The reason the inside looks asymmetrical is because the rod is 12 inches long and I did not have a drill that could drill a hole in one pass all the way through, so the hole was drilled from each end hoping to meet in the middle. And well, the holes did not exactly meet up.
yes you are basically right. i ignited it by using steel wool and a car battery. you will not get any real thrust from it because the decomposition is too slow. It is really a device to demonstrate the principle of a hybrid motor.
Im very interested in a small scale version of this. So basically, you just have a rod of acrylic with a core drilled down it. Then you push O2 through it and ignite the acrylic? I can imagine this on a very small scale using a chemical oxygen generator
yes. substitute the gasous O2 with Liquid O2 or liquid nitros and the rod would burn in about a second and probably explode...which you could not watch safely. doing it this way allows a person to watch how it could work with a liquid oxidizer
could you make this on large scale, with a huge acrylic tube, and would that give thrust? I mean, maybe you could use the gasous 02 here with the larger contact surface, with the right nozzle there should be no explosion danger. certainly, the gasses can escape into the tube easily
The reason the background went black was because the camera I was using was trying to adjust for the change in brightness caused by the brightness of the motor firing. it got so bright that the CCD chip started to become staturated and caused the white vertical lines in the image. I am not an expert in ccd cameras and others might beter be able to explain the response. I hope that helps. This test firing was also near the end of the day, so the ammount of background light was diminishing.
Gr8 vid! Do you have any idea of the potential specific impulse for Acrylic and NOX or GOX? Is it a high power fuel & is it worth working with for flight? I can get the liquid resins and would like to experiment with it unless its a waste of time. Its convenient handling properties are attractive to me.
I do not have the details of the specific impulse for acrylic and NOX or GOX, but I do know it is out on the internet somewhere. You can get liquid resins from companies like Happco and cast your own, but motor uses a solid rod of acrylic which was drilled out to create the port.
Drilling might be easier then casting your own. Arylic is used in HPR hybrid motors, but you need to use liquid O2 or NOX and have a thrust chamber that CAN HANDLE THE PRESSURES GENERATED. this kind of motor is only a low pressure demonstrator.
I saw one motor that uses PVC pipe for the fuel (inside a metal motor casing).
On the GO2... you might want to add a flow meter in addition to pressure gauge. You can get them for MIG & TIG welding from places like Harbor Freight & Northern Tool (online) for reasonable price.
I'm planning to eventually build something for a bicycle (leaning towards valveless pulsejets)
good ideas about the flow meter, i am working on a beter system with some features that will make it more fun to run. I would like to build a PVC hybrid motor testbed also.
You can heat water under pressure (a few hundred °F). Once the water enters the nozzle it is superheated liquid and instantly vaporises to steam. You don't need a compressor to get the pressure either (heating the water develops the pressure).
It's actually a lot like a Liquid CO2 rocket but cheaper (and hotter, unfortunately).
i have not looked at steam rockets, generating the steam and its hazards i think are greater then the firey hibrid. I have thought about compressed gas, it would make an interesting demo and a way of lookng at different nozzle designs
The thrust has not been measured directly yet, I have the before and after mass of the rod, as well as the average GOX pressure supporting combustion. I will have to do some calculations to see what I can get out of those numbers. The trust was not a great amount however. The next generation demonstrator will be able to measure thrust, and have a more effiecent nozzle.
The fuel is acrylic and the oxidizer is gasous oxygen. We used a 12 volt car battery to spark a tuft of fine steel wool to create the initial source of combustion then added the O2
I have an oxy-acetylene troch, so I can get O2 gas easier than LO2. But was wondering about the sacrifice in density, and the added volume/size of the tank (for use on small vehicles)
I am using gaseous O2 fo this demo motor. I would not use liquid O2 because the density is so great, that I would not want to be close to this motor when it ignited. This motor is only good for showing the dynamics of the combustion process going on inside the fuel chamber.
does anyone know how to use H2 and O2 build a rocket?
saaaaaaaaaaaaas1 1 year ago
"STAND BY!"
Random laughing.
Everyone was rushing the rocket before we made sure it was safe. (I was there, and it was very neat to watch.)
majorkev 1 year ago
@deaftodd Lol i hope your trollin, if not you really are an ignorant idiot. lol
tekhed580 1 year ago
@deaftodd wow
miniatureme95 1 year ago
The reason the inside looks asymmetrical is because the rod is 12 inches long and I did not have a drill that could drill a hole in one pass all the way through, so the hole was drilled from each end hoping to meet in the middle. And well, the holes did not exactly meet up.
robertgissing 1 year ago 2
@robertgissing Crickey, with that sort of drilling misalignment how can you be a machining company!?
sadisticmisanthrope 8 months ago
Why does the fuel grain look asymmetrical? o.0
Because it's just or a test demo or because there is some science for this? =S
listerineman 1 year ago
wyglada slabo, ale ma zajebisty ciag ;]
MrM4rek 1 year ago
@MrM4rek um, what??
MrMitchprewett 5 months ago
Wow super cool demo!!! Love it!!
Longway2fall 2 years ago
looks like a short lasting light bulb
dominic600 2 years ago
it is really bright when you see it outside, and it is really loud too. thanks for the comment
robertgissing 2 years ago
That motor looks like it needs more oxygen because you are only getting limiter flow. If the motor was at full power the flame would be blue.
alejandroengineer 2 years ago
Comment removed
alejandroengineer 2 years ago
yes you are basically right. i ignited it by using steel wool and a car battery. you will not get any real thrust from it because the decomposition is too slow. It is really a device to demonstrate the principle of a hybrid motor.
robertgissing 3 years ago
Im very interested in a small scale version of this. So basically, you just have a rod of acrylic with a core drilled down it. Then you push O2 through it and ignite the acrylic? I can imagine this on a very small scale using a chemical oxygen generator
derjew 3 years ago
good luck getting off the ground!
