of electrostatics Copyright - January 2005 FLUX is registered mark FLUX software FLUX Tutorials : COPYRIGHT CEDRAT/INPG/CNRS/EDF : COPYRIGHT CEDRAT FLUX2D's Quality Assurance 9.1 version (Electricité de France standard, registered number AQM1L002) This tutorial was updated on 15 February 2005 by the EPM_NM Laboratory of the POLITEHNICA University of Bucharest Ref.: K205-C-910-EN-01/05 CEDRAT 15 Chemin de Malacher - Zirst 38246 MEYLAN Cedex FRANCE Phone: +33 (0)4 76 90 50 45 Fax: +33 (0)4 56 38 08 30 Email: cedrat@cedrat.com Web: http://www.cedrat.com CONVENTIONS USED To make this tutorial easier to read, we use the following typeface conventions: • All comments are written in the same way as this sentence • All dialog text between the user and FLUX2D is written in courier font: Name of the region to be created: magnet ↵ Colour of this region: MAGENTA Select a surface or a menu item: Quit [q]uit ↵ Below are presented the conventions used for the dialog between the user and FLUX2D: Italic text Bold text ↵ magnet ↵ [q]uit ↵ old text AGENTA Messages or questions displayed on the screen by FLUX2D User input to FLUX2D, such as the coordinates of a point The ↵ character symbolizes the Return/Enter key You only have to enter enough of the response to remove any ambiguity between the response you want and other valid ones In which case enter the character shown in square brackets [ ] FLUX2D menu input Make a selection by clicking on the menu item with the mouse or, if there is no ambiguity, by entering the first character of the word (shown in angled brackets < >) FLUX2D graphical input, such as selecting a line or a point ↵ The reply is by default To enter a default response, simply press the Return/Enter key - REMARK The files corresponding to different cases studied in this tutorial are available in the folder: .\ Doc_examples \ Examples \ Tutorials \ F2D91 _Tutorial_ Electrostatics The correspondent applications are ready to be solved This allows you to adapt this tutorial to your needs • If you are not familiar with FLUX2D yet, we advise you to run through this entire tutorial and to refer, if necessary to the given cases • If you are already a FLUX2D user, we advise you to redo only the PREFLUX 2D, SOLVER_2D and POSTPRO_2D sections, in order to discover the new possibilities of FLUX2D FLUX2D®9.10 TABLE OF CONTENTS TABLE OF CONTENTS REALIZED STUDY DEFINING THE PROBLEM 2.1 The geometry 2.2 The regions 2.3 The mesh .9 2.4 The materials .11 2.5 The boundary conditions .12 PREFLUX 2D: ENTERING THE GEOMETRY, THE MESH AND THE PHYSIC 16 3.1 Starting FLUX2D 16 3.2 Starting PREFLUX 2D 19 3.3 Entering the geometry 22 3.4 Building the mesh 65 3.5 Creating the regions and assigning physical properties 82 3.6 Creating the TRA file 106 3.7 Saving data and leaving PREFLUX 2D .106 SOLVER_2D: SOLVING THE PROBLEM 109 4.1 Starting the solver 109 4.2 Choosing the problem .110 4.3 Running the solver 111 POSTPRO_2D: ANALYSIS OF THE RESULTS 113 5.1 Starting POSTPRO_2D .113 5.2 Choosing the problem .114 5.3 Display of the results as charts 116 5.4 Computation of local and global quantities 123 5.5 Spatial variation of a local quantity 127 5.6 Saving the results in a text file 136 5.7 Leaving POSTPRO_2D .137 TUTORIAL OF ELECTROSTATICS PAGE A TABLE OF CONTENTS FLUX2D®9.10 SOLVER_2D: PARAMETRIC SOLVING PROCESS .141 6.1 Starting the solver 141 6.2 Choosing the problem 142 6.3 Definition of the parameters 144 6.4 Running the solving process 154 POSTPRO_2D: ANALYSIS OF THE RESULTS 157 7.1 Starting POSTPRO_2D 157 7.2 Choosing the problem 157 7.3 Analysis of the results 158 7.4 Leaving POSTPRO_2D 176 PREFLUX 2D: MODIFYING PHYSICAL PROPERTIES 179 8.1 Starting PREFLUX 2D 179 8.2 Creating a new problem 179 8.3 Creating and assigning the OIL material 181 8.4 Saving data and leaving PREFLUX 2D 183 SOLVER_2D: SOLVING PROCESS 185 9.1 Starting the solver 185 9.2 Choosing the problem 185 9.3 Starting the solving process 186 10 POSTPRO_2D: ANALYSIS OF THE RESULTS 187 10.1 Starting POSTPRO_2D 187 10.2 Choosing the problem 187 10.3 Display of the equi-potential lines 188 10.4 Computation of the energy in the LIQUID region 189 10.5 Leaving POSTPRO_2D 190 10.6 Conclusion 190 PAGE B TUTORIAL OF ELECTROSTATICS FLUX2D®9.10 PART A: