JoshTheEngineer | How To: Find Mach Number from a Picture (Part 1) @JoshTheEngineer | Uploaded January 2016 | Updated October 2024, 7 hours ago.
Want to look at a picture of a bullet/plane/etc. and be able to approximate the Mach number? In this video I show you three ways to find the Mach number from a Schlieren image.
Disclaimer: The Mach numbers I obtain are, as mentioned in the video, approximations. I understand that they will not be entirely correct, but these methods can be used to get good initial estimates.
Last Photo Note: On the news article (cited below), they state that the plane reached a maximum Mach number of 1.09. However, there was a Reddit post from someone who worked on the team that took the pictures, and he states the plane was flying at just under Mach 1.2 when the photos were taken. Here is the link to that post:
reddit.com/r/pics/comments/3iuouf/this_is_what_piercing_the_sound_barrier_looks_like/?limit=500
1st Photo Credit
By Settles1 (Own work) [CC BY-SA 3.0 (creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons
2nd/3rd Photo Credit
School of Aerospace, Mechanical and Mechatronic Engineering
University of Sydney, 1998-2004
4th Photo Credit
Tumblr: jefflownsbury-blog
5th Photo Credit
By NASA Langley Research Center, X-15 testing
6th Photo Credit
By NASA Glenn Research Center [Public domain], via Wikimedia Commons
7th Photo Credit
NASA photo
nasa.gov/centers/armstrong/features/shock_and_awesome.html
Want to look at a picture of a bullet/plane/etc. and be able to approximate the Mach number? In this video I show you three ways to find the Mach number from a Schlieren image.
Disclaimer: The Mach numbers I obtain are, as mentioned in the video, approximations. I understand that they will not be entirely correct, but these methods can be used to get good initial estimates.
Last Photo Note: On the news article (cited below), they state that the plane reached a maximum Mach number of 1.09. However, there was a Reddit post from someone who worked on the team that took the pictures, and he states the plane was flying at just under Mach 1.2 when the photos were taken. Here is the link to that post:
reddit.com/r/pics/comments/3iuouf/this_is_what_piercing_the_sound_barrier_looks_like/?limit=500
1st Photo Credit
By Settles1 (Own work) [CC BY-SA 3.0 (creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons
2nd/3rd Photo Credit
School of Aerospace, Mechanical and Mechatronic Engineering
University of Sydney, 1998-2004
4th Photo Credit
Tumblr: jefflownsbury-blog
5th Photo Credit
By NASA Langley Research Center, X-15 testing
6th Photo Credit
By NASA Glenn Research Center [Public domain], via Wikimedia Commons
7th Photo Credit
NASA photo
nasa.gov/centers/armstrong/features/shock_and_awesome.html
![Explained: Lift Curve [Airplanes]](https://i.ytimg.com/vi/tF_Z1lz7HKw/hqdefault.jpg "Explained: Lift Curve [Airplanes]
Lift curves are available for various airfoils and provide data relating the lift coefficient of the airfoil to the angle of attack. The lift curves described in this video are for 2D (infinite wing) airfoils. Actual 3D wing lift curves are complicated by 3D effects such as spanwise flow and tip vortices. See the links below for actual NACA data for both a symmetric and a cambered airfoil.
Angle of Attack:
https://www.youtube.com/watch?v=Fm2Az-PgPUU
NACA 0012 (Symmetric):
- The lift curve to look at is the lower of the two sloped lines
- Notice that at zero AoA, the lift coefficient is zero
- The horizontal lines are moment coefficient plots, which you can ignore for now
http://mshades.free.fr/flapping/Cz0012.jpg
NACA 2412 (Cambered):
- Lift curve is the left of the two plots
- Notice that the zero lift AoA is negative (approx. -2 degrees)
http://www.tricity.wsu.edu/htmls/mme/me439/s2007/naca2412.jpg")
![Explained: Rain Gutters [Airplanes]](https://i.ytimg.com/vi/u4FNaPu9-hQ/hqdefault.jpg "Explained: Rain Gutters [Airplanes]
Rain gutters are little strips of material above doors that allow you to stay dry as you get on or off a plane. They also help keep the interior of the plane dry.
Horizontal rain gutter:
http://www.airliners.net/photo/Untitled-%28Trans-World/Lockheed-L-1011-385-1-TriStar/0197040/L/&sid=030cda10fed5df9cd077f6437194798e
Slanted rain gutter:
http://www.airliners.net/photo/Trans-World-Airlines/Lockheed-L-1011-385-1-15-TriStar/0689474/L/&sid=030cda10fed5df9cd077f6437194798e")
![Explained: Taylor-Maccoll Conical Flow Overview [Taylor-Maccoll]](https://i.ytimg.com/vi/v3EqbYGI_Hg/hqdefault.jpg "Explained: Taylor-Maccoll Conical Flow Overview [Taylor-Maccoll]
This is the first video in a series of videos about the supersonic flow over a cone at 0 degrees angle of attack. This is also known as Taylor-Maccoll conical flow, after the two guys that derived the equations and obtained solutions for this type of problem.
This video aims to introduce the general problem description and lay out the basic steps for the derivation/solution. More videos will follow as described in the video.")
![Explained: Slider GUI [MATLAB]](https://i.ytimg.com/vi/wGaPLzaHIps/hqdefault.jpg "Explained: Slider GUI [MATLAB]
This video explains how to code a slider in a MATLAB GUI. It also shows how to change the Min, Max, and Value arguments to alter the range of the slider.")
![Explained: Tilde to Discard Output [MATLAB]](https://i.ytimg.com/vi/wg7GTwsZL-Q/hqdefault.jpg "Explained: Tilde to Discard Output [MATLAB]
Sometimes functions return too much information, or more than you need/want. To suppress some of the output and keep your code clean, you can use a tilde in the place of variables.")
![Explained: NACA 4-Digit GUI Part 4/10 [MATLAB]](https://i.ytimg.com/vi/x8ls10Euy-k/hqdefault.jpg "Explained: NACA 4-Digit GUI Part 4/10 [MATLAB]
This is the fourth video in my 10-video series on coding a program in MATLAB to compute, display, and save a NACA 4-digit airfoil.
IN THIS VIDEO:
We code the airfoil type callback. This edit text box reads in the string of the airfoil that the user wants to compute and plot. After we read in the value of the airfoil, we check to make sure that it is only four digits. If more or less, it displays an error message and makes sure the airfoil cant be plotted.
IN THIS SERIES:
Part 1/10 : https://goo.gl/9UBgbo
Part 2/10 : https://goo.gl/jRRcYJ
Part 3/10 : https://goo.gl/rSVLHo
Part 4/10 : https://goo.gl/HwHB39
Part 5/10 : https://goo.gl/AlDne8
Part 6/10 : https://goo.gl/7n1QP7
Part 7/10 : https://goo.gl/nTGleR
Part 8/10 : https://goo.gl/ez247P
Part 9/10 : https://goo.gl/8mXYcc
Part 10/10: https://goo.gl/ovBlbW")
