PROP_DESIGN Download:

PROP_DESIGN utilizes a new type of propeller theory that I created in January of 2020. PROP_DESIGN is unproven. It is up to the user to verify his or her designs. To do this, I recommend comparing the results you obtain with PROP_DESIGN against test data that you collect.

 

Last Updated On; 03/18/24

The final planned release of PROP_DESIGN was on 05/14/23. If any at all, future updates will be minor. Basically, after 15 years of continuous improvement, I'm done working on the project.

 

Below is a list of the most recent changes.

 

03/18/24 Update 2:

  • I did more compiler testing and I don't see any harm in doing the change mentioned earlier today. Therefore, I went ahead and implemented  it. Moreover, the latest upload no longer uses auto-vectorization and fuse multiply add (fma). Removing fma should greatly increase the amount of x86 processors that the codes can run on. This was always my highest priority. It simply never occurred to me that I introduced that limitation, until today. The performance difference for both of these features is too small for me to accurately capture. As always, you can get a little more performance, if you tune the c.bat files for your specific processor and recompile the codes. I also updated the benchmarking program, to make this easier for you. You can download that code on the 'Fortran Benchmarks' page (it's not part of the primary download)
  • I recompiled all of the *.exe files. So in most cases, you shouldn't need to compile the codes yourself
  • I temporarily added the 'Contact' page back to the website. This is so you can report any issues with the updated *.exe files

03/18/24 Update 1:

  • I updated all of the c.bat files and recompiled all of the codes. They may run slightly faster now. While working on this, it occurred to me that not all x86 processors have fused multiply add (fma) functionality. I currently have that turned on. It only provides a slight boost in performance. However, it will exclude a fair amount of processors. In the future, I may turn off fma functionality. If you find that you can't run the codes, this could be the reason why. To fix the problem, you would just deleted the /Qfma option from all of the c.bat files and recompile the codes. This would require you to have Intel Fortran installed

03/17/24:

  • Very minor updates to some of the documentation

01/09/24:

  • Added a new PROP_DESIGN logo to the user manual and overview documents. I created the logo for some of the website renderings
  • Updated the other LibreOffice Writer documents, in the documentation folder, so they all have the same page style now

01/01/24 (Happy New Year):

  • Tried to improve the 'PROP_DESIGN Geometry' notes page. Previously, when you zoomed in, the pictures were blurry. I was able to fix that problem. However, Mathcad is really bad at dealing with pictures. Now, the pictures are not readable at the default zoom range. So I can't really win. I think it's better now though. Being able to zoom in is helpful. If you find that an image isn't viewable, try changing the zoom percentage
  • Fixed an error on the 'Flow Angles' picture. There was an angle labeled 'theta' that should have been labeled 'theta 1'. The sketch is in the plane that the airfoil operates in. Which is the nz plane. I made that clear now. Angle theta is in the phi-z plane. So it doesn't apply to this particular sketch
  • Reorganized the 'Documentation' folder. Now, there are subfolders, whenever pictures are present
  • Updated more of the website images (I think I'm done with that)

12/28/23:

  • Minor improvements to the 'Airfoil Interaction Study' documentation
  • Updated more of the website images

12/24/23 (Merry Christmas):

  • Updated most of the website renderings to 1920x1080px
  • Updated the *.gif files, on the 'Concepts' page
  • Very minor updates to the documentation

12/10/23:

  • Tested Intel Fortran some more and optimized the compiler options further. I also compared Intel Fortran to gfortran and flang. As usual, Intel Fortran is much faster than gfortran. Currently, Intel Fortran is 3.6x faster than gfortran. By faster, I mean how fast the *.exe files (created by the compilers) run. There was no substantial difference between gfortran and flang runtimes. However, gfortran is better documented and has more compiler options
  • I recompiled all of the included *.exe files, using the updated c.bat files

12/09/23 Update 2:

  • Made a change to the default compiler options, to match the latest version of Intel Fortran. It seems that the /arch options changed slightly. Instead of generic, it is now SSE2

12/09/23 Update 1:

  • Intel is dropping their ifort Fortran compiler in favor of their newer ifx Fortran compiler. The compilers are different and the compiler options are different as well. I have been delaying the switch to ifx for as long as possible. However, Intel has decided that they will force the change upon everyone. Therefore, today, I did some more testing with ifx. The Intel ifx compiler only goes back to SSE3 extensions. The Intel ifort compiler goes back to SSE2 extensions. This would change the earliest supported CPUs from 2000 to 2004. Also, the Intel ifx compiler doesn't have an option to use precise square roots. These are the two biggest changes that would affect PROP_DESIGN. I am still holding off on switching to the ifx compiler, until it's absolutely necessary. Intel says this change will happen towards the end of 2024
  • Today's update brings a few minor source code note changes. I also recompiled all of the codes with Intel Fortran 2024.0.0. This compiler still supports ifort. So you can still run the included *.exe files on CPUs going back to 2000 (those that support SSE2 instructions)

