Hi this is not a rocket project but a reactor motor project using rocket motors???

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RE:init 6
thanks for the tip on Newtons third formula

I will check them out next week


RE:SCE to AUX
generating heat for catalyst is a important question
First I need to find out what is the catalyst and how big it is and how much heat it needs

Assuming the heat can be supplied with vituly short circuiting the catalyst across a nicad battery a 70 gram 2400 cell will deliver ~100 amps for some 30 seconds before its runs out of power so 1volt *100amps makes 100watts of heat
more heat regured would mean bigger battery or less heat smaller battery

preferably the solution would be mayby simple lighter procces like a cigerrate lighter with gas that turns on a few seconds ahead of the use to pre heat the catalyst and then as the process is I think heat generating(exothermic ) that will supply the heat for the 3 second to 5 second run hopefully done in away not to ignite the gasses as flame for primitive early versions could add to much complexity

This type of motor proposed can be very seriously heavy compared to rocketry as the weight of the motor is lifted with large wings and thrust ratios are guite low 4kg on AUW take off to fly craft of ~1.2KGs ratio ~3.5:1 which for rocketry is exremly low so it realy reactor stuff

The simplest easiest solution the use of 80% H2O2 isnt possible due to the eneormous seriously enormous problems and costs to get it so its think up something else and N2O nitrous oxide is looking good f the catalyst isnt to expensive and heavy and dosnt need too much starting heat
cant find much info on the net

Again the point of this thread is not to prove what I know and dont know about rocketry as I am not out to make a rocketry project but a low power reactor motor derived from mixxing model RC plane material which I know and elements of rocketry which I can get know if as i conduct trials and experments

First preferences would be buy from off the shelf if it existed at reasonable prices

no sign of that
modify kits but thats not looking to hot an idea so far

Make from plans but the nearest contender solaire gasoline rockket uses the hydrogen peroxide H2O2 so that banjaxed that idea

next idea research any thing similar at all and try to make it or design it and then mayby get say my friends in eastern europe with acces to lathes and things to rattle up a proto type

When the craft is in the air and it lights up and if it goes bang well it will be a serous distance from me falling down onto nowhere ville farming land in stickville

The stactic tests will be done in suitable bunkers to keep noise down to neighbours and 4KG reactor motors cant blow a house to bits not even a brick wall down so the risks are low

N2O2 isnt a realy super dangerous gas if used correctly so I fail to see where I hurt myself seeing as I regularly use 6KG pulse jets and propellers making
10 bhp plus on models which when they shed a prop can be fun to be near

I regret that not being rich and not doing cheque book modeling I tend to try to get the maxxuim power per $$$ I can get

The reason I keep asking what happenes if you mix KNO3 with for example fuels is nobody from any rocketry forums or chemistry forums I pose this question to has any idea
Lots and lots of theories but no imperical facts
and I am not keen to go to a lot of time and trobble to source this stuff and make this mix if all it makes is a shock sensitive fuel which is then absolutly useless to me and cost me money and time
however if the awnswer does not eventualy arrive I will be forced to to conduct limited experments



JATO
 
Seems Slope soaring racers are doing over 300mph without rocket engines.

https://www.sloperacing.com/results/ds-speeds.htm

I saw a post saying a pilot in Nor-Cal get 308mph yesterday. Since slope racers can do 308 then some dual stage electric is out their that can do some really push the limit speed.

I would bet searching for that will be cheaper then any liquid motor will ever be after 10 grand's worth of testing. Based on the required weight alone. Liquid motors for rockets are heavy.

Nitrous motors have a large mass fraction.
 
Lol, not much. JATO, these things may seem impressive at first, but they barely produce much thrust. If you look closely, the so called 'jet engine' isn't even secured to the table in any way and it didn't budge once during the firings.

This is part of an email from the maker of that video:
This gives no thrust whatsoever and it is a nightmare to get started, but it is a nice demonstration of the principle.
 
