Instead of trying to achieve supersonic inlet conditions with an EDF (quite challenging) you can use a compressed air supply. With a pressure ratio of slightly above 1.8 and a small enough choke (or high enough flow rate) you can get sonic velocities. A large compressor is cheaper than a moderate sized EDF so I believe this is fairly economical as well.
I suppose you could also add high subsonic pressurized air before the fan in a sealed tube. Might simulate high speed flight. edit: probably wouldn't work super well as a high speed analogue. still a fun test.
I don't think the ideal compressor for the "EDF afterburner" application/concept is being manufactured (yet?). It really needs a multi-stage axial aluminum, titanium or carbon fiber compressor to reach the pressure ratio for supersonic expansion with an acceptable thrust to weight ratio, also probably a longer flame tube for more efficient/complete combustion.
Hi, love this. Using Furnace Cement on CF -great idea! Even to duplicate jet engine compression ratios would take 3 or 4 stages of alternating rotating EDFs. You might be able to use a centrifugal compressor on the inlet -there's a reason why Frank Whittles engines had a centrifugal compressor 1st stage. I think it highly unlikely you can achieve hypersonic compression ratios without a vastly more expensive setup.
It's nice to see someone not melting down their engine every test. I think you could get more thrust if the diameters of the inner and outer casings are closer. Like putting your thumb on a garden hose...bernoulli's principle!
love the video, I would recommend switching to a compressor fan instead of the EDF's. It might turn out closer to a turbojet (because of the compressor, But I think that high pressure air is always favorable over high speed air (especially when it comes to ignition).
You would get stronger parts and more precise geometry, and therefore better aerodynamics inside your engine if you filament wind on 3D printed mandrels. You can remove the mandrels by baking in an oven to let the molten plastic flow out.
90k rpm can be achieved with some BLDC motors i think, you can even wind your own and use maybe a less permissive core material, like 15 percent ferrite PLA (if you do you will need to make a decent driver circuit from scratch for the required voltage to get it up to that speed cause i doubt those themselves are made either) as for the impeller, you could adapt the geometry to fit in an impeller from a used up car turbo ( gonna be a pain to get the right dimensions without the fin profile measures from paper tho) and while youre at it change the inside geometry to make a second air intake like a venturi pump, so it makes an air vortex that cools the inner walls and generates "suction" forwards while its at it. if you want it to run on fuel only, theres some recent vids on a trick the navy used for better performance on their jets, basically split the compressor axis (one inside another) to different stages, so the outwards one was being driven by the higher speed outlet stage gas while the inwards one was driven by the high pressure combustion stage gas.
Notice how the burner keeps blowing out? You might need to add a flame holder to prevent that. It would also increase combustion chamber pressure. A simple steel baffle plate or peforated cylinder would do. Just get a stainless steel dishwasher silverware holder or soap holder from Walmart or wherever and drill a few holes in it to start with, test fire it and add more holes as needed until it works right.
So Cool. I think that in this type of design the combustion should happen inside of the shielding of the EDF airflow. The envionment air is static. The EDF flow is second fastest. The hot combustion should be fastest and inside the velocity wall of the EDF fan. This requires two air flows. One for the EDF and a second for the Hot ICE combustion. I love what you are doing. Keep Going. Thrust is about mass air flow. On a small diameter that means very high velocity.
Yeah definitely use a ducted centrifugal impeller instead of propeller like in the edf. I bet you can just 3d print an impeller and a diffuser for your edf motor
If you want to create sustained air pressure, add multiple large fan intakes and funnel it into a smaller space to increase the pressure as with wind tunnels. If you can't create bigger intakes, then I would focus on miniaturizing the ramjet components as its ratio between the amount of air being forced in versus the size of the exit opening. If you used a 24-inch industrial fan with a high CFM (>5000 CFM) you can funnel that down to a 2-inch diameter, this would increase the density by 144x, still not close to hypersonic density though. If you had nine of the 24-inch industrial fans all being channeled into 1-inch outlets, then combine the nine streams into one smaller 1-inch final exhaust outlet, this could start getting close to the density level required depending on your local ambient air pressure. However, you are also talking about over 2000 pounds per square foot of pressure so just containing this can be challenging, with even a small piece of debris becoming very damaging.
