Explained: Converging-Diverging Nozzle

Why do rocket engines look the way they do? In this video, I'll be explaining what a converging-diverging (CD) nozzle is, and how the flow changes as it passes through it. See the Relevant Videos section below for some more in-depth videos on each of the flow states, including examples! ================= ===== NOTES ===== ================= ► At 11:28, I say "so far, we have subsonic flow throughout the nozzle for all these cases." I meant to say that we have isentropic flow throughout the nozzle for all these cases. ========================== ===== RELEVANT VIDEOS ===== ========================== Pressure Ratio Delineations https://goo.gl/VQnH1n Normal Shock in the Nozzle Calculations https://www.youtube.com/watch?v=b0wvwkKqoVw Overexpanded Flow Calculations Coming soon! Underexpanded Flow Calculations Coming soon! Area-Mach Number Relation https://goo.gl/j4FwQX Sonic State (Critical, Star) https://goo.gl/vhjESy Normal Shock Relations https://goo.gl/bhw6Ln Isentropic Relations https://goo.gl/mkdNHd Stagnation Relations https://goo.gl/hBY2AV ============================== ===== RELEVANT BLOG POST ===== ============================== http://www.joshtheengineer.com/2016/11/16/solving-the-area-mach-number-relation/ ====================== ===== REFERENCES ===== ====================== ► Notes by Matt MacLean ► Modern Compressible Flow, Anderson Amazon Link: https://goo.gl/9B7F8H ► Elements of Gasdynamics, Liepmann and Roshko Amazon Link: https://goo.gl/brfScu ► Gas Dynamics, Zucrow and Hoffman Amazon Link: https://goo.gl/mwLk8L =========================== ===== THUMBNAIL IMAGE ===== =========================== By NASA (NIX #: MSFC-0201422. [1], Alt. URL.) [Public domain], via Wikimedia Commons