Atevra 2 years ago
Is it able to power, well.. something, if so: what?
Adirondac0 3 years ago
the thrust is minuscule and is really about presenting the principle. How often do you get to watch a combustion of an article from the inside out.
robertgissing 3 years ago
Oke, but is this concept applied in rocket science?
Adirondac0 3 years ago
yes. substitute the gasous O2 with Liquid O2 or liquid nitros and the rod would burn in about a second and probably explode...which you could not watch safely. doing it this way allows a person to watch how it could work with a liquid oxidizer
robertgissing 3 years ago 2
could you make this on large scale, with a huge acrylic tube, and would that give thrust? I mean, maybe you could use the gasous 02 here with the larger contact surface, with the right nozzle there should be no explosion danger. certainly, the gasses can escape into the tube easily
Adirondac0 3 years ago
This comment has received too many negative votes show
y did every thing go black is it fake???
benedyktmatraszek 4 years ago
The reason the background went black was because the camera I was using was trying to adjust for the change in brightness caused by the brightness of the motor firing. it got so bright that the CCD chip started to become staturated and caused the white vertical lines in the image. I am not an expert in ccd cameras and others might beter be able to explain the response. I hope that helps. This test firing was also near the end of the day, so the ammount of background light was diminishing.
robertgissing 4 years ago
WoahhH! Did you see the EMP that thing was giving off?
metguru 4 years ago
i don't think it is EMP, but the CCD in the camera bleeding over into each other because it is so bright.
robertgissing 4 years ago
nice emp.
jake497 4 years ago
ZOMG that EMP was massiv!
(Morons)
r0ck3tsm0k3 3 years ago
Gr8 vid! Do you have any idea of the potential specific impulse for Acrylic and NOX or GOX? Is it a high power fuel & is it worth working with for flight? I can get the liquid resins and would like to experiment with it unless its a waste of time. Its convenient handling properties are attractive to me.
rnsaza 4 years ago
I do not have the details of the specific impulse for acrylic and NOX or GOX, but I do know it is out on the internet somewhere. You can get liquid resins from companies like Happco and cast your own, but motor uses a solid rod of acrylic which was drilled out to create the port.
robertgissing 4 years ago
Drilling might be easier then casting your own. Arylic is used in HPR hybrid motors, but you need to use liquid O2 or NOX and have a thrust chamber that CAN HANDLE THE PRESSURES GENERATED. this kind of motor is only a low pressure demonstrator.
robertgissing 4 years ago
cool, thanx
rnsaza 4 years ago
I saw one motor that uses PVC pipe for the fuel (inside a metal motor casing).
On the GO2... you might want to add a flow meter in addition to pressure gauge. You can get them for MIG & TIG welding from places like Harbor Freight & Northern Tool (online) for reasonable price.
I'm planning to eventually build something for a bicycle (leaning towards valveless pulsejets)
KanzlerM 4 years ago
good ideas about the flow meter, i am working on a beter system with some features that will make it more fun to run. I would like to build a PVC hybrid motor testbed also.
robertgissing 4 years ago
Man, I wish I had more time for fun stuff.
After we go through the sailboat racing phase we might start doing this stuff (My kids are approaching a good age for rocket science).
I do plan to build the Elektra I $10 valveless pulsejet to give them a taste of it since I'll be welding EMT anyway for another project soon.
KanzlerM 4 years ago
Have you looked at steam rockets?
You can heat water under pressure (a few hundred °F). Once the water enters the nozzle it is superheated liquid and instantly vaporises to steam. You don't need a compressor to get the pressure either (heating the water develops the pressure).
It's actually a lot like a Liquid CO2 rocket but cheaper (and hotter, unfortunately).
KanzlerM 4 years ago
i have not looked at steam rockets, generating the steam and its hazards i think are greater then the firey hibrid. I have thought about compressed gas, it would make an interesting demo and a way of lookng at different nozzle designs
robertgissing 4 years ago
the exhaust doesnt look like really high velocity, what thrust are you getting from that? Or has it not been measured yet?
Still, nice work
DynamiteDanmah 4 years ago
The thrust has not been measured directly yet, I have the before and after mass of the rod, as well as the average GOX pressure supporting combustion. I will have to do some calculations to see what I can get out of those numbers. The trust was not a great amount however. The next generation demonstrator will be able to measure thrust, and have a more effiecent nozzle.
robertgissing 4 years ago
the transparent part is made of...?
lincoherent 5 years ago
The transparent part is made from optical grade acrylic and is the fuel being burned. In this way, the combustion process can be viewed easily.
robertgissing 5 years ago
The fuel is acrylic and the oxidizer is gasous oxygen. We used a 12 volt car battery to spark a tuft of fine steel wool to create the initial source of combustion then added the O2
robertgissing 5 years ago
I was wondering about using gaseous O2.
I have an oxy-acetylene troch, so I can get O2 gas easier than LO2. But was wondering about the sacrifice in density, and the added volume/size of the tank (for use on small vehicles)
KanzlerM 4 years ago
I am using gaseous O2 fo this demo motor. I would not use liquid O2 because the density is so great, that I would not want to be close to this motor when it ignited. This motor is only good for showing the dynamics of the combustion process going on inside the fuel chamber.
robertgissing 4 years ago
powered by wat?
rapidrory 5 years ago