You could build a ramjet from 26ga stainless steel with an entrance area of about 8 inches. Without ignition system, fuel, fuel pump it would weigh ~2.5lbs and at 250mph would produce about 4.5lbs of net thrust thrust(not including weight of fuel, pump, fuel tubing, ignition system, etc). With a ramjet the faster you go, more thrust is produced so that same ramjet would produce ~10lbs of net thrust (same restrictions as before) at about 350mph. As an added benefit, you could fuel it with kerosene or isopropyl(IPA) or even propane.

Realistically, your best low cost solution would be to use solid rocket motors. The per-flight cost is higher but the initial motor investment and R&D investment (both in money and in time) would be much lower. The weight of a solid rocket motor is going to be MUCH lower than any other solution as well. You're not going to find an easier solution than a solid rocket motor.

-Aaron
 
Re:heada

ram jet isnt the plan its too similar to pulse jet too big for too little thrust

The solid fuel version with twenty second burn looks to be similar weights to liquid fuel versions

In the three second single burst its light eneogh but then landing after every three seconds burn is a drag

I havent established Liquid fuel versions are so impossible in the low powers and low compression I probably need

I figure there exists possibilties not tried out like pre oxegenating the fuel to reduce the needs for so much oxegen as they havent tried out all the posibilties in fuel mixxes as the requrements to do rockets to carry people to space limited the fuels possiblties

i saw it is possible to use N2O and dissolve it into liquid methane but no mention if it became shock sensitive

realy i cant figurre the rocket guys at all it seems they dont dont know the half the fuels out there once it isnt LOX and liquid hydrogen or similar simplistic fuels

until i have established that dissolving oxadent into fuels wont work there is lots of work to be done

Lucky i have the advantage that i start with a blank sheet and can inquire into every type of fuel possible until i find the best one

if i find a fuel that is mostly oxegenated with its fuel component then it would be similar to a mono prop inject and get power

it might not work so well at very high compression ratios but might work at lowwer compression ratios wher speeds sub sonic would work for my project


RE:ghost
I expect a thin tin motor not to have high compression and therfore low thrust or even no thrust

its the interesting possibilty to start with the more easy solution and gradualy beef it up and gradualy increase fuel rates and compression rates to incremently find suffient power

RE:Art Upton

Oh yeah these guys get 30mph plus
but first you need a montian and then 30mph plus winds

no wind no speed no mountian no speed

rocket reactor will hopefully work every place

keep you guys posted

JATO
 
I'll try to go over this in some detail:

Re:heada

ram jet isnt the plan its too similar to pulse jet too big for too little thrust

The solid fuel version with twenty second burn looks to be similar weights to liquid fuel versions

Where are you getting your weight estimates for the liquid fuel motors? Many people are telling you that for what you want, solids are the most practical, cheapest, and lightest and yet you persist in your insistence on liquid fuel.

Honestly, I would be stunned if anything homemade could achieve a specific impulse greater than 200 seconds or so in a liquid fuel rocket. This is about what current commercial solid motors are at as well (depending on the specific motor), so there is no efficiency advantage to the liquid fueled design by amount of fuel. Because of this, it all comes down to mass fraction. A liquid fuel design requires at minimum a set of pressurized tanks, piping, injectors, a combustion chamber (which needs to be tremendously heat resistant) and a nozzle (same qualification as the combustion chamber). A solid motor needs a thin walled aluminum case and a nozzle. Since it is designed to be fired once, the nozzle needs far less heat resistance than the liquid fuel equivalent, and also can be ablative to dissipate heat. Between these two designs, the solid fueled one will almost assuredly have a better mass fraction, resulting in a lighter weight for the same performance.

In the three second single burst its light eneogh but then landing after every three seconds burn is a drag
The simplest and easiest solution to this desire is simply to use multiple solid fuel motors on separate ignition circuits. This is simple, elegant, and completely eliminates the need for a restartable liquid fuel motor - a significant engineering challenge that would cost quite a bit in resources, time, and probably failed prototypes.

I havent established Liquid fuel versions are so impossible in the low powers and low compression I probably need
The lower pressure you run, the lower the efficiency, and it does not eliminate the problems with heat. Also, the lower the efficiency, the heavier the load of fuel required for a given task, resulting in solids gaining an even larger advantage in weight.

