Uploaded June 2016 | Updated September 2026, 2 weeks ago
Check out some vortex generators in action on the wing of this Icelandair Boeing 767. I caught this video while flying from Keflavik to JFK. At first, I was taking a video of the inboard aileron, but then I noticed some vortices behind the vortex generators near the leading edge. After I zoom out a little, you can see where they originate from. Similar ones were visible behind the outboard vortex generators, but they were harder to see.
Make sure to turn the video quality all the way up so you can see the small vortex generators (they're hard to see if the video is slightly blurry).
Check out some vortex generators in action on the wing of this Icelandair Boeing 767. I caught this video while flying from Keflavik to JFK. At first, I was taking a video of the inboard aileron, but then I noticed some vortices behind the vortex generators near the leading edge. After I zoom out a little, you can see where they originate from. Similar ones were visible behind the outboard vortex generators, but they were harder to see.
Make sure to turn the video quality all the way up so you can see the small vortex generators (they're hard to see if the video is slightly blurry).
![Streamline Geometric Integral SPM [Mx(pj) and My(pj)]
We went through the derivations of the normal velocity geometric integral (Iij) and the tangential geometric integral (Jij). The Iij term is used in the expression to solve for the source panel strengths. The Jij term is used in the expression to solve for the velocity of the flow on each panel. In order to compute the flowfield around the airfoil (off the airfoil), we need to know the X and Y components of the velocity at arbitrary grid points (similar to a CFD solution).
In this video, we go through the derivation of the X and Y velocity geometric integrals (Mx(ij) and My(ij)). These will allow us to compute the flowfield pressure coefficients and the streamlines around the airfoil. Much of this derivation is exactly the same as the Iij derivation, so I will refer you to that video for those details.
RELEVANT VIDEOS
► Panel Methods Playlist
https://www.youtube.com/watch?v=bWjo3N9COz4&list=PLxT-itJ3HGuUDVMuWKBxyoY8Dm9O9qstP
► Panel Method Geometry
https://www.youtube.com/watch?v=kIqxbd937PI
► Building More Complex Flows
https://www.youtube.com/watch?v=EKzbwJvKcmw
► Flow Around an Airfoil
https://www.youtube.com/watch?v=cLdv1UfX1g8
► Normal Velocity Geometric Integral [I(ij)]
https://www.youtube.com/watch?v=76vPudNET6U
► Tangential Velocity Geometric Integral [J(ij)]
https://www.youtube.com/watch?v=JRHnOsueic8
NOTES
- Ill add notes here if I need to.
ERRORS
- If you see an error in the video, please let me know and I will include it here.
REFERENCES
Note: the links are Amazon affiliate links. If you do happen to want to buy the book and use the link below, it helps me out a little.
► Fundamentals of Aerodynamics, Anderson
https://amzn.to/3emVuXU
► Foundations of Aerodynamics, Kuethe and Chow
https://amzn.to/2yMg1Vi
► Theory of Wing Sections, Abbott and Doenhoff
https://amzn.to/2wvZyUt Streamline Geometric Integral SPM [Mx(pj) and My(pj)]](https://i.ytimg.com/vi/BnPZjGCatcg/mqdefault.jpg)
![Explained: Load CSV Data [MATLAB]
This video explains how to load CSV files into MATLAB using textscan. Explained: Load CSV Data [MATLAB]](https://i.ytimg.com/vi/CMaxsZoQuE0/mqdefault.jpg)
![Explained: Linear Interpolation [Math]
In this video, I explain how to obtain the equation for linear interpolation between two points. I then go through a simple example.
Linear interpolation can be useful when you need data at points where data does not exist. This happens a lot when looking at tabulated data. Here are some examples of tabulated data where linear interpolation can come in handy:
- Steam/vapor tables in thermodynamics
- Property tables in heat transfer
- Normal shock tables and isentropic relations tables in gas dynamics
In the video linked to below, I show you how to program this equation into a graphing calculator (TI-83), so you can use it on exams or whenever you need a quick estimate.
https://goo.gl/ntTuKl Explained: Linear Interpolation [Math]](https://i.ytimg.com/vi/Cvc-XalN_kk/mqdefault.jpg)

![Explained: Area-Mach Number Relation
Ever wonder why rocket nozzles have an hourglass shape, or why fighter jets use something called a converging-diverging nozzle? This video goes through one of the most fundamental concepts in compressible flow, and shows you why you need to first shrink down the area, and then expand the area to get supersonic flow.
NOTES
► When I talk about the choked flow, I didnt make it clear that you can increase the choked mass flow rate through the nozzle by increasing the stagnation pressure upstream of the nozzle. The mass flow rate will not increase only if you keep the same geometry and upstream stagnation conditions. That is, you cant increase the mass flow rate when the flow is choked by only decreasing the throat area and/or decreasing the back pressure.
► The flow will be sonic at the throat for isentropic flow (see the assumptions used in the derivation). This is not the case for real flows.
RELATED VIDEOS
→ 1D Mass Conservation
https://goo.gl/Wo8mcV
→ 1D Momentum Conservation
https://goo.gl/YJypbz
→ 1D Mass Conservation in Differential Form (Blog Post)
https://goo.gl/Q4ac2t
→ Speed of Sound
https://goo.gl/HPtH16
→ Sonic State
https://goo.gl/eou3aC
REFERENCES
► Notes by Matt MacLean
► Modern Compressible Flow, Anderson
► Elements of Gasdynamics, Liepmann and Roshko
► Gas Dynamics, Zucrow and Hoffman
THUMBNAIL PHOTO CREDIT
By NASA [Public domain], via Wikimedia Commons Explained: Area-Mach Number Relation](https://i.ytimg.com/vi/DRjWdDxVtRM/mqdefault.jpg)


![Explained: Airfoil Chord [Airplanes]
The airfoil chord is a vital part of understanding the angle of attack of an airfoil, as well as other aerodynamic parameters in aircraft design. The definition of the chord line is straightforward, while the definition for the leading edge (LE)/trailing edge (TE) are a little more ambiguous.
Second of All Comment
The first of all comment (that I made in the video) was that the angle of attack actually changes based off of where you define the leading edge to be. The comment I forget to say in the video is that the chord length also changes based on the LE location. For the minimum x value LE, the chord line is longer than the minimum radius of curvature LE. Explained: Airfoil Chord [Airplanes]](https://i.ytimg.com/vi/Eh5W61iswSY/mqdefault.jpg)

![In a Nutshell: Afterburners
Lets talk about what afterburners are, when theyre used, and how they work. In my first In a Nutshell video, Im testing the waters on giving simplified explanations for complicated topics. Let me know what you think.
RELATED VIDEOS
→ Detailed Afterburner Video
https://goo.gl/nt9KBp
REFERENCES
► Afterburners in The Aerothermodynamics of Aircraft Gas Turbine Engines, Zukoski
► Mechanics and Thermodynamics of Propulsion, Hill and Peterson
► Aerothermodynamics of Gas Turbine and Rocket Propulsion, Oates
► Aircraft Propulsion, Farokhi
► Aerospace Propulsion Systems, Ward
► Fundamentals of Jet Propulsion with Applications, Flack
THUMBNAIL PHOTO CREDIT
By United States Navy, Mass Communications Specialist 2nd Class Michael D. Cole [Public domain], via Wikimedia Commons In a Nutshell: Afterburners](https://i.ytimg.com/vi/EuITkZPd5c4/mqdefault.jpg)