DESCRIPTION OF THE STUDY PART A: DESCRIPTION OF THE STUDY TUTORIAL OF ELECTROSTATICS PAGE PART A: DESCRIPTION OF THE STUDY PAGE FLUX2D®9.10 TUTORIAL OF ELECTROSTATICS PART C: EXPLANATION OF CASE POSTPRO_2D: ANALYSIS OF THE RESULTS 7.4 FLUX2D®9.10 Leaving POSTPRO_2D We will save the path and the previously defined curves for a later analysis of the Eleliqra problem File Exit Yes PAGE 176 TUTORIAL OF ELECTROSTATICS FLUX2D®9.10 PART D: EXPLANATION OF CASE PART D: EXPLANATION OF CASE TUTORIAL OF ELECTROSTATICS PAGE 177 PART D: EXPLANATION OF CASE PAGE 178 FLUX2D®9.10 TUTORIAL OF ELECTROSTATICS FLUX2D®9.10 PART D: EXPLANATION OF CASE PREFLUX 2D: MODIFYING PHYSICAL PROPERTIES PREFLUX 2D: MODIFYING PHYSICAL PROPERTIES Case differs from Case only by the dielectric property of the LIQUID region, so it is useless to rebuild the geometry and the mesh You should only create and use another material for this region We will use the PREFLUX 2D program of FLUX2D to perform these modifications 8.1 Starting PREFLUX 2D To run the PREFLUX 2D program, you should double-click in the program manager on the Geometry & Physics module from the list of Construction tools of FLUX2D In order to keep the previous problem, we will create another problem with a different name 8.2 Creating a new problem We will open the ELE6WAT problem using the menus below: Project Open project … The Open window is then displayed and you must perform tasks and in the next figure TUTORIAL OF ELECTROSTATICS PAGE 179 FLUX2D®9.10 PART D: EXPLANATION OF CASE PREFLUX 2D: MODIFYING PHYSICAL PROPERTIES Select Ele6wat as PREFLUX 2D project name to open Click on the Open button to open the PREFLUX 2D project Then, we should save the ELE6WAT problem under the new name Eleoil by using the menus below Project Save as … The Save window is then displayed and you must perform tasks and in the next figure Enter Eleoil as PREFLUX 2D new project name Click on the Save button to save the PREFLUX 2D project under the new name 8.2.1 Activating the Physic context To modify physical properties, you should select the Physic context by clicking on the following icon: PAGE 180 TUTORIAL OF ELECTROSTATICS FLUX2D®9.10 PART D: EXPLANATION OF CASE PREFLUX 2D: MODIFYING PHYSICAL PROPERTIES 8.3 Creating and assigning the OIL material Now, we will create the new material OIL that will be assigned to the LIQUID region To create materials, you should follow the program sequence below: • either select the following menus: Physic Material New • • or click on the following icon: or in the tree at the left, in the Data tab: click with the right button of the mouse, in Physic, on Material The following contextual menus appear Select New • or double click on Material in the tree The New Material window is then displayed and to create the material OIL, you must perform tasks to in the next figure TUTORIAL OF ELECTROSTATICS PAGE 181 FLUX2D®9.10 PART D: EXPLANATION OF CASE PREFLUX 2D: MODIFYING PHYSICAL PROPERTIES Enter OIL as Name of the material Enter Mineral oil as Comment Select the D(E) tab Select Dielectic property Select Linear isotropic Enter 2.5 as Relative permittivity Click on the OK button to create the material Click on the Cancel button to quit this window The OIL material is then created Now, we will choose OIL as new material for the LIQUID surface region You should follow the command sequence below: • in the tree at the left, in the Data tab: click with the right button of the mouse, in Physic, in Regions, on Face region The following contextual menus appear Select Edit array PAGE 182 TUTORIAL OF ELECTROSTATICS FLUX2D®9.10 PART D: EXPLANATION OF CASE PREFLUX 2D: MODIFYING PHYSICAL PROPERTIES Then you should perform tasks to in the next figure Select OIL as material of the region Click on the OK button to save the modification The modification is finished and the data will be recorded in the ELEOIL.TRA transmission file by the following commands: • select the following menus: Project Export Export physic Export physic to a TRA file (Flux2D) To create the TRA file associated to the current project, you must perform tasks to in the next figure Enter eleoil as PREFLUX 2D project name Click on the OK button to save the PREFLUX 2D project 8.4 Saving data and leaving