Scroll down for timestamps or use the links below to jump to the feature of interest to you. Note that this transcription has been edited for clarity.
Data Set Information
Contours and Surface Zones
Derived Objects of the Volume
Alan Klug: Good morning and thank you for logging into our Getting Started Tecplot 360 webinar. I’m Alan Klug, vice president of customer development here at Tecplot. And I’m here with Scott Fowler, Tecplot 360 product manager and Devon Simpson, technical product engineer, who will be doing most of today’s presentation.
I’ll let you read our bios if you’re interested but one thing to know about all of us is that we’re passionate about engineering and helping engineers and scientist make most of their Tecplot experience.
Before we jump right in, a couple notes. First of all, if you have any questions that arise during this presentation please type them in the chat box on the right side of the screen. We’ll shoot for about thirty minutes today but, even if we’re not able to get to your question during the presentation, we’ll make sure to get to it afterwards.
Additionally, this webinar is being recorded and a link will be emailed to you and be available for viewing. If you want to watch it again or share it with colleagues. Finally, I’m guessing the most people who are joining us today are familiar with Tecplot offer but for those that aren’t, Tecplot 360 is our flagship data visualization and analysis package. Tecplot Focus is another product which has a limited subset of Tecplot 360 functionality.
It’s commonly used by approximately 50,000 engineers and scientist for simulation and experimental data that they need to understand and share. Frequent use cases would be something similar to a fluids engineer who has CFD data they need to visualize. Or a test or PIV engineer who has thousands of data points that they need to analyze as well.
However, Tecplot 360 is extremely flexible and gets used in innumerable ways. With many data loaders, Tecplot can load almost all metric based 3-D data sets and virtually any data in text files. Again, we’re not a numerical modeling package or a CAD package. But if you need to visualize and analyze your data, Tecplot 360 is an excellent choice.
We’ll revisit this at the end of the webinar but if anything you see today makes you interested in acquiring, updating or upgrading a license or if you’re interested in personalized training. Please contact me at AlanKlug@tecplot.com
Now I’ll hand the presentation over to Devon, who will be showing you some of the foundational actions of Tecplot 360. Including the ability to load data, use our interface, explore zones, and drive objects, perform extractions, probes and mapping activities as well as export images, animation and files.
Tecplot is very easy to use and extremely powerful. So for new users or for users who haven’t had the opportunity to use Tecplot in a while, this should be a good introduction or reminder.
Thanks Devon. Take us away.
Origin of Rotation
Once we have the data loaded, to interact with it you can simply use the center mouse button to zoom in and out on the plot. You can also use the control right click to rotate your data.
By default, the data set origin of rotation is set to the center of the data. In this case, somewhere in the center in the center of the cylinder. Often times this isn’t correct so you can press and hold the o-key and left-mouse-click, which is a very useful key to set the center of rotation in this case to the back of the cylinder or to the front of the cylinder.
In this case, we’ve got several sections of data, and to turn those oranges boxes off we’re going to come into Options and Show Bounding Boxes for Enabled Zones with No Style. That will turn them off. I will show the edges to show the actual extent of our data set as we jump in and learn more about our data with data set info.
Data Set Information
Data Set information dialog is the home to the metadata about your data set. In this case, we’ve got 2,200 of what Tecplot calls zones. And these are just regions of connected information that represented an area of data on the plot. We also have variables here on the left side. So, the coordinate variables, the vector variables and then the fluid variables in RHO and E.
The next area is the zone type and information and in this case we have an ordered data set with IJK as the dimension of the Cartesian mesh. On the right side, you got variable ranges with minimum and maximum of both the currently selected zones and all active zones for this variable.
You can step through them and see then the variable ranges at this time. The final piece of information this Data Set info dialog is this Solution Time and Time Strand information here. Solution Time defines the current time step of this particular zone, and Time Strand identifies a particular region over time.
So for instance, this region is defined by the same strand “11” throughout time. So that way we can have the same style for that region as we step through time.
We have seen edges of the volume, but we call this section master switches of the data. I’ll turn off edge and then hop back into the mesh. So this then has turned on the mesh for only the cylinder so, I can zoom in and see the mesh.
There are three different places where you can control mesh properties.
The first is this master switch. Which will turn on and off mesh for every single zone surface that is currently being defined.
I can also right click on the zone and turn it on and off here and then, also basic things like color by variable or particular color on with the Right-click Context Menu.
The final location where I can control mesh properties is here in the Zone Style information, launched from the side bar. I can right click on one of these things on the mesh tab. I can change the mesh thickness to something a little bit thicker.