This would be an interesting setup, and I have though about doing something similar to this. The two biggest problems are cost and size, this would be very expensive to source materials and the length of the funnels would be very long to get a steady flow
@@JRYBuilds Agreed, the size and cost of materials would present a challenge. If I was to do something like this, I would look for a cheap way to source the fans first and then worry about where and how to build it later. I have heard that people affected by the Boulder fire were given large fans by the utility companies to clear out the air and the companies don't want them back so I would expect they will appear as second-hand items online soon once people are done using them. Not sure how powerful they are but free is a great price. If you know someone in the area, they may be able to collect a bunch for you for free as people will probably throw them away otherwise. Once the fans are acquired, I'd probably build it inside a farm building, like a large barn or machinery shed, as the longer you can make it, the better it will perform.
Maybe some stators past the edf and more even fuel injection could help performance. Also, perhaps this can use an EDF to get to speed but become a ramjet in the air after initiating a dive in the flight profile to get sufficient compression and use a ramjet to sustain that speed
Theoretically you could create a venturi bottle neck (make the circle smaller and guide the air into its center point) its a multiplier for the airspeed at the price of a bit of drag.
Try a wind tunnel design to increase velocity. Large diameter intake with lower fan speeds narrowed down to the ramjet intake. Basically acting like a air intake funnel only powered by a fan on the large end. I'm talking a box fan size fan with a 18" intake narrowed to 3-4". The idea is to prove the theory works and then refine is later.
It can withstand direct flame from a blowtorch, it’s very strong against heat. The part I’m worried about is the fireplace mortar which is only rated for 2000 F. I did find a new one that is rated for 3000 F which I will use in my next version
Maybe a more powerful electric motor with a sort of long multiple row fanblade setup like a jet engine compressor would work. Then just squeeze the air to a tiny area to get the most air speed. You wouldn't need supersonic fan blades if you could supply enough static pressure to use a nozzle to accelerate the air. You may have to use carbon fiber and resin to make each fan blade. You could try making a thin walled hollow 3d print then coating them in fiber and resin to make your blades. It would be a lot of work but I don't know of any lightweight compressor blades for sale as hobby stuff. You could also try a massive air compressor for testing. Maybe a bunch of progressively smaller diameter electric hobby motors/fans would work. Either way good luck and I will continue to watch your career with great interest.
I think that kevlar would be a more suited material for the exterior shell, carbon +-45 is not oriented correctly for your loads 1 Unidirectional layer as rings (90) would be needed if pressure builds up. 12K cabon filament wrap wold be ideal. The aerospike could be just mortar for testing purposes(or 3D printed ceramic). roughness on the chamber can be enough to avoid success. a refractory inner surface will be needed (often coper to dissipate heat). not sure your propeller can suck enough O2 into the chamber fast enough because Reynolds at that size, probably you need a very lengthy compressor to get the volume right (maybe the whole aircraft body?) with few compressor stages. Liquid oxidiser and/or fuel could X400 the gas volume boosting your propulsion without the propeller.. (is a rocket) liquid O2 + Liquid propane (1l bottles exist ... at 110bar)... that would launch your plane to the stratosphere... casting metal from 3Dprint is also a good approach or conforming a thin copper layer around your 3D print ...
The biggest problem with Kevlar is the melting point, which is about 930 F. If I coated the outside with Kevlar to give the engine strength the heat should dissipate enough to not ruin the structural integrity of the Kevlar. The other problem is cost, Kevlar is not very cheap compared to carbon fiber
Suggestion? Try coating your molds in resin to help with things being conductive. Might help with your pressure issue too. Have you tried getting it started with a canister of pressurized gas? I mean for what you're doing is suggest carbon monoxide or even just carbon dioxide. The fuel:O2 mixture will still make sure it ignites and CO and CO2 will just temporarily add pressure the reaction should maintain it.