I figure there exists possibilties not tried out like pre oxegenating the fuel to reduce the needs for so much oxegen as they havent tried out all the posibilties in fuel mixxes as the requrements to do rockets to carry people to space limited the fuels possiblties
Pre-oxygenating the fuel? That means one of two things - either the fuel in the tank will burn with its oxygen, resulting in a rather spectacular disassembly on ignition, or it would have to be stable enough to require a catalyst, resulting in other problems with designing the proper catalyst beds.

i saw it is possible to use N2O and dissolve it into liquid methane but no mention if it became shock sensitive
There is always the problem that if it is pre-oxygenated at all, if any of it lights, it burns far faster and more violently than fuel alone, making it far more dangerous. There is a VERY good reason why in basically all liquid fuel rockets, the fuel and oxidizer are kept completely separate until the combustion chamber, with the exception of some of the catalyzed monopropellants.

realy i cant figurre the rocket guys at all it seems they dont dont know the half the fuels out there once it isnt LOX and liquid hydrogen or similar simplistic fuels
Actually, it is you who doesn't understand much about rocketry, and in your stubborn insistence on claiming additional knowledge, you are likely to end up spending more money for a worse result than if you just took our advice in the first place. Also, I don't know why you call lox and LH2 simplistic - they are among the more difficult fuels to work with for amateurs - they are used because of their tremendous power and efficiency per weight of fuel - resulting in specific impulses in the 400+ second range (compared with 150-250 for most amateur motors).

until i have established that dissolving oxadent into fuels wont work there is lots of work to be done
As stated before, you really do not want to be dissolving the oxidizer into the fuels - that is a recipe for disaster.

Lucky i have the advantage that i start with a blank sheet and can inquire into every type of fuel possible until i find the best one
Unluckily, you start with both a blank sheet and insistence that you are more knowledgeable than people who have studied rocketry for years, including several professionals in the aerospace industry. Not to be rude, but perhaps you should start taking the advice of those who have looked into many propulsive methods, and understand the complexities, advantages, and disadvantages involved in various types of propulsion.

if i find a fuel that is mostly oxegenated with its fuel component then it would be similar to a mono prop inject and get power
If it is preoxygenated and volatile enough to be used as an uncatalyzed monopropellant, you then have the problem with preventing the flame front from going back the fuel feed pipes to the tanks, especially at ignition. Also, remember that the feed pressure of the fuel must be higher than the chamber pressure, requiring either pumps (complicated), or pressurized tanks (thick walled and heavy). This is one of the reasons (among many) that a liquid fuel motor would actually be heavier than solid for the size and application you are looking at.

it might not work so well at very high compression ratios but might work at lowwer compression ratios wher speeds sub sonic would work for my project
There is no "compression ratio" in a rocket motor - just a chamber pressure. In order to be efficient at all, this has to be at least a couple hundred psi, and the exhaust velocity must be supersonic. This eliminates any form of your proposed "tin can example."

RE:ghost
I expect a thin tin motor not to have high compression and therfore low thrust or even no thrust
Actually, it probably is running a chamber pressure at just barely above ambient, and it has an almost complete lack of anything resembling a nozzle. Not only is it a very rudimentary concept demonstrator, it is also not really scalable to anything usable at all.

its the interesting possibilty to start with the more easy solution and gradualy beef it up and gradualy increase fuel rates and compression rates to incremently find suffient power
What you don't seem to understand is that rockets are not jets, and that any decent liquid fueled design simply can't be infinitely scaled. They must run at a certain minimum to work, and if you start below that minimum or attempt to slowly build them up, it simply will not work. Regardless of what may seem intuitive, they simply do not work that way. Also, you need a nozzle specifically optimized for the flow rates and pressures you would like to work at, which is impossible for a "slow ramp up."

RE:Art Upton

Oh yeah these guys get 30mph plus
but first you need a montian and then 30mph plus winds

no wind no speed no mountian no speed

rocket reactor will hopefully work every place
True. Especially if it is a commercial solid motor and simple ignition circuit, and not some fiddly, homebuilt, inefficient liquid motor.

keep you guys posted

JATO

I am looking forward to seeing this - I hope you get it to work, but I don't see that happening with anything but standard solid fuel motors.
 