In Zone Style, you can also control more advanced properties, like contour, scatter, which points are currently being defined in the other properties in surfaces and volumes.
You might also notice that there are only fifteen elements here instead of the full two thousand and this is where the Time Strand has come in. As they advance through time, you might notice that the numbers here have updated when I’m on a new time step.
Contours and Surface Zones
Contour, however, is a little more complex. Contour is the way to color on a zone surface.
You can control contour properties from the Contour & Multi-Coloring Details dialog, where you have control over which variable is current being defined. The minimum and maximum for the range, which I’m going to set that to E currently, and you see how it updated on the plot. You can also use different color maps with the color maps option down here.
You might have noticed that I (accidentally) set it to contour group two. This is a place where you can set different variables quickly and easily across multiple styles. By default, everything uses contour group one. So you can then easily set everything at the same time to a new variable on your plot. Slices and surfaces will all be updated at the same time as you go through with each of these groups.
Derived Objects of the Volume
Now that we have seen how to tackle surface zones and work with surface zones. The next element of plot styling is working derived objects of the volume. So, these are slices, isosurfaces and streamtraces which are defined by specific points of the volume.
So we’ll start with slices. Slices are by default using the x-axis. In this case I’m really interested in looking at z-planes. That’s the perpendicular direction to my cylinder.
At this point you can start to see some of the vortices shedding off the back of the cylinder.
You can also use the Slice Plane tool. I’ll grab and position the slice plane with the positioning there.
You can animate through time and see the vortices shedding off of the back of the cylinder.
Note: “Drawing Interrupted” blank screen happens when you click on something when Tecplot is in the middle of drawing: If this happens at any time, you can simply click the center mouse button, or the redraw button in the side bar, to restore the plot.
We’ve got our slice defined and we’re looking at defining the isosurfaces next. I can turn them on and we’ve got a few isosurfaces, but the best way to define the value is to select the Probe tool.
Probe on a position that might be of interest. Grab this variable out of the probe value so we’re plotting by E. And I’m going to paste that into my isosurface value here. That should be a more detailed value of the vortices being shed off of the cylinder.
The final type of the derived object is streamtraces.
The first thing is to define the vector values. You have to inform Tecplot what vector values are being used.
My preferred way of defining streamtraces is using the rake tool. Which can be simply drawn on the plane.
Today I am showing volume ribbons which are a way to see the twist and turning of our values into this distance.
By default, volume lines are what are going to be generated when you use this rake tool on the surface. Which are simple lines. Those can be defined using this drop down here.
We’ve got Surface Lines, which are just on a single surface; Volume Lines, which go through the volume; and Rods and Ribbons, which are three-dimensional values that go through the area.
So, now we have a plot of interest. I can zoom into this region and animate through time and we can see these streamtraces, isosurfaces, and slice contours being defined as they go through time.
The power of Tecplot as a post-processing tool comes not only from the visualization, but also from its advanced analytic capabilities. The most basic analytics are found under Data > Alter > Specify Equations… And this is a place where we setup and create new variables using basic equations.
We have one I’ve already inserted here that calculates velocity magnitude with the vectors values that I have in my data set normalized by RHO.
You might notice that we are using curly brackets around each of the variables. The curly brackets define the extent of string and the variable name. When I compute here it will confirm that data alteration was successful. Then as I come into Data Set Info I can see the velocity magnitude added to my data set.
At this point I can then come into Contour Details dialog use my second contour group that was talking about earlier and set it to velocity magnitude. I can also then grab my isosurface and then use that same velocity magnitude as the contouring variable on that isosurface.
Tecplot can also extract and reduce the dimensionality of your data. Commonly used analytics tool are extractions. Extractions become really useful when you’re comparing multiple simulations against each other. Also when you are looking at a very specific metric such as mass flow rate.
Use the Data > Extract to extract slices, streamtraces and isosurfaces. You can also do all these same things over time.
Today our extraction is going to be a simple Tools > Probe To Create Time Series Plot. And this allows me to probe any location on the slice of my plot. I’m going to probe on the leading edge with my cylinder. And it will take that probe location and go throughout time.
Frames are a really useful tool in Tecplot. They allow you to have two plots next to each other and compare two different views of the data set.
As you click between the frames, you can see the plot side bar being updated as well as whichever frame is being updated here. So this frame side bar is really useful if you’re using multiple frames to control the location and which of your frames is currently active.
These two frames are also linked throughout time. You can see that this marker at the bottom will move when I animate through time. I’ll step all the way back to be beginning to restart the animation.
As I come into this plot, we’re actually also interested in looking at the x and y components of variables. I can then come into the Mapping Style dialog which is very similar to the Zone Style Dialog in two and three dimensions.
