It is also weird to see the use of the measurement units of the Roman Empire. After the loss of the Mars lander due to confusion about the thrust of a rocket motor ( thrust in Newton or lbf ) the old units should have been banished altogether.
Chinese Hypersonic Developments (HGVs/HCMs)
- Thread starter A.Man
- Start date
AssassinsMace
Lieutenant General
Where's all the hypersonic military and civilian aircraft in use today if Western nations have all the information they need from back in 60s and 70s?
Classified
TerraN_EmpirE
Tyrant King
Oh for goodness sake. Seriously I just supplied you guys with a list of shock tunnels that can simulate up to Mach 30!
And really even super sonic aircraft never bridged into commercial aviation.
And Delft some industries in the US use metric others use English units yes there was a conversion issue but that was corrected for space program use.
And as to the failing of the US program we only know that part that was released to the public.
And really even super sonic aircraft never bridged into commercial aviation.
And Delft some industries in the US use metric others use English units yes there was a conversion issue but that was corrected for space program use.
And as to the failing of the US program we only know that part that was released to the public.
Pretty much. The biggest challenge for deploying technology has never been capability, but economics.
The Chinese were using the new large diameter Mach 9 wind tunnel to test the actual firing of a real hypersonic test engine. Which is why they mentioned the need for the test duration to last at least 100ms to see if there is flame out problems and other issues with the engine under the actual speeds that they were supposed to work at.
Simulation software may not predict accurately all aerodynamic behaviour at these speeds, and I don't think at the current stage they can actually simulate how well an actual hypersonic engine would work*, not just passive flow. Also simulation is not that good for predicting turbulence flows.
*but just maybe, after much real world tests, they can begin to incorporate some design rules into the simulation software
Then I hope someone do not just say "see, you don't need wind tunnels when you can ALREADY do all that in simulation".
Simulation software may not predict accurately all aerodynamic behaviour at these speeds, and I don't think at the current stage they can actually simulate how well an actual hypersonic engine would work*, not just passive flow. Also simulation is not that good for predicting turbulence flows.
*but just maybe, after much real world tests, they can begin to incorporate some design rules into the simulation software
Then I hope someone do not just say "see, you don't need wind tunnels when you can ALREADY do all that in simulation".The problem with that someone's line of thinking is whether theory (input to the computer program) comes from day dream or from real world. It is not an issue of physical science, but a philosophy one. I suggest someone to read Materialism (philosophy).
And actually, do you really think nations share their most advanced aerodynamic simulation software? Software that they build up painstakingly using real wind tunnel data? Yeah a nation may not need to do some task with the wind tunnel when they can use prediction in software, provided that they already have done the work and understood the problem thoroughly.
But a country with no advanced wind tunnel testing experience arguing that they can do it all in software? Good luck, and where is your software?
But a country with no advanced wind tunnel testing experience arguing that they can do it all in software? Good luck, and where is your software?
Indeed, those data are more important than a real aircraft.
I'm aware that in US the automotive industries converted much earlier to metric measurements than aerospace. Some time ago there was the joke that all countries had converted except US and Yemen.