This is the famous vidio of the B-29 with X-1 rocket plane which is released
after gliding down low a rocket motor then make the x1 rocket plane climb rapidly back up to several hundred feet
I presume it uses solid fuel rocket motor of some 6KG plus

https://www.youtube.com/watch?v=GtIL_VjBUGo

enjoy

This is if you want to do a single shot solution interesting and much easier to do than Liquid fuel solution mono shot or relightable versions

However if i finaly decide to do solid fuel solutions it will only be when I have ensured 100% that there is no realistic possibilty to do it in liquid fuel
So i regret i will continue for some time to unearth all the info there exists

The early rockets 1926 were LOX and alcohol whatever so if they could pull it off then now it is 2008 seems logical can be done today

link to goddards early rockets stuff
https://www.nasm.si.edu/research/dsh/artifacts/RM-RHG1926.htm

I am going to re read everthing from this site to see which part of the eqasions can allow the possible use of Liquid fuel with a plane

They supply all the information on how to build a Liquid fueled rocket

https://www.risacher.org/rocket/

The down side to following their solution is it will use LOX and some sort of fuel and I was hoping to avoid complication of LOX

I will run the numbers again to see if it can be done light weight eneogh using facts that there will be no cooling and short three second runs

cjl said:
If it is preoxygenated and volatile enough to be used as an uncatalyzed monopropellant, you then have the problem with preventing the flame front from going back the fuel feed pipes to the tanks, especially at ignition. Also, remember that the feed pressure of the fuel must be higher than the chamber pressure, requiring either pumps (complicated), or pressurized tanks (thick walled and heavy). This is one of the reasons (among many) that a liquid fuel motor would actually be heavier than solid for the size and application you are looking at.

This information seems to be more inline with a good reason why the project wont work

I will study this issue the most as it makes a lot of sense


"preventing the flame front from going back the fuel feed pipes to the tanks, especially at ignition"

This is problem I hadnt figured on

My first instinct is that methanol a fuel where there is half the molicule is oxegen so it is a highly oxegenated fuel would have similar issues but they cracked that problem but there might be a limit that would possibly explain this problem

All reasearch into nitromethane a highly oxegenated fuel capable to be a monopropelant shows the intitial reasearch in the late 1948 to early fivetys that it was abandoned due to the slower speeds coming out the nozzle compared to other fuels but there might also have been a flame front issue they neglected to mention.

This does mean that pre oxegenating fuel even without the other issues will probably slide down the list of possibilties for now

"remember that the feed pressure of the fuel must be higher than the chamber pressure, ......requiring either pumps (complicated)......"


My preference is to take advantage of the incredible exponental advances in electric power with incredibly small powerfull electric motors and light weight batteries meaning there might exist the possibilty to pump fuel at pressures not imagined even three years ago
Now it is possible the pumps might still not be up to eneogh power but experments in pumps will indicate this good bad or indifferent.

Even if i develop a motor that is bigger i will just have to make a bigger plane but my preference is to try to start smaller and as such cheaper

Also I might make a heavy weight version that is a static model ground based motor and then when the problems are sorted get a fiend of mine in eastern europe to rattle up the final version , but that version might cost me 1000 euros $1200 to be made so I dont expect it to be super cheap but I realy dont think or hope $10,000 is nessary.


Any way i will start to go with a solution mathamaticaly that is LOX version with methanol and high 60% nitromethane mix as that ignites with simple model aircraft glow plugs as that is a fairly standard high performace model fuel

I can look into using liquid CO2 to be pressure for tanks if the electric pump idea is too heavy or unable to supply the pumping power

I shall also re-download all the relvant stuff from armadilloaerospace who are the most up to date on the net with working fairly small liquid fueled rockets to see if there is info I didnt pick up
This link is from the whole history of the archives and is the type of page with lots of info for biprop motor

https://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=306

and the vidio from this page is interesting for a BiProp

https://media.armadilloaerospace.com/2005_06_06/throttledBiprop.mpg

He has also made succesful motors without a closed nozzle exit and with less pressures less power and this supplys sub sonic exit speeds so making the design simpler and less likely to break with hard starts

Lots of realy good info there to inspire wanna be liquid fuel modelers

I will be busy with work for this month so lack of response is not lack of interest its lack of time working to save money up for modeling projects

JATO
 
I haven't waded through all the posts so I apologize if this is too off base and/or has been covered.

