Warning: Some posts on this platform may contain adult material intended for mature audiences only. Viewer discretion is advised. By clicking ‘Continue’, you confirm that you are 18 years or older and consent to viewing explicit content.
The bell is scaled to match thrust though. If you get too much expansion the flow peels away from the inside of the bell and you get turbulence, pressure variations and then usually a big kerboom, especially on startup as you’re trying to ramp up to steady state conditions. I’m guessing the bell is more high-altitude optimised than true vacuum optimised.
I suspect they have so much thrust that the sea level pressure simply is irrelevant.
The bell is scaled to match thrust though. If you get too much expansion the flow peels away from the inside of the bell and you get turbulence, pressure variations and then usually a big kerboom, especially on startup as you’re trying to ramp up to steady state conditions. I’m guessing the bell is more high-altitude optimised than true vacuum optimised.