12/01/23:

  • In the past, I noticed something odd regarding the way Gnuplot is branded. Their website uses both gnuplot and Gnuplot. It's not at all clear which it is. Originally, I used the lower case version. However, many years later, I switched to the other version. Today, I noticed that I didn't catch all of my references to gnuplot (lowercase). So I fixed those today. I still may not have found them all. Obviously, it doesn't really matter. However, it should be called something that's consistent. The changes, that I made today, were in the user manual and on the website
  • I also made some other minor website updates
  • Downloads and page views are still going at their historical rates. I'm always amazed at the international interest in the program. I'm really grateful for all of the interest. It justifies the tremendous amount of time that I spent working on the project
    • I've noticed that people interested in drones and marine propellers have been visiting the site. PROP_DESIGN isn't setup to handle these devices. They're something that could be added to the program, if someone were knowledgeable in those areas. My interest, knowledge, and experience was with aircraft propellers. So that's the focus of the program. The website makes this clear. However, people usually don't thoroughly read the website. So I figured I would mention it again. You would have to spend a lot of time writing code, to add new device types to the program. If you do create a modified version of PROP_DESIGN, to avoid any confusion, please call your program something other than PROP_DESIGN. I had an instance, in the past, where someone created a modified version of PROP_DESIGN and then claimed to have developed PROP_DESIGN. This really rubs me the wrong way. To this day, they still make this claim. I'm the only one who developed PROP_DESIGN. I spent a lifetime learning about propulsion and have had a passion for aircraft propellers for decades. Part of the reason I created PROP_DESIGN is to get good aircraft propeller design information out into the world. I want people to use and improve the program. I just don't want people claiming to have developed PROP_DESIGN. If you create a modified version of PROP_DESIGN, just figure out what you want to call it and state that's the program you developed. Hopefully, you can understand the distinction. There is no need for you to state that your program was based on PROP_DESIGN, unless that's something you want people to know
    • PROP_DESIGN was originally based on PROPSY. I like people to know this, for educational purposes. I spent many years studying all available aircraft propeller theories. So, I realize that knowing the lineage is helpful, if someone crazy like me comes along in the future. Of course, over time, PROP_DESIGN morphed into a completely different program. The underlying theory, that I created, is completely unique. The goal was to make it the best, by fixing all of the problems with previous aircraft propeller theories. Testing would be needed to find out if I achieved that goal or not. However, PROP_DESIGN is still the best learning point. If you use previous works, you will inherit their many problems and limitations

10/09/23:

  • Some of the XYZ input files weren't updated when they should have been. This is fixed now. The only difference is some of the most recent variable notes weren't present in some files. Now, all input files have the most recent variable notes

09/22/23:

  • Made a minor update to the legend of the ANGLE_COMPARISON plots. These are located in the ANALYSIS and ANALYSIS_MESH_TEST_TWO folders. The update helps the plots match the documentation better
  • Moved one of the spreadsheets, that was in the 'Calculators' folder, to the 'Airfoil Interaction Study' folder. The spreadsheet was created for use in the airfoil interaction study
  • Added a shortcut, to the 'Airfoil Interaction Study' folder, that points to the 'Airfoil CFD Needs' notes page. That particular notes page was created as part of the airfoil interaction study

09/15/23:

  • Added files, in the root directory, to automate compiling all of the *.exe files. Previously, you had to do this manually. There are 17 *.exe files. If you use the 'compileall.bat' file, 17 new windows will open and all of the *.exe files will compile in parallel. Make sure to run 'compileall.bat' from the 'Intel Fortran' command prompt, rather than a standard Windows command prompt. Obviously, you have to have Intel Fortran installed

09/14/23 Update 2:

  • Minor changes to ANALYSIS and ANALYSIS_MESH_TEST_TWO. Updated the data labels in the ANGLE_THETA_COMPARISON *.dat file. Also, updated the ANGLE_COMPARISON plots. These changes were made to better match the documentation updates from earlier today
  • Recompiled all *.exe files, using the latest version of Intel Fortran

09/14/23 Update 1:

  • Updated the 'Circulation' and 'Induced Velocity Calculations' notes pages

05/14/23 (Final planned release of PROP_DESIGN):

  • Minor documentation updates