I can’t use any resin because of the high temperature. I’ve been thinking of adding compressed oxygen but that would be basically building a rocket and not an engine
@@JRYBuilds I'm honestly suggesting that instead of O2 going with compressed carbon monoxide, seriously. I've used it in done less than conventional race car engines and that's what it was used for was increasing ignition pressure... Now my guess to no where near the same as we were using methane as the primary fuel source but it's better than making rocket and the need that comes with that. If pressure is all you need have you considered nitrogen? You can buy silicone/acrylic resins at hobby lobby that can withstand upwards of 2500C, it's not perfect but to much more than that and it won't matter that much what is made out of anyway.
I was just thinking of this the other day, in the future I may try and build a version of this. It would be a great way to trim out the perfect thrust ratio
if its all staying on a platform , you could spin the impreller on a 3-1 or 4-1 gear increase from the motor ( e.g using a 25k rpm rc brushless, and a metal impeller) a planetary gear mounted direct to the bldc motor could push 90k,, but these ideas dont solve the real issues at 90k like bearings , and the impeller exploding like a grenade
Cool, but getting a model plane to mach speeds just to be able to ignite the engine is not practical. Maybe try making an hybrid jet engine and a good plane body and you might be able to get it at a stable combustion. But after all it was a really good vid.
@@JRYBuilds I just now realized that an rc jet/rocketplane over speed of sound is probably illegal everywhere and sonic booms are probably the worst thing that can happen to a normal neighborhood.
Wow awesome! I was just thinking about this stuff today and there’s a video just uploaded yesterday all about it lol! What do you think about creating a ( i don’t know the exact terms) constricting nozzle that gets tighter like you see on some jest?
@@JRYBuilds so is sodium silicate as concrete sealer, or you can make with sodium hydroxide (drain cleaner) and silica gel (crystal cat litter). ive always wondered how it would work with carbon fiber, you should do it.
Can you not create a smaller ram jet, So ypu end up with a sort of turbo jet set up, the ram jet is say 50mm reducing to 40mm to increase pressure. Yet still allowing faster moving air to bypass the ramjet also helping cool the outside. Hope that makes sence does in my head haha
Ramjet, one of the things I wanted to do at some point. I don’t remember but doesn’t a scramjet work at low speeds? (It is meant for even higher speeds) The flame looked decently stable without the spike while it was inside the housing, spinning in a small vortex (this could be a bad think, idk), but I think a increase would help at the combustion point like you said. I really like where you are going with this and hope to see more!
A ramjet combusts at subsonic speeds and a scramjet combusts at supersonic speeds, ram jets are used at subsonic speeds but are extremely inefficient below Mach 1
The flame might stable but it's a fancy blowtorch and not an engine. It's impossible to create significant thrust if the incoming air is subsonic. You need at least > Mach 1, better 2, ideally 3.
I actually agree, it technically isn’t a ramjet but it is more than just an afterburner. It just has a few similarities to a ramjet and for the sake of UA-cam it’s easier to call it a ramjet.
yes, I have seen some designs do what I did though and wanted to see what differences they would make. On a traditional ramjet there is no compressor so they use an aerospike for the compression stage.
@@JRYBuilds Okay, yeah that seems intersesting. Just started working on designing a simple jet engine myself but still working on the compressor design so I'm not close to working on the nozzle or combustor yet.
I thought about doing that, but cast metal is too heavy for a setup like this. Aluminum would deform and steel is difficult to cast for an amateur setup
Instead of trying to achieve supersonic inlet conditions with an EDF (quite challenging) you can use a compressed air supply. With a pressure ratio of slightly above 1.8 and a small enough choke (or high enough flow rate) you can get sonic velocities. A large compressor is cheaper than a moderate sized EDF so I believe this is fairly economical as well.
I concur I was typing up something along these lines when I saw your comment :)
Me too I was going to suggest something else but this sounds like a better solution
I suppose you could also add high subsonic pressurized air before the fan in a sealed tube. Might simulate high speed flight.
edit: probably wouldn't work super well as a high speed analogue. still a fun test.
