At 5:25 you show the logos of aerospace plane hypersonic flight companies. It is notable that you did not include Reaction Engines Limited in your list of hypersonic space plane companies. Do you not consider Skylon a hypersonic platform because it's only targeting Mach 5 (a semi-arbitrary boundary)? Did you not include it because it's basically a normal turbojet after its pre-cooler, and thus not a ramjet/scramjet (what does it matter HOW the hypersonic air-breathing velocity is reached?)? Or do you not consider it a real player (Skylon related news has been sparse on the ground of late)?
These types of materials are amazing!!! I would love to see how advanced humans are in a 100 years from now...let alone 10,000 years from now ( just finished watching bothe Dune 1 and 2).... I wonder if we will be even remotely close to being that advanced with technology??????
The speed of sound does NOT change with altitude, as is so often reported in the popular press. It is a function of temperature to within about 4 decimal points. Also hypersonic is defined as the speed at which the chemistry of the air starts to change as a result of the object passing through it. That speed happens to be about mach 5.
Thanks :-) ... It changes with composition of gases AND with Temperature so, if we are going to be technical. both of those change with altitude... so... isn't the statement still roughly correct?
@@terranspaceacademy No. Certainly at one bar and below air is an ideal gas. Even if it were CO2 or CH4, the speed of sound at a specific temperature is the same as air and independent of pressure. Of course the composition of air changes mainly with humidity. But the speed of sound is influenced about three orders of magnitude more by temperature than pressure or humidity.
It is half true. It is also what the popular press presents. But it very misleading. The strongest factor influencing the speed of sound by three orders of magnitude is temperature. Since your intent is to educate, and you, in my opinion do it very well, why mislead your students by omitting the dominant factor -- temperature?
Matallic hydrogen will be incredibly useful for air breathing SSTO designs. Not only for energy density, but fuel expansion from chamber cooling could easily outflow turbo pumps.
I've looked and I have never been able to find any designs, even back of the napkin type stuff for a working metallic hydrogen engine. It's been a few months since I looked so maybe that's changed. But It's just so energy dense in its pure form that it vaporizes anything you put it in contact with inside an engine. The closest thing I've seen involved diluting the MH in some kind of solvent and just getting less performance. I don't think you can just fill a tank with it and pump it like typical rocket fuels. I'm not sure we even know what form it would be in (liquid or solid) if it is in fact metastable. I'm not sure that we know for sure that it is metastable. This problem seems to pop up with every game changing technology that may be on the horizon. It's super energetic so great power and efficiency but it eats everything you put near it. Even Anti Matter. If we discovered tomorrow that we could easily manufacture Anti Matter we still don't know how to direct it's energy without requiring so much shielding and reflecting mass as to make it impractical for anything with humans on it. I'm sure we'll figure out how to move into the Solar System and do work valuable to our species if we last long enough. But I don't think anyone knows what that will look like yet. Nuclear technologies can already get us most of the way there. But unfortunately stupidity is contagious. I wonder how these antinuclear everything folks feel when they get cancer and need a radiotherapy machine? Do they scream "No Nukes in Hospitals!" and just go die? Somehow I doubt it. I think they don't really care about the truth, they just like their community of like minded friends. Like most of the problems humans create for ourselves. Stupid, arrogant Humans are a real danger to all of our futures. They think they're geniuses and can just nuh uhhh to anything they don't understand. And failing politicians take advantage of this ignorance. No matter how beneficial for them and all of us it might be. I live in Florida and remember the Casini Launch well. The level of stupidity on display everywhere except NASA itself was eye opening.