First, unless you're going to put in a lot of time and money, liquids are out of reach. The only cheap liquid amateur rocket I've ever seen had a questionable track record.

Pointing to what companies like Armadillo are doing probably don't apply much. A better source might be Paul Breed's work https://unreasonablerocket.blogspot.com/ He might share a lot of info including his investment in the project.

The amateur groups like the RRS and Chemroc should be a better source of info than TRF as you'll find more people who have worked on such projects.
 
JATO, there's a more fundamental point I think you're missing. If there was a way of creating an ultra-cheap, relightable, very long burn motor, do you not think we'd be using them ourselves?

If you think we only use solids to get rid of our excess $$$, then you're wrong there too. Most of us have wives :)
 
If he thinks he is going to save money, wait until he looks into the catalysts he is going to need. Platinum group metals aren't exactly cheap...
 
Re:rstaff3
"Paul Breed's work https://unreasonablerocket.blogspot.com/ "

Excellent link with lots of really good ideas
He figures plastic soda pop bottles can hold LOX so saving weight and costs

Lots of bad news about valve issue with LOX not good

Re:SCE to AUX
"Platinum group metals aren't exactly cheap..."

I was hoping to scavenge of catalyst converter of a second hand automobile exhaust pipe


Any way I still haven't found out what type of metals and alloys etc are needed to do catalyst for N2O and where they are sold and how much I need for this project


RE:init 6

Most of us have wives:surprised:

EERR I am of the road runner fast runner derivative type BEEP BEEP and gone so that"s that issue solved leaving a few more funds for rockets of any sort size or shape


https://home.total.net/~launch/
This is a off the shelf kit sub $1000 dollar 26KG push Liquid rocket but you need 50% H2O2 hydrogen peroxide and to get flying rocketry style where H2O2 is cheap and available would cost around less than $10 a launch


I could simply redouble my efforts to get H2O2 make lots of waves pay extra costs fill in umpteen police and HAZAMAT forms in triplicate store it at secure lock up whatever but I would still have lots of issues not least of them being I would have problems every time I change to a new country of which I tend to do every year(fast runner )

Assuming I built a plane large enough to strap this beast onto a large deltas with a large glow motor prop driven with in-flight start up system for propeller and fold up prop solutions for when the Reactor motor started I would have a plane of about 15KG with a 7 KG reactor motor on top

The cost if that goes wrong and does a CATO would be a bit steep
I would have to go to much more expense on the aircraft as speeds would probably exceed 300MPH sub 400 Mph and be similar in costs to Model jets where they use 25KG turbines and these without engines of $8000 tend to cost more than $4000 just for the plane

Also in most Europe where I hang out exceeding 7kg in a model plane moves you into a special catogry for all sorts of stuff from ATC clearance issues to more rules and regulations limiting the amount of times it would be possible to fly
Staying sub 7KG is a whole lot easier in general if you can

specs on SS67B-3 liquid fuel rocket kit

Thrust: 260 Newtons (57.2 lbs)
Burn : 8.5 seconds
Total Impulse: 2210Ns
Chamber temperature: 450 C (842 F)
Chamber pressure: 200 psi
Nozzle area ratio(exit/throat):2.62:1
Exit gas velocity: Mach 2.4
Fuel: Super unleaded gasoline
Oxidizer: 50% Hydrogen Peroxide
Estimated altitude: >5000 ft.
Dry weight: 4.60 kg (10.12 lbs) (including nose cone, parachute, fins)
Loaded weight: 7.1 kg (15.62 lbs)

Ratio about 3.6 :1 power ratio and fuel is 1/3 of wet AUW

A mathamatical guestimate SWAG scientific wild asses guess is scaling down the SS67B-3 liquid fuel rocket kit from 7.1 kg (15.62 lbs)wet AUW is that 1/3 of the weight is fuel

I am fully aware that scaling wont be so linear
Simple( non real world) this imply's a IKg wet AUW Motor weight if scaled down would equal 3.6KGs of push

