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EasyFlowfield Tutorials

SmartNumerics Simulation Solutions Inc.

Copyright SmartNumerics Simulation Solutions Incorporated, 2020, All Rights Reserved.

Table of Contents

1. Introduction to Using the GUI and Running Simulations
2. Tutorials
3. Copyright and Trademark Information

1.0 Introduction to Using the GUI and Running Simulations

EasyFlowfield stores the details of each simulation in a text file with file type script. The script file is produced and modified using the GUI. New versions of a script file can be compared to old versions of the script file using one of the many text comparison utilities available on the internet.

Buttons under each menu heading can be used to create or modify the script controlling execution of the EasyFlowfield solver. Clarifying hints can be obtained by placing the cursor over the menu buttons. In most cases, clicking on a menu button will either produce an input dialog box or a dialog list that allows creation and editing of multiple input dialogs. Each dialog typically contains a set of parameters with associated text boxes. To paste text or numbers into a GUI text box, left click on the text box and press Ctrl+v. To copy text, select it and press Ctrl+c. The Delete key and the commands Ctrl+x (cut) and Ctrl+a (select all) can also be used.

The script is constructed by going from left to right usually starting at menu heading SOLUTION. A series of dialogs are created to produce the script. The values specified in a dialog do not have effect until the dialog is closed. The current dialog must be closed before another one is opened. After it has been constructed, the script must be saved before the simulation can be run.

This document contains links to a number of tutorials. The tutorials should be performed or read in the order listed to get the best possible understanding of the operation of the GUI and the solver. The early tutorials cover iteration to the steady-state condition. Some later tutorials cover production of time-accurate simulations.

Each of the tutorials has been selected to demonstrate some aspect of the GUI and solver. Thus, some or all should be performed before attempting a simulation of personal interest. More information and advice can be obtained by looking under help for each menu heading.

To run the simulation interactively, select Interactive Simulation under menu heading FILE. A DOS window will open, and details of input and execution will appear as they occur. This option will run the current script file. Information in the DOS window can be copied by selecting text using the left mouse button and then clicking on the right mouse button. The font size or maximum number of lines that are visible in the DOS window can be increased by clicking on the top left-hand corner and selecting various options.

If you instead select Background Simulation, a DOS window will appear to display a summary of execution and details of the input and execution will be sent to a listing text file. Select Open Current Listing under menu heading FILE to view the listing. This option will show the current script file.

If you instead select Automated Simulation, a DOS window will appear to display a summary of execution and details of the input and execution will be sent to the listing text file. The name of the current script will be ignored. Instead, the script test.script will be run. If the script restart_test.script exists, it will be run after the end of execution of test.script.

You may run more than one simulation at a time as long as a different project folder is used for each simulation. However, execution time will be adversely affected if you exceed the memory on your PC. In addition, it is best to use a multicore PC, so that each simulation is handled by a separate core. When using a four-core PC, it is best to run less than four simulations so at least one core is free to handle other tasks.

In the following examples, the flow-field values are usually output using the ParaView file format (.vts) while other values are output using a Microsoft Excel file format (.csv). Other file-format options such as Tecplot and DPlot are discussed in help under menu heading OUTPUT.

Microsoft Excel is suitable for plotting 1D solutions or the history of a quantity. In order to plot output using Microsoft Excel, you must select the ‘x-y scatter plot’ option. The other options force all input variables to be dependent variables. New variables can be calculated from the variables read from the .csv file. You can create a secondary axis for some of the dependent variables. With some experimentation, you can create macros to partially automate the creation of plots.

ParaView is an open-source data analysis and visualization application that can read .vts text files output by EasyFlowfield and produce colour contour plots for 2D and 3D simulations. If plotting the solution from a 1D simulation, apply the ‘Plot Data’ filter, disable ‘Use Index for Axis’, and set the ‘X Array Name’ to the x-coordinate. New variables can be calculated from the variables read from the .vts file. Flow variables along a given row of cells or nodes in a 2D or 3D grid can be selected using the ‘Extract Subset’ filter and can be exported to a .csv file. You can create macros and/or state files to partially automate the creation of plots.

The Excel .csv format can also be read by ParaView. After reading the .csv file into ParaView, apply the ‘Plot Data’ filter, and disable ‘Use Index for Axis’. Set the ‘X Array Name’ to the x-coordinate if plotting a 1D solution and to time, cycles, or work if plotting the history of a quantity. You can specify the variables to be plotted, select the line pattern, select symbols, and customize the range of values on the x or y axis. Values from multiple .csv files can be placed on the same plot. A variable may be assigned to the right axis by highlighting it in the ParaView list of variables and specifying ‘Bottom-Right’ instead of ‘Bottom-Left’. Experimental values or reference data stored in text files may use the .csv format but should be stored using a filetype of .txt since EasyFlowfield deletes files with filetype .csv in the output folder when initiating a simulation.

The following video may be of interest.

2.0 Tutorials

Only some of these tutorials can be performed if you only posses an EasyFlowfield Basic license. EasyFlowfield Basic only allows use of the two rectangular Cartesian grid dialogs and the o-grid dialog. It does not allow import or export of grids. Thus tutorials 2, 3, and 4 should be skipped.

3.0 Copyright and Trademark Information

EasyFlowfield is a copyright of SmartNumerics Simulation Solutions Incorporated.

ParaView is a copyright of National Technology & Engineering Solutions of Sandia, LLC Kitware Inc.

Excel is a Microsoft Corporation trademark.

DPlot is a copyright of HydeSoft Computing LLC.

Tecplot is a trademark of Tecplot Inc.