@@allineedis1mike81 That was a massive comment so will be responding to points versus the entirety. To my knowledge metallic hydrogen has only temporarily been produced between diamond anvils under enormous pressure. It does not destroy material as antimatter does, but does pass through some elements. Which do to the high pressure can cause damage. While it would be preferable for MH to be a semi-liquid like mercury. A solid can still be injected as pellets, wire, or bar. As to use in a engine cryogenic MH would either directly cool the engine or engine coolant in a heat exchanger. Transitioning into liquid hydrogen or superheated hydrogen as the rapid temperature increase the Coulumb force severing the shared electron bonds in metallic hydrogen. That is highly theoretical as no MH currently exist to run practical experiments on, but continuing. SSTO will require a multi-stage engine with turbofan, scramjet, liquid fueled rocket stages. In the inline design I am working on the turbofan would be fueled by liquid hydrogen from a large drop tank. As the first stage to high altitude at mach3. Followed by rocket engine burn on remaining liquid hydrogen & internal liquid oxygen to Mach4.5. MH conversion to superheated high pressure hydrogen is begun scramjet is started, & lifting body drop tank is ejected to glide back for landing & reuse. Scramjet stage accelerates SSTO up to Mach15 climbing to the edge of the atmosphere. Rocket stage using a different design of heat exchanger producing liquid hydrogen & stored liquid oxygen boosts to LEO. Before a magnetic MH plasma engine powered by solar or fusion using a variable EM nozzle takes over for spaceflight. Still significant work to be done. But currently looking to be the most efficient path to space with the largest payload & safety factor. At least until technology such as direct matter to energy conversion or antimatter becomes possible. Nuclear is incredibly important to humanities future. In my opinion fission is not viable for single stage to orbit spacecraft. Reactor size/weight with required system is simply too large. Radiation shielding alone could double the weight of internal structure. unless efficient energy shield technology becomes available. Nuclear powered mach 1 bombers where attempted but failed in the cold war. A SSTO would require 50 times more power from a smaller reactor. In orbit automated freight transport is the use case for fission. Your point are valid and well taken. Cheers
@@allineedis1mike81, I’ll drink to that! The bit you said in the latter part of your comment makes me think of flat earthers lol. Well that is except for the bit about the politicians taking hold of the debate. Though with the way we seem to be more and more turning the movie Idocracy into a prophetic piece, I do tend to wonder if they just may…🤔🙄
I am constantly impressed by the quality of your videos. The technical depth and accompanying visuals are top notch in every single video. . One topic you might consider in order to capture a wider audience is some everyday common item we use and take for granted that came about due to space technology development.
Used a lot of SiC when I was still working. You can do amazing stuff with it. We used it as a ‘wall flow’ filter. Add a platinum ‘soak’ and you have a catalytic diesel filter. Put a burner in front and don’t use platinum, you have an active system. The temperatures are pretty wild, close to 2000c at times with the SiC variant we used.
Joseph, the reason Hermeus can get decent performance from their ramjet engine @ mach 5 is because they have their own proprietary pre-cooler. Ergo the hot air bypassing the turbine can be actively cooled/densified to where you can burn fuel in it and still get a decent expansion of the fluid moving through the engine. Kevin Hambsch
@@terranspaceacademy like Skylon only it's not a true LACE engine...but it cools it enought to where the ambient fuid flowing through the "ram burner" will expand adequately (w burning fuel) that you get a nozzle velocity > M5
Very complex process and amazing amount of trial and error (?) to find the material mix that works. How do these projects compare to something like Hermeus or the test vehicles launched by StratoLauncher?
@@terranspaceacademy I read about it in college , back in the 80s. It might not have gone anywhere, but it was interesting: sort of a combustion chamber formed by shock waves and fuel squired from the back of the vehicle to be burned.
how to keep hydrogen liquid while inconel melts cmc is needed but ammonia liquifies much closer to room temperature than dihydrogen that led to scott crossfield and the other pilot's success in reaching m6.72 🚀✈️
I am totally OK with AI and Robots taking the jobs of making these new high temp super materials..... Watching those old NASA videos with engineers manually filling the honeycomb structure in heat shields with a caulking gun (excuse me, a space caulking gun) makes my hands hurt. This stuff makes my hands and brain hurt.
You have likely already thought of this, but I want to encourage you anyway. I hope you will find other teachers, experts and patrons of progress you can team up with to create a well rounded school of aerospace technology. Maybe eventually create hands on fabrication and development facilities. I hope many will be inspired by your videos to pursue careers and/or investment in our reach for space.
An outstanding showcase of cutting edge technology! Material science is a truly fascinating subject! Thanks for another excellent lesson!
Thank you very much James!
Great video! Cutting edge materials fascinates me.
Glad you enjoyed it Chad!
I have a neat item of clothing made made out of alumina ceramic and high molecular weight polyethylene. Very tough stuff
Really! Where can you buy something like that?
At 5:25 you show the logos of aerospace plane hypersonic flight companies. It is notable that you did not include Reaction Engines Limited in your list of hypersonic space plane companies. Do you not consider Skylon a hypersonic platform because it's only targeting Mach 5 (a semi-arbitrary boundary)? Did you not include it because it's basically a normal turbojet after its pre-cooler, and thus not a ramjet/scramjet (what does it matter HOW the hypersonic air-breathing velocity is reached?)? Or do you not consider it a real player (Skylon related news has been sparse on the ground of late)?
I don't see them actively working on a flight platform right now. They seem to be engine only.