Maybe instead of a fan blade, a printed centrifugal compressor would get air moving sufficiently quick
I don't think the ideal compressor for the "EDF afterburner" application/concept is being manufactured (yet?). It really needs a multi-stage axial aluminum, titanium or carbon fiber compressor to reach the pressure ratio for supersonic expansion with an acceptable thrust to weight ratio, also probably a longer flame tube for more efficient/complete combustion.
Honestly this is very impressive, its been amazing to see how much you have developed this design and I look forward to seeing where you take it next.
Thank you, it’s definitely been a learning experience
Hi, love this. Using Furnace Cement on CF -great idea!
Even to duplicate jet engine compression ratios would take 3 or 4 stages of alternating rotating EDFs. You might be able to use a centrifugal compressor on the inlet -there's a reason why Frank Whittles engines had a centrifugal compressor 1st stage. I think it highly unlikely you can achieve hypersonic compression ratios without a vastly more expensive setup.
I'm a simple man, if I read "Carbon Fiber Ramjet" I click it.
It's nice to see someone not melting down their engine every test. I think you could get more thrust if the diameters of the inner and outer casings are closer. Like putting your thumb on a garden hose...bernoulli's principle!
love the video, I would recommend switching to a compressor fan instead of the EDF's. It might turn out closer to a turbojet (because of the compressor, But I think that high pressure air is always favorable over high speed air (especially when it comes to ignition).
You would get stronger parts and more precise geometry, and therefore better aerodynamics inside your engine if you filament wind on 3D printed mandrels. You can remove the mandrels by baking in an oven to let the molten plastic flow out.
That’s kind of what I’m planning on doing next, I’ve been experimenting with a ton of different methods and materials
90k rpm can be achieved with some BLDC motors i think, you can even wind your own and use maybe a less permissive core material, like 15 percent ferrite PLA (if you do you will need to make a decent driver circuit from scratch for the required voltage to get it up to that speed cause i doubt those themselves are made either)
as for the impeller, you could adapt the geometry to fit in an impeller from a used up car turbo ( gonna be a pain to get the right dimensions without the fin profile measures from paper tho) and while youre at it change the inside geometry to make a second air intake like a venturi pump, so it makes an air vortex that cools the inner walls and generates "suction" forwards while its at it.
if you want it to run on fuel only, theres some recent vids on a trick the navy used for better performance on their jets, basically split the compressor axis (one inside another) to different stages, so the outwards one was being driven by the higher speed outlet stage gas while the inwards one was driven by the high pressure combustion stage gas.
Super cool! if i remember right, EDFs don't make too much pressure. Looking into turbo chargers might be a path towards higher pressure/speed.
That’s going to be the next video :)
For high velocity flow try a scuba tank or a paint ball tank filled with air.
From what i lmow of ramjet... U kinda need supersonic air for it to work.
A very big compressor and ear plugs maybe.
Notice how the burner keeps blowing out? You might need to add a flame holder to prevent that. It would also increase combustion chamber pressure. A simple steel baffle plate or peforated cylinder would do. Just get a stainless steel dishwasher silverware holder or soap holder from Walmart or wherever and drill a few holes in it to start with, test fire it and add more holes as needed until it works right.
That’s what I had on previous versions, I was trying something new by pumping in fuel from the outer edge.
I'm sure you have considered this but you could have a centrifugal pump for more pressure.
That’s what I’m working on right now, hopefully I’ll get a video out soon about it
So Cool. I think that in this type of design the combustion should happen inside of the shielding of the EDF airflow. The envionment air is static. The EDF flow is second fastest. The hot combustion should be fastest and inside the velocity wall of the EDF fan. This requires two air flows. One for the EDF and a second for the Hot ICE combustion. I love what you are doing. Keep Going. Thrust is about mass air flow. On a small diameter that means very high velocity.
Yeah definitely use a ducted centrifugal impeller instead of propeller like in the edf. I bet you can just 3d print an impeller and a diffuser for your edf motor
If you want to create sustained air pressure, add multiple large fan intakes and funnel it into a smaller space to increase the pressure as with wind tunnels. If you can't create bigger intakes, then I would focus on miniaturizing the ramjet components as its ratio between the amount of air being forced in versus the size of the exit opening. If you used a 24-inch industrial fan with a high CFM (>5000 CFM) you can funnel that down to a 2-inch diameter, this would increase the density by 144x, still not close to hypersonic density though. If you had nine of the 24-inch industrial fans all being channeled into 1-inch outlets, then combine the nine streams into one smaller 1-inch final exhaust outlet, this could start getting close to the density level required depending on your local ambient air pressure. However, you are also talking about over 2000 pounds per square foot of pressure so just containing this can be challenging, with even a small piece of debris becoming very damaging.
