![Explained: Area-Mach Number Relation [CPG] @JoshTheEngineer](https://i.ytimg.com/vi/bdcxN0u5hMs/maxresdefault.jpg)
Uploaded October 2017 | Updated September 2026, 2 weeks ago
Can we approximate the exit Mach number of a rocket nozzle knowing only the area ratio? With a few assumptions, we certainly can! In fact, if we know how the area changes along a nozzle from the throat to the exit, we can calculate how the Mach number varies throughout the entire nozzle.
===== NOTES =====
► I'll make sure to never use my orange marker again
► If you download my Method of Characteristics MATLAB code from my GitHub (link below), you can see that the results of both match very closely!
===== HOW TO SOLVE AREA-MACH NUMBER RELATION =====
joshtheengineer.com/2016/11/16/solving-the-area-mach-number-relation
===== ROCKET NOZZLE - METHOD OF CHARACTERISTICS =====
github.com/jte0419/Rocket_Nozzle_Design
===== RELEVANT VIDEOS =====
Area-Mach Number Differential Form
goo.gl/tDzBtM
Sonic State
goo.gl/j6yCxD
Stagnation-to-Static Relations
goo.gl/r5JZSQ
Normal Shock Relations
goo.gl/E5Lwac
===== REFERENCES =====
► Notes by Matt MacLean
► Modern Compressible Flow, Anderson
► Elements of Gasdynamics, Liepmann and Roshko
► Gas Dynamics, Zucrow and Hoffman
===== THUMBNAIL IMAGE =====
By NASA (mix.msfc.nasa.gov/abstracts.php?p=2388) [Public domain], via Wikimedia Commons
Can we approximate the exit Mach number of a rocket nozzle knowing only the area ratio? With a few assumptions, we certainly can! In fact, if we know how the area changes along a nozzle from the throat to the exit, we can calculate how the Mach number varies throughout the entire nozzle.
===== NOTES =====
► I'll make sure to never use my orange marker again
► If you download my Method of Characteristics MATLAB code from my GitHub (link below), you can see that the results of both match very closely!
===== HOW TO SOLVE AREA-MACH NUMBER RELATION =====
joshtheengineer.com/2016/11/16/solving-the-area-mach-number-relation
===== ROCKET NOZZLE - METHOD OF CHARACTERISTICS =====
github.com/jte0419/Rocket_Nozzle_Design
===== RELEVANT VIDEOS =====
Area-Mach Number Differential Form
goo.gl/tDzBtM
Sonic State
goo.gl/j6yCxD
Stagnation-to-Static Relations
goo.gl/r5JZSQ
Normal Shock Relations
goo.gl/E5Lwac
===== REFERENCES =====
► Notes by Matt MacLean
► Modern Compressible Flow, Anderson
► Elements of Gasdynamics, Liepmann and Roshko
► Gas Dynamics, Zucrow and Hoffman
===== THUMBNAIL IMAGE =====
By NASA (mix.msfc.nasa.gov/abstracts.php?p=2388) [Public domain], via Wikimedia Commons
![Explained: Area-Mach Number Relation [CPG]](https://i.ytimg.com/vi/bdcxN0u5hMs/mqdefault.jpg "Explained: Area-Mach Number Relation [CPG]
Can we approximate the exit Mach number of a rocket nozzle knowing only the area ratio? With a few assumptions, we certainly can! In fact, if we know how the area changes along a nozzle from the throat to the exit, we can calculate how the Mach number varies throughout the entire nozzle.
NOTES
► Ill make sure to never use my orange marker again
► If you download my Method of Characteristics MATLAB code from my GitHub (link below), you can see that the results of both match very closely!
HOW TO SOLVE AREA-MACH NUMBER RELATION
http://www.joshtheengineer.com/2016/11/16/solving-the-area-mach-number-relation/
ROCKET NOZZLE - METHOD OF CHARACTERISTICS
https://github.com/jte0419/Rocket_Nozzle_Design
RELEVANT VIDEOS
Area-Mach Number Differential Form
https://goo.gl/tDzBtM
Sonic State
https://goo.gl/j6yCxD
Stagnation-to-Static Relations
https://goo.gl/r5JZSQ
Normal Shock Relations
https://goo.gl/E5Lwac
REFERENCES
► Notes by Matt MacLean
► Modern Compressible Flow, Anderson
► Elements of Gasdynamics, Liepmann and Roshko
► Gas Dynamics, Zucrow and Hoffman
THUMBNAIL IMAGE
By NASA (http://mix.msfc.nasa.gov/abstracts.php?p=2388) [Public domain], via Wikimedia Commons")
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Explained: Pitch Stiffness [Flight Dynamics]")
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Static text fields can be used to indicate the status of your program, or simply to write text or numbers. This video describes how to set the static text field in a MATLAB GUI.")
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This is the eighth 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 radio button for showing the camber line of the airfoil. We also code the Exit button.
Radio Button Video:
https://goo.gl/E4Owva
Exit Button Video:
https://goo.gl/aarwmW
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")
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This video explains how to select files from a folder and make those file names visible in a listbox.")
