Liquid rockets

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Will I will put that bet again it's an IDEA my plans are terrible I came up with all of this today and that's my idea if I give you guys all my plans once I read all the books I need reading one now I will get my rocket in the air I don't care if it blows upon lift off or in the air success only comes with failure and just so all you guys know my uncle works with rockets and send s them to space he also works with the chemicals that run the engine so aksrockets your on

So you're uncle helps. He can't design it and build it. That has to be you. He can just supply the materials.
Where does your uncle work?

Alex
 
Just so u know I might not do it it's a idea I might not even make it probably use my other rockets for the fair I was just thinking and u guys are no hope
 
Will I will put that bet again it's an IDEA my plans are terrible I came up with all of this today and that's my idea if I give you guys all my plans once I read all the books I need reading one now I will get my rocket in the air I don't care if it blows upon lift off or in the air success only comes with failure and just so all you guys know my uncle works with rockets and send s them to space he also works with the chemicals that run the engine so aksrockets your on

Cruzre I allready said that in here
 
Hmmm, trying to decide if this is a troll, a kid, or the classic "make two accounts and have them compete", notice that both "high powered" and "Witch Doctor" have the same join date?

2576136-obvious_troll_wedding.jpg
 
Kid, If you completely scratch build a liquid powered rocket with the plans you laid out and it reaches, say... 2500 feet (I was going to say space but that seems like its's a little to hard). I will give you every single rocket related item I own (worth about $1000) provided you have pictures and videos of the flight.
How's that sounding... :wink:

Deadline: Let's say a year.

Alex

If you say that, he might try it and put people (possibly himself) in grave danger.
 
Here I think I could get help but just an idea has made me think of not doing it all I wanted was advice with some facts not opinion
 
Wouldnt the government get involved ??
FBI CIA wondering why the hell would you build a liquid fueled rocket ?
 
If you say that, he might try it and put people (possibly himself) in grave danger.

Exactly I have an idea I am not for competition and no I would never hurt anyone I can barely kill a spider without regretting it
 
Wouldnt the government get involved ??
FBI CIA wondering why the hell would you build a liquid fueled rocket ?

well one reason I want to is that I think nasa rockets burning liquid Is cooler then solid fuel second it would be awsome if. Built one from scratch third it is a challenge most people won't take on
 
My advice, and the collective advice of, I believe, quite a lot of people on the forum is: slow down! Liquid engines are one of the most complex, dangerous, and fragile pieces of engineering known to man. Solid rocket motors are great, they work well, are reliable, and best of all, robust, plus there is still plenty of experimentation to be done with them. There are tons of threads and advice on this forum. Register with NAR or Tripoli, participate in their junior programs if you are young enough, if you are older, tell us the state, not city, not zip code, the state or country you live in and there are tons of people who can recommend a good club or field to go to. Everyone here is more than willing to help, just don't ignore their advice.

If you are dead set on developing liquid engines and want to make your wallet cry, go join Armadillo Aerospace and the good (slightly burned) folks out at Friends of Amateur Rocketry. Most of them do this stuff for a living, and they have the experience and results to prove it. And Remember...

bush.jpg
 
Uhm what kind of chemicals? Not sure how old you are so I won't blatantly point it out but please work on your grammar.

I am not checking my mistakes I am just thinking what pops in my head the chemicals I am not sure i think it was a new fuel for cars
 
If you want facts, here is the deal:

Basically, you are expecting that boiling liquid nitrogen by putting it next to water is going to provide enough pressure and mass flow to lift a rocket.

It's not going to work.

The power output of the motor can be at the most the rate of heat going into liquid nitrogen, which won't be terribly fast. When you put liquid nitrogen in contact with anything warm, it bubbles violently enough that it insulates itself, reducing the heat transfer and thus the rate of boiling.
On the other side of this pipe, the water will freeze immediately. Instantaneously. This will form a big insulating layer preventing heat transfer, and thus power output.
 
My advice, and the collective advice of, I believe, quite a lot of people on the forum is: slow down! Liquid engines are one of the most complex, dangerous, and fragile pieces of engineering known to man. Solid rocket motors are great, they work well, are reliable, and best of all, robust, plus there is still plenty of experimentation to be done with them. There are tons of threads and advice on this forum. Register with NAR or Tripoli, participate in their junior programs if you are young enough, if you are older, tell us the state, not city, not zip code, the state or country you live in and there are tons of people who can recommend a good club or field to go to. Everyone here is more than willing to help, just don't ignore their advice.