This would be an interesting setup, and I have though about doing something similar to this. The two biggest problems are cost and size, this would be very expensive to source materials and the length of the funnels would be very long to get a steady flow
@@JRYBuilds Agreed, the size and cost of materials would present a challenge. If I was to do something like this, I would look for a cheap way to source the fans first and then worry about where and how to build it later. I have heard that people affected by the Boulder fire were given large fans by the utility companies to clear out the air and the companies don't want them back so I would expect they will appear as second-hand items online soon once people are done using them. Not sure how powerful they are but free is a great price. If you know someone in the area, they may be able to collect a bunch for you for free as people will probably throw them away otherwise. Once the fans are acquired, I'd probably build it inside a farm building, like a large barn or machinery shed, as the longer you can make it, the better it will perform.
I can’t wait to see this on a plane
Flow through a ramjet engine is subsonic.
Maybe some stators past the edf and more even fuel injection could help performance. Also, perhaps this can use an EDF to get to speed but become a ramjet in the air after initiating a dive in the flight profile to get sufficient compression and use a ramjet to sustain that speed
"it's not perfect" 😆 indeed it isnt far from perfect, good video anyway
Theoretically you could create a venturi bottle neck (make the circle smaller and guide the air into its center point) its a multiplier for the airspeed at the price of a bit of drag.
The simplest thing to try next would be to fix where combustion takes place. That alone is probably going to help significantly.
Try a wind tunnel design to increase velocity. Large diameter intake with lower fan speeds narrowed down to the ramjet intake. Basically acting like a air intake funnel only powered by a fan on the large end. I'm talking a box fan size fan with a 18" intake narrowed to 3-4". The idea is to prove the theory works and then refine is later.
I did not know carbon fiber would be able to handle that much temperature
It can withstand direct flame from a blowtorch, it’s very strong against heat. The part I’m worried about is the fireplace mortar which is only rated for 2000 F. I did find a new one that is rated for 3000 F which I will use in my next version
Maybe a more powerful electric motor with a sort of long multiple row fanblade setup like a jet engine compressor would work. Then just squeeze the air to a tiny area to get the most air speed. You wouldn't need supersonic fan blades if you could supply enough static pressure to use a nozzle to accelerate the air. You may have to use carbon fiber and resin to make each fan blade. You could try making a thin walled hollow 3d print then coating them in fiber and resin to make your blades. It would be a lot of work but I don't know of any lightweight compressor blades for sale as hobby stuff. You could also try a massive air compressor for testing. Maybe a bunch of progressively smaller diameter electric hobby motors/fans would work. Either way good luck and I will continue to watch your career with great interest.
in theory you could build a compressor
Air compressor got the pressure
Good luck
maybe a turbo removed from a motor?
maybe a small jet engine would be able to achieve the required pressure for efficient combustion?
I think that kevlar would be a more suited material for the exterior shell, carbon +-45 is not oriented correctly for your loads 1 Unidirectional layer as rings (90) would be needed if pressure builds up. 12K cabon filament wrap wold be ideal. The aerospike could be just mortar for testing purposes(or 3D printed ceramic). roughness on the chamber can be enough to avoid success. a refractory inner surface will be needed (often coper to dissipate heat). not sure your propeller can suck enough O2 into the chamber fast enough because Reynolds at that size, probably you need a very lengthy compressor to get the volume right (maybe the whole aircraft body?) with few compressor stages. Liquid oxidiser and/or fuel could X400 the gas volume boosting your propulsion without the propeller.. (is a rocket) liquid O2 + Liquid propane (1l bottles exist ... at 110bar)... that would launch your plane to the stratosphere... casting metal from 3Dprint is also a good approach or conforming a thin copper layer around your 3D print ...
