this post was submitted on 13 Dec 2024
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[–] [email protected] 0 points 1 week ago (1 children)

@yogthos I did.

Scramjets are fundamentally fighting Newton’s 3rd law. Slow air down by Mach 5 only to speed if back up to Mach 5 again. You’re burning tonnes of fuel to accomplish almost nothing.

If they have a practical scramjet vehicle (they don’t), then they should feel free to show the world, rather than posting vacuous bullshit on the Internet.

[–] [email protected] 2 points 1 week ago (1 children)

Nowhere in the paper does it say that this is a scramjet. Meanwhile, obvious solution for a hypersonic vehicle would be to go to upper atmosphere at a lower speed, and then achieve speeds over Mach 5 where there is low atmospheric density. You really think that you're smarter than literally everybody working on this project, and it's absolutely hilarious.

Maybe take your own advice and stop posting vacuous bullshit on the internet pretending that you're an expert on things you have little understanding of.

[–] [email protected] 1 points 1 week ago (2 children)

@yogthos “The paper”.

This isn’t a paper. It’s a blog post.

It’s no more a “paper” that is subject to any kind of scientific debate than some rando who said they made cold fusion in their microwave.

“Jumbo jet prototype”. Bless.

[–] [email protected] 3 points 1 week ago* (last edited 1 week ago)

The "paper" that OP is referring to is the one they posted a few levels up. It links to a researchgate paper that I believe is associated with the article. Just from a quick look at the paper, which is only 3 pages, they are talking about the design the aircraft uses to mitigate the negative effects that occur at hypersonic speeds. They refer to the Waverider design and modified it by including a High-Pressure Capturing Wing to improve lift. Waveriders are designed to conform to the shockwaves the vehicle produces at hypersonic speeds to reduce the drag from those shockwaves. When designing high speed aircraft you have to design around the shockwaves it will produce. This enhancement seems to improve the lift the vehicle creates at those speeds.

Also you aren't getting everything right in your arguments. Earlier you stated that scramjets are fighting Newton's 3rd law which states, "For every action, there is an equal and opposite reaction". You do understand that all air-breathing engines slows the air down before it gets to the engine. This is usually done during a compression cycle to increase the pressure and density of the air. Turbojet and Turbofan engines do this using compression fans, Ramjets uses a normal shockwave, and scramjets uses a series of oblique shockwaves called a "shock train". The difference between a scramjet and the other engines is the airflow is subsonic in Turbojet, Turbofan, Ramjet, etc while the air enters the engine at supersonic speeds for scramjets. That's why its called a SCRamjet, Supersonic Combustion Ramjet. But like OP said the paper doesn't mention what type of engine was used, only that it was a hypersonic vehicle so it could be a rocket.

How do I understand this? I actually have a degree in aerospace engineering, I've worked on scramjets (X-51) for the USAF, and I designed engines for GE Aviation. Your arguments are all wrong.

[–] [email protected] 2 points 1 week ago

Nothing more adorable than internet randos acting like they're bonafied rocket scientists. Bless.