PREFLUX 2D To save the data of the current project you should: • either select the following menus: Project Save • or click on the following icon: TUTORIAL OF ELECTROSTATICS PAGE 183 PART D: EXPLANATION OF CASE PREFLUX 2D: MODIFYING PHYSICAL PROPERTIES FLUX2D®9.10 Saving project 'C:\CEDRAT\TUTORIAL\2D\TUTORIAL_91\ELECTROSTATICS\Eleoil.FL U' 11:36:52 1522 sec Start save 11:36:58 1529 sec end save 11:36:58 1529 sec End writing end saving project At this moment, you can solve the new problem PAGE 184 TUTORIAL OF ELECTROSTATICS FLUX2D®9.10 PART D: EXPLANATION OF CASE SOLVER_2D: SOLVING PROCESS SOLVER_2D: SOLVING PROCESS We will solve the ELEOIL problem, without parameters, using the SOLVER_2D program of FLUX2D 9.1 Starting the solver To run SOLVER_2D, you should double-click in the program manager on the Direct module from the list of Solving process tools of FLUX2D 9.2 Choosing the problem In the Open window you should click on the name of the problem to be solved, Eleoil.tra, then on the button Open: Eleoil.tra Open TUTORIAL OF ELECTROSTATICS PAGE 185 FLUX2D®9.10 PART D: EXPLANATION OF CASE SOLVER_2D: SOLVING PROCESS 9.3 Starting the solving process To start the solving process you should click either the icon menus: , or in the solver task-bar on the Computation Solve The Output data box is displayed on top It contains information about the solving process The History window at the bottom of the screen contains information about the evolution of the solving process Size of the matrix: Number of lines = 5778 Average length = Integration done, equations assembled Equations solved Status: computation finished The end of the solving process is announced by a message in the Output data box, as well as in the History window To quit the solver, you should click on the following menus in the task-bar: File Exit PAGE 186 TUTORIAL OF ELECTROSTATICS FLUX2D®9.10 PART D: EXPLANATION OF CASE POSTPRO_2D: ANALYSIS OF THE RESULTS 10 POSTPRO_2D: ANALYSIS OF THE RESULTS Now, that you are accustomed with POSTPRO_2D module, we are going to verify the most important results 10.1 Starting POSTPRO_2D To run POSTPRO_2D, you should double-click in the program manager on the Results module from the list of Analysis tools of FLUX2D 10.2 Choosing the problem To open a problem, you should click either on the icon , or in the post-processor menu-bar on: File Open In the Open box already displayed you should click on the name of the problem to be analyzed Eleoil.tra, then on the button Open: Eleoil.tra Open TUTORIAL OF ELECTROSTATICS PAGE 187 FLUX2D®9.10 PART D: EXPLANATION OF CASE POSTPRO_2D: ANALYSIS OF THE RESULTS 10.3 Display of the equi-potential lines To display the equi-potential lines, you should click on the icon , or on the menus: Results Isovalues To visualize the lines and the corresponding legend, click on the menus: View Legend window PAGE 188 TUTORIAL OF ELECTROSTATICS FLUX2D®9.10 10.4 PART D: EXPLANATION OF CASE POSTPRO_2D: ANALYSIS OF THE RESULTS Computation of the energy in the LIQUID region We are going to compute the energy in the LIQUID region To compute the stored energy and coenergy in this region, you should open a computation on a support manager by clicking either on the icon , or on the menus: Computation On a support Then, you should execute tasks to presented in the following figure Verify that the Filter is Regions Select the Liquid region as Support Click on Properties Select Energy as Quantity Click on Add All Click on OK Click on Compute to start the computation of the energy TUTORIAL OF ELECTROSTATICS PAGE 189 FLUX2D®9.10 PART D: EXPLANATION OF CASE POSTPRO_2D: ANALYSIS OF THE RESULTS The results corresponding to the LIQUID region are displayed in the following window Note: The energy (and also the co-energy) stored in the LIQUID region is lower than the value corresponding to case 1, because the new OIL material has a relative permittivity lower than that of the WATER material in Case 10.5 Leaving POSTPRO_2D File Exit Yes 10.6 Conclusion This tutorial has allowed you to accomplish your first steps in FLUX2D It is up to you to proceed to other computations or result analysis, modify the geometry or the physical properties presented in this tutorial, PAGE 190 TUTORIAL OF ELECTROSTATICS