How Shock Waves Affect a Rocket Engine - Over & Under-Expanded Nozzles

[@funkyzedrox]

You've just helped a Physicist with her dissertation :D thank you, very well explained

[@colinburfeind6947]

Just found your channel today and I’m really liking your videos. I’m a high schooler so some of the math goes above my head but that’s why I’m here to grasp it more over time. Thank you!

[@amjadalipasha8380]

Thanks. It gives good info with schematic sketches of the flowfield.

[@dimitridovgan6364]

Thank you very much for the great video! Just one thing - the audio quality could be better. Its a little bit hard to listen. Thanks!

[@VDEngineering]

I'm saving up money for a microphone. Thanks for the feedback tho!

[@bill4639]

@@VDEngineering Just move the mic further away from your mouth and put more foam over it

[@usaf1983]

You are awesome man. I am struggling for my finals and this has been extremely helpful. Thank you

[@marionherring1045]

Thank you for your time and dedication!

[@didarulhasansaharaj4396]

Your videos are so educative. I'd love if you upload videos about Prandtl Meyer Function and method of characteristics and how these are used for designing nozzle.

[@VDEngineering]

kzbin.info/www/bejne/jXvOhXqlnMSUgZIfeature=shared

[@steffenleo5997]

Good Day sir, on your video 6:58 on right top there is a diagram.Any details can you tell about this diagram, y-axis and x-axis also the several line in this graph... Great videos thanks a lot... 👍👍

[@mohammadtaleghani5973]

Thanks for the amazing videos! If an under-expanded nozzle is more efficient, then why in jet engines with afterburners we see an over-expanded nozzle?

[@jamesquinn6662]

I have a few questions about your MoC code. Why is your left running characteristic a negative of your right running characteristic? That would imply the shock is reflected at the same angle of incidence as a right running characteristic. Does it not reflect anlong the centre line by the mach angle ?

[@Krzeszny95]

Thank you for the video. Where is the 6:15 chart from? Your face covered the ISP and I wanted to share that chart with KSP modders. Knowing that nozzle underexpansion is better than overexpansion would be important in modelling fictional rocket engines.

[@steffenleo5997]

Any formula you mentioned in these video about how to calculate the length of nozzle, so later on we now where this nozzle is underexpansion or overexpansion or optimum expansion?.... Thanks.. 👍

[@ad2181]

Thank you for an excellent explanation.

[@dominiclanza2368]

I really appreciate your lessons. Very well done. Thank you

[@justindavid2333]

Thank you for this great video! I am grateful that I found your channel, especially about aerodynamics and control theory. Can't wait to watch them.

[@aavkashyaan7187]

Hello,it'z very interesting video.really very help full.but can you give me reason of why the underexpansion nozzel are generally used? Give basic detail of both difference

[@StefanHRX]

Why cant the shockwaves cross the centerline with the overexpanded nozzle? And ehich physics law would be broken If the flow Changes direction in one step? Thanks in advance!

[@makantahi3731]

so in throat is Ma=1, at what temperature, what gives what gas speed in km/h

[@IstyManame]

You mentioned that oblique shockwaves are forming at the nozzle because fuel pressure is "trying" to reach an equilibrium with the outside pressure, but then why are oblique shockwaves are forming in an underexpanded case? I definitely got something wrong, I'm not an engineer, I'm a VFX artist trying to understand how the mach diamond pattern is formed

[@antd8667]

Looking for effective velocity using Argon throat. .020 inch tank pressure 60,000 psi . flow rare at nozzle and mass loss rate And trust at ambient pressure

[@Gold3nAng3l]

Congratulations on getting into a Masters program! What university are you going to study at? (Only if you're comfortable saying where of course) I'm working on my masters degree right now and should graduate next Spring! Great video and keep up the good work!

[@parvathykrishna3898]

Thank you❤️

[@RaviTeja-fx7ob]

please do a video with a simulation on this concept by mentioning backpressure

[@jagrutbrahmbhatt733]

What are your qualifications, sir? You are amazing

[@kakashisharigan336]

God sent this guy

[@cristianrivas2870]

Great! thanks

[@fusion5329]

I'm confused of why the engine has higher isp with underexpansion than overexpansion it makes sense because a part of the thrust formula is (pressure exit - pressure ambient) but why don't you make the nozzle as underexpanded as possible?? It will still have the same mass flow rate but the thrust will be higher according to the thrust formula?? What is the point of optimizing lenght of nozzle? Why not make it as under expanded as possible. Mass flow rate * Exhaust Velocity + (Pressure Exit - Pressure Ambient) * Exit Area. So according to that formula the thrust should increase when underexpansion occurs?? I hope you understand my question thank you sir.

[@pruthviutturwar49]

The main purpose of the nozzle is to get high velocity exhaust, the term (Pressure Exit - Pressure Ambient) * Exit Area in the formula is approximate because it never delivers the thrust calculated from this terms but lesser. You see the flow out of the under expanded nozzle is not directed opposite of the rocket motion but away from it as it expands outside the the nozzle, so the energy carried by the perpendicular component of velocity does not provide thrust to the rocket. hence our purpose will be to direct the large mass flow opposite to the rocket motion. So basically we have to achieve the balance between the losses due to underexpansion and losses due to overexpansion( shock formation ).

[@Flyingwithus]

Really nice explanation!! Keep up the good work. Can you make videos about the combustion chamber and turbines? It will really be helpful. Thanks :)

[@nurzhannurbek148]

can you help me to modeling a rocket engine, please?

[@VDEngineering]

kzbin.info/www/bejne/n4PYeJKQl99lf8k

[@aavkashyaan7187]

You work on which engine? Solid propellent or liquid propellent?

[@nurzhannurbek148]

@@aavkashyaan7187 it is a liquid fuel but it is more similar in size to a spatial orientation engine

[@aavkashyaan7187]

@@nurzhannurbek148 because I am working on solid fuel rocket motor🤗

[@nurzhannurbek148]

@@aavkashyaan7187 wow, where are you working?

[@halamkajohn]

computer question? how to make a Commodore computer / make a command GOSUB ans. loop in read only memory. Dont get stuck with microsoft.

[@rookiebird9382]

Your channel is so under viewed

[@halaal-khafaji7880]

thanks

[@spb1179]

Where are you going to college?

[@VDEngineering]

Canada

[@PriyabrataPradhanSipun]

thanks vai

[@mareksarvas1102]

thx

[@saddamgillani7608]

can i get your email or something like that to contact you if you dont mind

[@CatboyChemicalSociety]

lel I was also thinking that Mach diamonds look like inneficiency!!

[@maazshariff9309]

graph from rocket propulsion elements

[@RahulYadav-vs2bt]

hello sir , Rahul this side from aerospace engineering, I really need your help sir , please please please give me linkedln or fb or insta or mail anything so that I can contact you for my final year project , please sir

[@dr.lexwinter8604]

Thank you for holding your lav mic and shouting into it. I almost thought this was going to be a decent video.