If you are dead set on developing liquid engines and want to make your wallet cry, go join Armadillo Aerospace and the good (slightly burned) folks out at Friends of Amateur Rocketry. Most of them do this stuff for a living, and they have the experience and results to prove it. And Remember...

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thank you I am not dead set on doing this I now the dangers with the wallet cry part it won't be anything special mybe a hybrid engine not the moon like 100 ft
 
Wouldnt that cost thousands dollars ? the fuel tanks and just the build in general
 
If you want facts, here is the deal:

Basically, you are expecting that boiling liquid nitrogen by putting it next to water is going to provide enough pressure and mass flow to lift a rocket.

It's not going to work.

The power output of the motor can be at the most the rate of heat going into liquid nitrogen, which won't be terribly fast. When you put liquid nitrogen in contact with anything warm, it bubbles violently enough that it insulates itself, reducing the heat transfer and thus the rate of boiling.
On the other side of this pipe, the water will freeze immediately. Instantaneously. This will form a big insulating layer preventing heat transfer, and thus power output.

Now see that's some info I can work with and with heat I think that I will not burn it by use newtons law for every reaction thier is a opposite but equal reaction
 
If you say that, he might try it and put people (possibly himself) in grave danger.

Oh. True. Guess I shouldn't be encouraging that kind of behavior.
DONT DO IT!
Here I think I could get help but just an idea has made me think of not doing it all I wanted was advice with some facts not opinion
Well, if you would have read the forum rules, you would have understood that we can't talk about how to make motors on here.
My advice:Start smart. Go to your local hobby shop and buy a model rocket kit and a few engines. That might seem a little underwhelming compared to your plans right now, but it's a heck of a lot safer and less stressful. You can progress upward from that.
I'll be serious for a second: Liquid engines are insanely complex. Definitely not something you would do for a science fair project. It usually takes a team of a adults years to successfully complete one. I can promise you they have access to more stuff then your uncle does. Even if you do have a design that would work it would take THOUSANDS of dollars for it to become a reality.

Alex
 
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Wouldnt that cost thousands dollars ? the fuel tanks and just the build in general

I don't think so if I get a a tiny tube that actully Carrys liquid nitrogen like the container they ship it in I could put hat in the rocket it would just need to be small
 
Mmmm...once sentence answers. Anyway, hybrids are fine, just expensive, very, very expensive if you have to buy the Ground Support Equipment. Solid motors are cheap and easy for a reason, they are made from a thick liquid that you can pour and then hardens, making motor production (relatively) easy. There are a lot of great, inexpensive kits out there, Loc Precision, Wildman, Rocketry Warehouse, much bigger and better (only in my opinion, I know) than Estes. You can still source and buy hybrid engines from RATTworks and Contrail, they will sell you a great, reliable, and CERTIFIED system.

Also, if this is a troll than I am responding too him, I apologize in advance mods.
 
Seriously take Witch Doctors (uh-hum clears throat) advice and start a thread asking for good ideas for a science fair project. HINT: liquid motors is not one of them.

...Maybe build different estes kits and see how fin shape effects performance or something safer like that. And please make sure you have adult supervision when doing so.
 
Oh. True. Guess I shouldn't be encouraging that kind of behavior.
DONT DO IT!

Well, if you would have read the forum rules, you would have understood that we can't talk about how to make motors on here.
My advice:Start smart. Go to your local hobby shop and buy a model rocket kit and a few engines. That might seem a little underwhelming compared to your plans right now, but it's a heck of a lot safer and less stressful. You can progress upward from that.
I'll be serious for a second: Liquid engines are insanely complex. Definitely not something you would do for a science fair project. It usually takes a team of a adults years to successfully complete one. And I can promise you they have access to more stuff then your uncle does. Even if you do have a design that would work it would take THOUSANDS of dollars for it to become a reality.

Alex


Ok I have allready built and launched about 30 rockets all solid not asking how to make engines just the properties of nitrogen and all the math and resources how to accomplish it and if it turns to complicate I will abandon it
 
Basically, the hotter and faster moving the exhaust the better the propellant. Heating liquid nitrogen up to the temperature of hot water won't make it a good propellant.
 
Ok then I guess I will do my back up using my b4s and c11 looking for different altitudes for my science fair idea is thier any other protects I could do.
 
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