A little bigger tanks from 300 grams to say 400 or 20% bigger would return 4 runs of 3 seconds or one run of 12 seconds

Assuming i left out the gasoline flame part and gasoline burning components and tanks ignition burners etc and went for mono prop solution I could probably get 600 grams of fuel to the same thing and save some weight without the complicated flame issues

So assuming with scaling down that instead of a scaled down 700 gram motor empty weight it needed to be say 1400 grams for scale down issues and I binned the flame part at say 600 grams of that motor we are left with a SWAG estimate for motor of 800 grams

800 gram motor and 600 gram fuel would be SWAG 1400 gram auw for this motor

At this stage the rocket culture kicks in and state correctly tnat its a useless low ratio motor of less than 4:1 push and therefore for a rocket guy a useless project

I would have a model plane take off AUW wet weight of say 2kg but less for landing weight 1.4kg dry weight which is tolerable but I would hope to be better than that with other fuel solutions or maybe accept lesser run times or less push maybe 3KG



For me it does the job except i cant get the fuel H2O2 so easy so probably better to find a more easy fuel

Also this project done in H2O2 would not be very benifitial to the modeling community that may wish to have similar solutions for model cars or boats or rocketry

A small not so expensive sub $1500 multi light up liquid fuel solution might suit all sorts of modelers and could serve for larger rocketry projects as side thrusters whatever so its important that if i derive a solution the fuel and oxidizer is easy to obtain

The list that fit that bill the most easy is N2O. nitromethane .methanol, adulterated ethanol (85% ethanol 15% methanol) gasoline diesel

The next level of complexity for fuels and oxidizers might be LOX ,H2O2 hydrogen peroxide (50% or 80% or 90% or 98%) and mayby other strange variations like KNO3 (saltpetre) and nitogen percolates

A pure version of Nitromethane mono prop would be ideal but the research shows issues of high pressures and serious ignition problems and it would have extra power and use a lot less fuel if some few parts of oxygen were to be supplied

the last reference i can find to nitromethane rockets was in 1947 from records of that era where they changed over to gasoline or Ethanol or other Liquid fuels

Solutions I have in theory is it might requre running a small glow fuel motor like 1cc cox and attaching a way over sized tuned pipe exhaust system from motor like 25cc engine and inject in 99%pure nitromethane and 1% methanol into the hot exhaust chamber and hopefully that would ignite and extra air from unburnt glow motor would help out but forward flame might burn out tiny glow motor not sure
Possibly using nitos gas injected into the same system might help combustion

Alternatively block of the end of a tuned exhaust pipe and put in a glow plug inject nitromethane and try that out mayby include N2O

if a pure nitro motor runs that would benefit a lot of modelers where 99% pure nitromethane supplys exist in big cities like paris or berlin but a problem for out of the beaten track


A combination fuel of 60% nitromethane and 40%methanol would help out a lot more costing a lot less and being more easy to obtain similar with 20% oil lubrication from high performance glow fuels and hopefully the oil would burn up a bit or just fall out the pipe and not gum things up


As the engine run times would be short some three second hopefully no cooling would be required and repeat light up after 30 seconds the motor will have cooled down enough to do repeat burns

Any way got to go to work so will keep in contact and check out all those links you supply


JATO
 
hokkyokusei

"You should probably speak to someone who actually owns one."

I sorta did talked to guy who made the kit from plans a few years back when H2O2 was easy to get the good old days 10 years ago

It was nearly impossible to get gasoline to light in the middle of a water shower but he devised a way with acytalline torch welding gear which is possible on the ground but not for airborne project and got some fairly good flights not 5000 feet but close 1000 feet but most were mono prop

Parachute failure was a big issue and killed the rocket and the project

But I am all ears for extra info as I can never get to much info

on this site at the bottom of this page photos of small Liquid bi prop thrusters
https://www.aeroconsystems.com/motors/index.htm

anybody know what the story is with those


some new interesting sphere containers but link
https://www.aeroconsystems.com/plumbing/bottles.htm

Catalina/Parker 20oz bottle - $20 (black on bottom left) is interesting



JATO
 
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