Sciencemadness Discussion Board - Solid state rocket propellant

Solid state rocket propellant

Science is my middle name - 22-3-2016 at 09:15

I would like to build a test rocket to take a picture/video of the curvature of the earth, currently my plan is to build a three stage rocket were the first stage is composed of 3 solid propellant boosters to send the rocket 1/3 of the way up. The second stage will be a LOX and LH2 liquid fueled rocket engine to get it almost 2/3 of the way up with the third stage simply separating from the second stage and allowing enough time to deploy a parachute and delicate equipment such as a thermometer and visual streaming feed to save the video if the parachute fails. Does anyone have ideas for a strong enough propellant for the first stage? Ammonium perchlorate and aluminum powder + binder?

Aurium - 22-3-2016 at 09:55

Consider a high altitude balloon. Not as cool but much more feasible for amateur.

hissingnoise - 22-3-2016 at 10:57

Or a camera with wide-angle lens on a pole?

Science is my middle name - 22-3-2016 at 11:11

I really don't think a wide angle lens on a pole will work. I have already built the second stage of the rocket and I'm not going to disassemble it.
Does anyone have ideas for the fuel for stage 1.

Sciencemasta - 22-3-2016 at 11:44

I think you should use a hot air balloon because it will be simple to get /make

hissingnoise - 22-3-2016 at 12:01

Quote:

I really don't think a wide angle lens on a pole will work.

Sorry Sn, I can resist anything but the slightest temptation to take the piss . . .

Welcome to scimad!

Science is my middle name - 22-3-2016 at 12:22

Does anyone have any ideas for a solid state rocket propellant.
What about
16% Aluminum powder
69.6% Ammonium perchlorate
0.4% Iron (III) Oxide
12.4% PBAN binder
1.6% Epoxy curing agent
Would this work?

Aurium - 22-3-2016 at 12:23

luna-park-slingshot-e1439518666669.jpg - 33kB

Or build a giant slingshot and fling a camera ball into the blue.

But wait you already have the LOX/LH2 stage built?? Now that's something it'd like to see.

Science is my middle name - 22-3-2016 at 12:24

I don't have a camera yet
It should be here in about a week

Herr Haber - 22-3-2016 at 12:59

Your idea is correct.
Now, I'm pretty sure that people who might be able to help you would do so more willingly if you demonstrated something that would make them take you seriously.
Any previous achievements perhaps?

Because saying you already have a liquid oxygen and hydrogen second stage is no small feat. You must have some data to share I hope? Burn time, thrust, projected weight of the whole rocket and it's different stages, etc
.
There are some "rocket scientists" (not me) around here who might help you a long way if you show you are serious and already have some "know how".

Science is my middle name - 22-3-2016 at 13:32

I get what your saying but really this is my first major thing. My friends were starting this and they asked me if I had any ideas so I decided to help them. They work mostly with mechanical and electrical things while I am the chemist of the group. Currently I'm at school and the half built rocket is at there house.

Science is my middle name - 22-3-2016 at 13:53

One of my friends sent me an extremely rough sketch he quickly doodled out. We are all in school right now though.

Aurium - 22-3-2016 at 14:22

Go for it! I'm sure you'll learn something along the way.

hyfalcon - 22-3-2016 at 15:03

Don't know where you plan to launch this thing at, but something that weighs more than a ton has some liability attached to it IF it gets off the ground and IF it doesn't blow up on the launch pad it will have to come down somewhere. Have you thought of any of that? Landing zone?

PHILOU Zrealone - 22-3-2016 at 15:22

If your rocket goes on a strange unpredicted pathway or cato for a reason or another ... destroying personal/civilian/natural structure ... scaring, injuring or killing people...you might be in serious troubles...

It could also be considered a treat of terrorism or nuclear missile and be destroyed by military forces...without flying rights...maybe crossing civilian aerial transport...

So such big rockets are a lot of troubles...good luck!

Science is my middle name - 22-3-2016 at 15:57

My friends are taking care of that. We are going to get a permit from the FAA and get it all the way down to the mohaji desert in Southern California where there are several amateur rocketry groups. The main thing is getting the permit though.

Oscilllator - 23-3-2016 at 03:10

Quote: Originally posted by Science is my middle name

My friends are taking care of that. We are going to get a permit from the FAA and get it all the way down to the mohaji desert in Southern California where there are several amateur rocketry groups. The main thing is getting the permit though.

I really think you should build a few small rockets before you go for a 3-stage one. Have you tried building some small sugar rockets to start with? They can be great fun and teach the basics of rocket building.

j_sum1 - 23-3-2016 at 03:33

With that in mind, I recommend yt channel "The king of random". He has a nice series on rockets and some really good ideas.