CSC's seem like a system that could change many fields not just high speed flight. That is so cool and deserves some deeper research on my part.
It is amazing! I'm thinking spacesuit shells also...
These types of materials are amazing!!! I would love to see how advanced humans are in a 100 years from now...let alone 10,000 years from now ( just finished watching bothe Dune 1 and 2)....
I wonder if we will be even remotely close to being that advanced with technology??????
10k out tech will be indistinguishable from magic :-)
An inspiration. Best of luck.
Thank you!
The speed of sound does NOT change with altitude, as is so often reported in the popular press. It is a function of temperature to within about 4 decimal points. Also hypersonic is defined as the speed at which the chemistry of the air starts to change as a result of the object passing through it. That speed happens to be about mach 5.
Thanks :-) ... It changes with composition of gases AND with Temperature so, if we are going to be technical. both of those change with altitude... so... isn't the statement still roughly correct?
@@terranspaceacademy No. Certainly at one bar and below air is an ideal gas. Even if it were CO2 or CH4, the speed of sound at a specific temperature is the same as air and independent of pressure. Of course the composition of air changes mainly with humidity. But the speed of sound is influenced about three orders of magnitude more by temperature than pressure or humidity.
It is half true. It is also what the popular press presents. But it very misleading. The strongest factor influencing the speed of sound by three orders of magnitude is temperature. Since your intent is to educate, and you, in my opinion do it very well, why mislead your students by omitting the dominant factor -- temperature?
Matallic hydrogen will be incredibly useful for air breathing SSTO designs. Not only for energy density, but fuel expansion from chamber cooling could easily outflow turbo pumps.
I've looked and I have never been able to find any designs, even back of the napkin type stuff for a working metallic hydrogen engine. It's been a few months since I looked so maybe that's changed. But It's just so energy dense in its pure form that it vaporizes anything you put it in contact with inside an engine. The closest thing I've seen involved diluting the MH in some kind of solvent and just getting less performance. I don't think you can just fill a tank with it and pump it like typical rocket fuels. I'm not sure we even know what form it would be in (liquid or solid) if it is in fact metastable. I'm not sure that we know for sure that it is metastable. This problem seems to pop up with every game changing technology that may be on the horizon. It's super energetic so great power and efficiency but it eats everything you put near it. Even Anti Matter. If we discovered tomorrow that we could easily manufacture Anti Matter we still don't know how to direct it's energy without requiring so much shielding and reflecting mass as to make it impractical for anything with humans on it. I'm sure we'll figure out how to move into the Solar System and do work valuable to our species if we last long enough. But I don't think anyone knows what that will look like yet. Nuclear technologies can already get us most of the way there. But unfortunately stupidity is contagious. I wonder how these antinuclear everything folks feel when they get cancer and need a radiotherapy machine? Do they scream "No Nukes in Hospitals!" and just go die? Somehow I doubt it. I think they don't really care about the truth, they just like their community of like minded friends. Like most of the problems humans create for ourselves. Stupid, arrogant Humans are a real danger to all of our futures. They think they're geniuses and can just nuh uhhh to anything they don't understand. And failing politicians take advantage of this ignorance. No matter how beneficial for them and all of us it might be. I live in Florida and remember the Casini Launch well. The level of stupidity on display everywhere except NASA itself was eye opening.
@@allineedis1mike81 That was a massive comment so will be responding to points versus the entirety. To my knowledge metallic hydrogen has only temporarily been produced between diamond anvils under enormous pressure. It does not destroy material as antimatter does, but does pass through some elements. Which do to the high pressure can cause damage. While it would be preferable for MH to be a semi-liquid like mercury. A solid can still be injected as pellets, wire, or bar. As to use in a engine cryogenic MH would either directly cool the engine or engine coolant in a heat exchanger. Transitioning into liquid hydrogen or superheated hydrogen as the rapid temperature increase the Coulumb force severing the shared electron bonds in metallic hydrogen. That is highly theoretical as no MH currently exist to run practical experiments on, but continuing. SSTO will require a multi-stage engine with turbofan, scramjet, liquid fueled rocket stages. In the inline design I am working on the turbofan would be fueled by liquid hydrogen from a large drop tank. As the first stage to high altitude at mach3. Followed by rocket engine burn on remaining liquid hydrogen & internal liquid oxygen to Mach4.5. MH conversion to superheated high pressure hydrogen is begun scramjet is started, & lifting body drop tank is ejected to glide back for landing & reuse. Scramjet stage accelerates SSTO up to Mach15 climbing to the edge of the atmosphere. Rocket stage using a different design of heat exchanger producing liquid hydrogen & stored liquid oxygen boosts to LEO. Before a magnetic MH plasma engine powered by solar or fusion using a variable EM nozzle takes over for spaceflight. Still significant work to be done. But currently looking to be the most efficient path to space with the largest payload & safety factor. At least until technology such as direct matter to energy conversion or antimatter becomes possible. Nuclear is incredibly important to humanities future. In my opinion fission is not viable for single stage to orbit spacecraft. Reactor size/weight with required system is simply too large. Radiation shielding alone could double the weight of internal structure. unless efficient energy shield technology becomes available. Nuclear powered mach 1 bombers where attempted but failed in the cold war. A SSTO would require 50 times more power from a smaller reactor. In orbit automated freight transport is the use case for fission. Your point are valid and well taken. Cheers
@@allineedis1mike81, I’ll drink to that! The bit you said in the latter part of your comment makes me think of flat earthers lol. Well that is except for the bit about the politicians taking hold of the debate. Though with the way we seem to be more and more turning the movie Idocracy into a prophetic piece, I do tend to wonder if they just may…🤔🙄
They'll need some seriously strong tanks to hold the metallic hydrogen :-)
Pete Knight, and shows photo of Mike Adams
I think that X-15 picture is of Mike Adams.