I’m going to select my RHO-U and RHO-V plots on the axis and then use this tool to create a set RHO-V on the y-axis. Use CNTL-S to fit the data to a specific plot. You can see how the RHO-U is being interacted with on the one side and the RHO-V with the other and how they correspond to each other.
At this point we have a presentation-quality plot and are ready to export it. There’s several ways to do this. The first is going through the Time Animation Details dialog and using the Export to file button under film strip icon on the dialog.
This will show the Export dialog which allows you to export to AVI, MPG-4, WMV and other video formats. Because I have two frames, I want to ensure that I’m exporting the current work area by setting Region to Work Area. And checking the Antialiasing checkbox which will sharpen up those lines.
I’m not going to actually do the export because that will take about two minutes to step through all of the data.
I will do a basic PNG export with the File > Export dialog and export the Work Area using Antialiasing. I can confirm that was exported by coming into my working folder and see that this the current plot that I exported there.
Note that Tecplot exports both vector and raster formats including: Postscript, encapsulated PostScript (EPS), and Windows Metafile formats. Export raster files in PNG, JPEG, BMP and TIFF formats. Configure image resolution independent of screen resolution.
Tecplot File Types: Saving and Restoring Layouts
Tecplot allows you to save and restore layouts. Three file types support this goal.
- Tecplot Layouts (.lay). LAY files save everything in the current session along with a link to the data.
- Tecplot Layout Packages (.lpk). LPK files save your layout along with a full copy of your data. These files are much larger than LAY files.
- Frame Style (.sty). Often more useful than layouts, is the frame style. It is available from Frame > Save frame style. I’m going to save the frame style as my 3-D plot. This file format saves only the style of the data of a single frame. It doesn’t save any links to the data.
To show how valuable this is, I’m going to turn off a few styles with my data sets and then rotate around. I can load that frame style it will restore my previous frame style.
So that’s some of the basic of Tecplot 360. In today’s demonstration we showed basic plot styling with mesh and contour, exploring the data via data set info, probing analytics data with creating an extraction through time and looking at multiple frames.
Alan Klug: Thanks Devon.
Question and Answer
Q: How can I use LaTeX labels in plots?
Devon Simpson: This capability was released in Tecplot 360 2017 R3. It’s pretty simple to use. All you would do is use this A/B button or a text tool insert button. It works the same way as a probing. You just select a location on the plot. It launches the Text Details dialog. Then select the LaTeX button in the top area of the Text Details dialog.
The LaTeX capability uses the LaTeX engine installed on your machine so it will use the same processes that you are familiar with using LaTeX in other applications.
Watch our video tutorial on Latex Fonts.
Alan Klug: So if you already have LaTeX installed that should be a pretty easy process.
Also, if you do have questions that have come during this presentation. Please do type them into the chat box we’ll keep looking at those and check a couple more here after were done with the ones we’ve already seeded.
Q: How do I make a slice perpendicular to a non-orthogonal surface?
We have a couple ways of doing that Devon will fill us in on.
Devon Simpson: So, the first way is using the Slice tool. When the Slice location is set to Arbitrary in the Slice Details dialog, the arrow will be displayed on the screen, which then can be interacted with.
The second way is to use the 3 Points dialog and click three locations. Tecplot will set the slice to go through those three points (although not perpendicular, it can be useful).
The third way is to paste the origin and normal directly into the Slice Details dialog, if you have those values.
Alan Klug: Great so if I know my normals already I should be able to just input those directly.
Q: Can I change the default startup settings?
Devon Simpson: Some of the settings can be set by default. Some of them are data set dependent so they cannot be set to a default value.
The first example is having lighting switched off by default. (Some people say that lighting distorts the color of the contours).
You can update Tecplot’s config file by adding macro commands to change the default settings. Tecplot reads and executes commands in the config file on startup.
I simply recorded a macro that turned off a lighting effect. I pasted it into my config file and now lighting is set to my specifications on startup.
Contours cannot be turned on by default because they are dependent on the data. However, you can use a quick macro to change the contours setting once you have loaded your data.
Alan Klug: And a couple things to mention about the config file to is that it’s seeded with many, many settings. So, usually if you just remove a comment it’s pretty easy to flip flop between defaults and as Devon mentioned, creating macros to do simple tasks like adjusting contour levels is very, very easy.
Q: How can I use python with Tecplot 360 to automate the data analysis process?
Devon Simpson: In Tecplot 360 2017 R3, we have the ability to record and then connect to a live Tecplot 360 instance.
Many seasoned users of Tecplot use the record macro capability, which uses our native Tecplot macro language.