NedsHead - 23-3-2016 at 04:35

Sugar rockets are great fun, I took a 1.5kg (no nozzle) KNSU rocket out into the desert a few weeks ago, I'll share the footage when I catch up with my friend who filmed it (soon I hope) I didn't spend much time making the motor cases but they turned out fine.

[Edited on 23-3-2016 by NedsHead]

Science is my middle name - 23-3-2016 at 07:10

I have built loads of small sugar rockets about 18" tall to 36" tall I have even tested KNO3 + another fuel to make new fuels and learn about the properties of certain fuels. Also I frequently watch grant thompsons king of random vids.

Microtek - 23-3-2016 at 07:20

Beside the risks and technical difficulties, have you thought about the expense? If you are in school, I'm guessing you don't have a large income, and a litteral ton of chemicals can be expensive (even if they are not particularly exotic).

Having said that, and assuming you are not simply trolling, go with a composite propellant similar to the ones used in other space programs. You'll want something that's tried and tested and you'll want to read huge amounts of technical litterature to establish exactly how to prepare and load the propellant grain. Knowing the chemical makeup of the propellant is just scraping the surface of what you need. If, say, your processing of the propellant before curing isn't good enough, you could easily end up with large bubbles in the grain which could lead to CATO.
There's also the questions of grain geometry, body- and nozzle materials (you need a protracted burn which is very demanding of the materials) and aerodynamics. You have a LOT of reading ahead of you.

Herr Haber - 23-3-2016 at 14:26

Quote: Originally posted by NedsHead

I'll share the footage when I catch up with my friend who filmed it (soon I hope) I didn't spend much time making the motor cases but they turned out fine.

[Edited on 23-3-2016 by NedsHead]

Yes, I'd like to see that !

NedsHead - 27-3-2016 at 22:33

"Core diameter? meh.. I'll just eyeball it" https://www.youtube.com/watch?v=jwvW-u9_igI

Oscilllator - 27-3-2016 at 22:42

Quote: Originally posted by NedsHead

"Core diameter? meh.. I'll just eyeball it" https://www.youtube.com/watch?v=jwvW-u9_igI

NedsHead I've had this exact same problem and I rather suspect it had less to do with core diameter and more to do with numerous cracks in the fuel, massively increasing the surface area. I suspect there is a very good reason why NASA uses pourable, rubberised propellant.
How did you drill your cores though? I have personally found that to be the limiting factor when it came to reasonably sized rockets. It's extremely difficult to drill a core after it has been packed, and equally difficult to get a good packing with a rod of the correct diameter sitting inside the rocket ready to be pulled out once it is packed.

NedsHead - 28-3-2016 at 00:19

you could be right about the cracks Oscilllator, I did the coring while the fuel was still hot and pliable just after pouring, I don't think the coring itself was the problem, most likely the hours of rough travel to the launch location that might have cracked the fuel.

I made a jig from scrap steel to do the core and it worked quite well, I clamped the coring rod in my lathe and turned it slowly while I fed the rocket in from the other end by hand and gave it an occasional spray of silicon.

[Edited on 28-3-2016 by NedsHead]

chemrox - 28-3-2016 at 01:14

powdered sulfur and aluminum mix in alcohol and cast with a wax star shaped insert to be melted out after the cast sets. Goes like hell!

Oscilllator - 28-3-2016 at 02:00

Wow Nedhead, that's a nice jig! I made one out of scrap wood, but I didn't have a lathe so I made it by bolting a drill onto the jig. It had the unfortunate disadvantage that I had to hold the rocket by hand though. The extra long drill bit I used also snapped in one of the rockets, as I could never find a good lubricant and so the propellant kind of set around the dill bit, holding it tightly. Next time I'll be sure to try silicon.

NedsHead - 28-3-2016 at 02:26

Thanks Oscillltor, a smooth coring tool used with silicon spray from the hardware store work well for me, I took the idea from this guy https://www.youtube.com/watch?v=hyPysthIRss

Canerican - 5-4-2016 at 18:00

I estimate that the process of designing and building the cryogenic turbopumps for your second stage would take 2 years and cost 20,000 dollars if you and your friends can get a deal at the local precision machining company. If you want to make them yourself I just saw a really nice Haas 4-axis CNC mill on ebay for only 90,000 dollars.