I believe so...
I am constantly impressed by the quality of your videos. The technical depth and accompanying visuals are top notch in every single video. . One topic you might consider in order to capture a wider audience is some everyday common item we use and take for granted that came about due to space technology development.
Thank you so much!
Used a lot of SiC when I was still working. You can do amazing stuff with it. We used it as a ‘wall flow’ filter.
Add a platinum ‘soak’ and you have a catalytic diesel filter. Put a burner in front and don’t use platinum, you have an active system.
The temperatures are pretty wild, close to 2000c at times with the SiC variant we used.
I'm wondering about using GRX-810 for a high temperature ultra efficient molten carbon fuel cell for LNG...
@@terranspaceacademy
I’d love to see that.
Joseph, Hermeus doesn't have a scram jet. They have a fully transitioning turbo to ram jet engine.
Is it just a ramjet? (Just checked) You are correct my friend... Chimera is NOT a Scramjet! Thank you!!!
@@terranspaceacademy You and Chi are #1 in my book. Kevin
Joseph, the reason Hermeus can get decent performance from their ramjet engine @ mach 5 is because they have their own proprietary pre-cooler. Ergo the hot air bypassing the turbine can be actively cooled/densified to where you can burn fuel in it and still get a decent expansion of the fluid moving through the engine.
Kevin Hambsch
Very cool. Reaction Engines waited too long I guess...
@@terranspaceacademy like Skylon only it's not a true LACE engine...but it cools it enought to where the ambient fuid flowing through the "ram burner" will expand adequately (w burning fuel) that you get a nozzle velocity > M5
Very complex process and amazing amount of trial and error (?) to find the material mix that works. How do these projects compare to something like Hermeus or the test vehicles launched by StratoLauncher?
These materials are much more advanced from what I can find... But the others play it close to the vest.
Does anyone else recall a concept called external burning?
Hmmm.... I don't think I have.
@@terranspaceacademy I read about it in college , back in the 80s.
It might not have gone anywhere, but it was interesting: sort of a combustion chamber formed by shock waves and fuel squired from the back of the vehicle to be burned.
how to keep hydrogen liquid while inconel melts cmc is needed but ammonia liquifies much closer to room temperature than dihydrogen that led to scott crossfield and the other pilot's success in reaching m6.72 🚀✈️
That makes sense. And ammonia is a fine fuel...
I am totally OK with AI and Robots taking the jobs of making these new high temp super materials..... Watching those old NASA videos with engineers manually filling the honeycomb structure in heat shields with a caulking gun (excuse me, a space caulking gun) makes my hands hurt. This stuff makes my hands and brain hurt.
Robots will do all of that I'm sure...
They will help us do amazing things!
👍👍👍
You have likely already thought of this, but I want to encourage you anyway. I hope you will find other teachers, experts and patrons of progress you can team up with to create a well rounded school of aerospace technology. Maybe eventually create hands on fabrication and development facilities. I hope many will be inspired by your videos to pursue careers and/or investment in our reach for space.
We would love to develop a "Trade School to the Stars! :-)
How about: “Thanks for listening and stay brave and free”😊
I like it! (but that would imply that we our freedom might be at risk and if I do that they'll come haul me away :-)
❤😢 Space planes capable of flying us to the moon.😊
It's coming! (Someday)