We’ve added a Scripting > Record PyTecplot capability which will seed and create a Python script, that can be run either in batch mode or connect mode in Tecplot 360.
We’ve got quite a bit of introduction and documentation on our PyTecplot Web Page.
This is a cool feature and can get you started with scripting and automation really quick.
Q: How do I integrate MATLAB post processing with Tecplot 360?
Devon Simpson: We don’t have a direct capability to interact with MATLAB as we do with python. The best way to integrate MATLAB is to export data into a Tecplot-readable format and then read it into Tecplot.
And vice versa with getting data out of Tecplot into MATLAB. We created a webinar last spring on this exact subject. Watch Using MATLAB and TecIO to Read/Write Tecplot Data
Alan Klug: That’s a great resource.
Alright we have time for a couple of questions entered into the chat box. I know Scott Fowler has been typing away here while we’ve been talking. Hopefully answering a few people’s questions.
Scott, do we have any questions that would be appropriate to answer at this point?
Scott Fowler: Yeah. A few. I’ve answered quite a few privately. But let me just go over them because some of them are fairly interesting.
Q: How do I create isosurfaces through a 2D PIV data?
I think really the answer here is not isosurfaces so much as contouring. But the person who asks that question please add more detail if I’m not getting this quite right.
And you should be able to import it quite easily and do post processing activities. If you’re not with one of those vendors, you’re data is usually going to be structured. You may have a grid in say, x/y dimensions and you could bring that into Tecplot as a IJ-ordered data set. If you need help with that, we can certainly do that. Just contact us at email@example.com or if you’re an international customer go through your support channels (see our Distributor page). But we can certainly help you with that further if you don’t have Tecplot data format directly.
Q: How can I draw a slice only near the cylinder?
So, in that case, of flow around the cylinder, if you want to constrain that slice to a smaller region. The way you would do that in Tecplot today is what we call value blanking. In that data set, you would go through Data > Blanking > Value Blanking dialog, and you can just constrain the x and y dimensions using that. That will effectively reduce the size of that slice.
Now that does reduce the number of volume cells that you’re displaying as well. So this is where those data extractions that Devon was talking about are useful. You can then extract that slice and then turn value blanking back off and see the full extent of your domain.
Q: Is it possible to add CAD geometry to my data sets?
Yes. So, Tecplot has the ability to bring in multiple data sets into single frame. So you could have a CAD geometry and your simulation results combined into a single frame.
We do have a number of different readers. Devon showed you one with our SZL data reader. Which is our Tecplot format. But we do also have formats like STL. So if you have STL, that seems to be the best one for compatibility with Tecplot.
Q: I usually have cylindrical coordinates. Can I create surface of revolution at a radial location?
So, there are a couple of things here. So number one, you have the ability to transform coordinates. This is available via our macro language right now. And that can transform coordinates between Cartesian and cylindrical. If you do have a radius variable, you could always define an isosurface based on that radius variable to get something that looks cylindrical.
Q: Is there any way that I can turn on the accept Python connections by default?
Devon Simpson: Accept Connections is the way to opt-in to actually be listening. Python requires a socket connection to communicate, so, you can use your favorite IDE or command line script with Python. So that means on the Tecplot 360 side that you actually have to turn on listening so that you can communicate. To do this by default, you can start up Tecplot with a macro on the command line that includes a command to start listening.
Refer to the python documentation, but I believe the command is session.connect. See more in our Documentation.
Alan Klug: Well, Scott, we’re running out of time here. A little bit, we got a few minutes so far. Is there one more question we can answer?
Scott Fowler: Yeah. Well, there’s two more and we’ll do this really quickly. If any other questions trickle in, we’ll go ahead and answer those via email and, we’ll post the questions and answers online after the webinar.
Q: Can I limit the slices to go through just volume zones?
Yes. The setting by default is to have the slices go through only volume zones. You can have slices go through surfaces zones, that’s available on the Slice Details dialog. And there’s an entry in there called Slice Through and you can specify that there.
Q: How would I show visualization for a steady case file?
At each individual time step, think about a steady state. So, whatever we were showing on screen. If you had a steady state solution, you’d be able to get all the same visualizations options.
Alan Klug: Well, thanks everybody for participating in this webinar. We’re appreciate your time and interest in Tecplot.
Again if you do have questions about purchasing a licensing or upgrading an existing license or getting support on a license you already have please go ahead a shoot me an email.
My email is AlanKlug@tecplot.com and we look forward to interacting with you soon.
As Scott said, there are other questions that trickle in we’ll make sure those get answered.
But thank you again for your time and we appreciate it.