On a serious note I suggest you head over to Richard Nakka's experimental rocketry website at http://www.nakka-rocketry.net

[Edited on 6-4-2016 by Canerican]

NedsHead - 18-4-2016 at 05:54

I was back in the South Australian desert this weekend and took the opportunity to try out some more KNSU rockets, I'm still having some issues with core diameter and thrust but my rockets are slowly improving. https://www.youtube.com/watch?v=_MEW9tOEFc4

Aurium - 19-4-2016 at 09:02

On the subject of liquid fueled rockets, maybe one could find more feasible to build a hybrid motor.
Liquid, room temperature red HNO3 + an acrylic solid fuel.
This would also make pump design much simpler due to the no cryogenic liquids.
An electric powered gerotor stainless steel pump might be enough.
Keeping the nozzle cool would still be a nightmare though

XeonTheMGPony - 19-4-2016 at 09:20

Quote: Originally posted by Aurium

On the subject of liquid fueled rockets, maybe one could find more feasible to build a hybrid motor.
Liquid, room temperature red HNO3 + an acrylic solid fuel.
This would also make pump design much simpler due to the no cryogenic liquids.
An electric powered gerotor stainless steel pump might be enough.
Keeping the nozzle cool would still be a nightmare though

Actually you use the fuel to cool the nozzle at the same time super heating the fuel. I used this in my Alcohol rocket engines.

A CO2 cartridge pressurized the alcohol, and drove an O2 regulator to match the pressure to the alcohol feed pressure, then a needle valve assembly driven by servo to throttle the thrust.

Needle valves operated 1:1 and a secondary mix valve to control fuel to oxidizer ratio, they where operated via engine back pressure.

The engine burn time was sadly limited to using gas phase O2, But if one where so lucky to have LO2 sure a modified system would do well.

aga - 19-4-2016 at 09:58

Just had an idea and did not know where else to put it, so here it is :

deltaH had the idea of a factice (artificial rubber) rocket motor.

I was wondering ....

Activate some charcoal (ball mill it) and then boil in dilute (5%) HCl for about 20 mins to 'clean' it. Dry thoroughly in an oven. Cool.

Flood the fresh AC with pure oxygen for as long as you dare.

Rapidly mix with very cold vegetable oil (to trap the O₂ in the AC).

React with very cold S₂Cl₂ keeping the reaction mixture as cold as possible.

The result should be a solid rubbery lump of plenty of fuel and plenty of oxidisers.

Canerican - 19-4-2016 at 21:23

More energetic results could probably be obtained by soaking the charcoal in liquid oxygen instead of flooding with gaseous oxygen. Of course, that process would produce a very sensitive oxyliquit explosive.

LOX usually requires licenses to purchase. A quick search of the forums reveals that many members have instead purchased completely unregulated liquid nitrogen and condensed gaseous oxygen from various sources

Oscilllator - 20-4-2016 at 00:02

Quote: Originally posted by aga

Just had an idea and did not know where else to put it, so here it is :

deltaH had the idea of a factice (artificial rubber) rocket motor.

I was wondering ....

Activate some charcoal (ball mill it) and then boil in dilute (5%) HCl for about 20 mins to 'clean' it. Dry thoroughly in an oven. Cool.

Flood the fresh AC with pure oxygen for as long as you dare.

Rapidly mix with very cold vegetable oil (to trap the O₂ in the AC).

React with very cold S₂Cl₂ keeping the reaction mixture as cold as possible.

The result should be a solid rubbery lump of plenty of fuel and plenty of oxidisers.

Other than how this is an incredibly dangerous idea and should never every be done by a human, the problem with this method is that
1)The freezing point of S₂Cl₂is above the boiling point of oxygen, so it's guaranteed to freeze so it won't react with the vegetable oil
2) When the mixture warms up the oxygen will expand, breaking up the fuel mixture.

PHILOU Zrealone - 20-4-2016 at 04:32

Quote: Originally posted by aga

Assuming O2 to be a perfect gas, one mole or approx 32gr will take 22,41 Liters of volume at STP.
This means that 12gr (approx 1 mole) of your activated C would need to catch at least 22,41 L of gaseous O2 (or 32gr) to get to perfect OB
--> this would deliver 44 gr in fine or 44gr of CO2 after exploding.

This seems way too much (African idiom: Someone eating entire coconuts in one swallowing has full trust in its own anus

)
If it does, it would be hell an explosive and burning very hot.
But it doesn't because at best AC catch 1/3 of its weight of gasous compounds that display a strong affinity for it (gaseous hydrocarbons)...and O2 should be weakly adsorbed.

You also add the disulfide bridges and vegetable oil as external matrix what reduces the overal OB in very negative regios
--> Without external oxydizers, it won't work better than burning lamp oil or candle.

[Edited on 20-4-2016 by PHILOU Zrealone]

Chemist_Cup_Noodles - 26-4-2016 at 08:17

Quote: Originally posted by chemrox

powdered sulfur and aluminum mix in alcohol and cast with a wax star shaped insert to be melted out after the cast sets. Goes like hell!

This mixture rings a bell. Actually I believe it is quite similar to the "zincoshine" mixture that Homer Hickam Jr (of Rocket Boys/ October Sky) used. Except instead of aluminum powder, he used zinc powder which was likely far cheaper and more accessible. So really this mixture should be getting some more attention I'd say. It's easy to cast as it's a hybrid rocket fuel (so not totally solid, but oh well). Not too sure about it's specific impulse or energy density though.