The biggest problem with Kevlar is the melting point, which is about 930 F. If I coated the outside with Kevlar to give the engine strength the heat should dissipate enough to not ruin the structural integrity of the Kevlar. The other problem is cost, Kevlar is not very cheap compared to carbon fiber
Suggestion? Try coating your molds in resin to help with things being conductive. Might help with your pressure issue too. Have you tried getting it started with a canister of pressurized gas? I mean for what you're doing is suggest carbon monoxide or even just carbon dioxide. The fuel:O2 mixture will still make sure it ignites and CO and CO2 will just temporarily add pressure the reaction should maintain it.
I can’t use any resin because of the high temperature. I’ve been thinking of adding compressed oxygen but that would be basically building a rocket and not an engine
@@JRYBuilds I'm honestly suggesting that instead of O2 going with compressed carbon monoxide, seriously. I've used it in done less than conventional race car engines and that's what it was used for was increasing ignition pressure... Now my guess to no where near the same as we were using methane as the primary fuel source but it's better than making rocket and the need that comes with that. If pressure is all you need have you considered nitrogen?
You can buy silicone/acrylic resins at hobby lobby that can withstand upwards of 2500C, it's not perfect but to much more than that and it won't matter that much what is made out of anyway.
Your channel reminds me of integza, great content btw, got a new sub from me
Keep updating ! im workin on something similar
Very… cool. Thanks
I’m building a rocket so this was helpful
Thanks for the pin, I will send a link to the take off. The destination is the moon titan
how much thrust in Newton
And thanks it is very great project
I’m Planning on testing that in the next video
Hey, you should add one flameholder after the fuel injection!
Maybe you want to serve pressured oxygen instead of normal air to make the ramjet useful 🤔
I wanted to do that but the purpose of this setup was to take oxygen from the atmosphere. I will most likely use pressurized oxygen in a future video
this is awesome man
amazing
Would it help to have a variable exhaust nozzle? Something simple as 2 half shells on a spring loaded hinge.
I was just thinking of this the other day, in the future I may try and build a version of this. It would be a great way to trim out the perfect thrust ratio
That is so neat!
What kind of ~thrust can this produce? Great video !
The added thrust is very minimal it’s more for effect and testing how carbon fiber holds up to high heat
if you need high pressure try to use turbine
maybe a turbo from an engine?
the edf is not actually a part of the jet engine, it is just there to simulate the high speed airflow right? becasue ramjets have no moving parts
Yes, this isn’t truly a ramjet, it’s more of an experimental hybrid
@@JRYBuilds I loved it
GOOD
if its all staying on a platform , you could spin the impreller on a 3-1 or 4-1 gear increase from the motor ( e.g using a 25k rpm rc brushless, and a metal impeller) a planetary gear mounted direct to the bldc motor could push 90k,, but these ideas dont solve the real issues at 90k like bearings , and the impeller exploding like a grenade
Cool, but getting a model plane to mach speeds just to be able to ignite the engine is not practical. Maybe try making an hybrid jet engine and a good plane body and you might be able to get it at a stable combustion. But after all it was a really good vid.
Yea it’s basically impossible, it’s more of a concept but I think I could hit over 200mph if I improve the pressure efficiency
@@JRYBuilds I just now realized that an rc jet/rocketplane over speed of sound is probably illegal everywhere and sonic booms are probably the worst thing that can happen to a normal neighborhood.
Ball bearing turbo instead of a fan?
Wow awesome! I was just thinking about this stuff today and there’s a video just uploaded yesterday all about it lol! What do you think about creating a ( i don’t know the exact terms) constricting nozzle that gets tighter like you see on some jest?
That’s the plan for the next version, I’m going to try and create more compression and fix an appropriate nozzle for the exhaust
instead of buying that cement maybe just use sodium silicate to bind and build up layers over the carbon fiber
I’ve never thought of doing this, I may try that next time. I mainly used the mortar because it was cheap and easily available.
@@JRYBuilds so is sodium silicate as concrete sealer, or you can make with sodium hydroxide (drain cleaner) and silica gel (crystal cat litter). ive always wondered how it would work with carbon fiber, you should do it.
Can you not create a smaller ram jet, So ypu end up with a sort of turbo jet set up, the ram jet is say 50mm reducing to 40mm to increase pressure. Yet still allowing faster moving air to bypass the ramjet also helping cool the outside. Hope that makes sence does in my head haha
That’s kind of what I’m trying to do, the problem is increasing mass flow rate which is a big factor in producing thrust
Amazing content i wish i found your channel sooner (ps. Sorry for my english it is not my native language
Someday there will be a job waiting for you at JPL. Don't stop making content or doing experiments, this is your resume.
Have you done any reading on oblique wave detonation engines?
Ramjet, one of the things I wanted to do at some point. I don’t remember but doesn’t a scramjet work at low speeds? (It is meant for even higher speeds)
The flame looked decently stable without the spike while it was inside the housing, spinning in a small vortex (this could be a bad think, idk), but I think a increase would help at the combustion point like you said.
I really like where you are going with this and hope to see more!
A ramjet combusts at subsonic speeds and a scramjet combusts at supersonic speeds, ram jets are used at subsonic speeds but are extremely inefficient below Mach 1
The flame might stable but it's a fancy blowtorch and not an engine. It's impossible to create significant thrust if the incoming air is subsonic. You need at least > Mach 1, better 2, ideally 3.
I wouldn’t call this a ram jet, but its still cool!
I actually agree, it technically isn’t a ramjet but it is more than just an afterburner. It just has a few similarities to a ramjet and for the sake of UA-cam it’s easier to call it a ramjet.
@@JRYBuilds i think it would be a hybrid jet engine. TechIncregients did a video about them awhile ago.
Maybe next time enclose the carbon fiber parts to prevent any stray frays you know
Just a idea for next time but dude I love you
Use a compressor?
What is your thrust increase ?
Far from an expert but isn't the spike supposed to be placed in the opposite direction for it to be working as a ram jet?
yes, I have seen some designs do what I did though and wanted to see what differences they would make. On a traditional ramjet there is no compressor so they use an aerospike for the compression stage.
@@JRYBuilds Okay, yeah that seems intersesting. Just started working on designing a simple jet engine myself but still working on the compressor design so I'm not close to working on the nozzle or combustor yet.
sir, have you thought of using a glow plug instead of sparkplug for ignition?
The air moving inside the chamber would cool the glow plug down too much for it to ignite the fuel.
Use turbo and fast rc Motor
133 subs for all this? i cant believe it, all my friends are knowing about u in the next 10 mins
How much thrust did it produce?
might I suggest you look up ejector ramjet? I think that this is what you are actually trying to make.
Never heard of it before, after reading up on it I’d say it’s very similar to what I’m trying to do.
Why don’t you make it out of cast metal it could provide a stronger base
I thought about doing that, but cast metal is too heavy for a setup like this. Aluminum would deform and steel is difficult to cast for an amateur setup
@@JRYBuilds maybe electro plate it with a more heat resistant material like hafnium carbide
why carbon fiber and not kevlar? cheers from Italy!
Kevlar has a very low melting point compared to carbon fiber which doesn’t have one at atmospheric pressure
@@JRYBuilds thank you!!!
I will definitely try to make this some day. Any tips?
Do your research and be very careful because you are working with highly flammable compressed fuel
what kind of a fuel injector did u use?
Pressurized butane is fed into a brass tube and out .75mm holes which are wrapped in a circle
You should just have these parts machined..
Scramjet no moving parts right.
how can i called scram jet if that have an fan
It's ramjet first
Second scarm jet or ramjet they use turbojet or Turbofan engine first then trun on ramjet and scarmjet engine after subsonic speed
Buy a used turbo.
this is not ramjet its afterburner edf
That is true, it’s more of a concept and not very practical but has taught me a lot about flow design. That was the main purpose of these “engines”
Ramjet ? Lol gtfo
It just a cigar lighter
What's the software after 7:05? I'm assuming it's some sort of CAD?
Fusion 360
Really fascinating. Can't stop thinking about it. May I have your email?