Time between some of his replies is 1 minute. Must just be sitting at PC waiting to answer.
It's at least a sign he's still alive.Even if he is, it's irrelevant.
A belated welcome to the forum. However, statements like this don't fill us with any confidence that you know what you're doing! This dismissive attitude to good advice is, at best, naive; and at worst, very dangerous.As for h2o2, it isn’t that difficult or scary to work with/make (at least compared to rfna). It’s just a vacuum distillation, or if you have a good heat plate you can heat water just under boiling so it rapidly evaporates (won’t decompose h2o2)
Excellent advice!I fly stuff at FAR a decent amount, ....
Chiaverini & Kuo for hybrids, right? I've been looking for a similarly comprehensive treatment dedicated to solids, but no joy.Ignition by John Clark has been mentioned a few times, but it it's an informal history of liquid propellant development in the 50s, not a textbook on engine design. From listening to people that know a lot more about liquids than me, Rocket Propulsion Elements by George Sutton and Design of Liquid Propellant Rocket Engines by Huzel and Huang are both well recommended books about engine design.
Please don't replicate any of Goddard's early designs. Using boil off from your oxidizer tank to pressurize your fuel is more than a little bit sketchy...Of course, if you're really looking to get a start with liquid fueled rockets, right here is a good place to start:
Thanks. I totally could be wrong, but I have done more research on high test h2o2 since I posted and I haven’t seen any evidence it is more or less dangerous than boiling water. Afaik as long as you don’t get it on you it should be fine. I know that storing it is a little more challenging because of not having it decompose and bubble. As for my experience, I think I have said this in other posts, with rocketry, none. However, my current goal (and the goal I would like this post to be about) is to just make a 500-1000 N total impulse engine. It would only be static fired. I also am working on other rocketry projects with commercial motors.A belated welcome to the forum. However, statements like this don't fill us with any confidence that you know what you're doing! This dismissive attitude to good advice is, at best, naive; and at worst, very dangerous.
A number of members have asked about your level of knowledge and rocketry experience up to deciding that you wish to attempt an extremely challenging liquid-fuelled launch. So far, you have not responded with that information. It is hard for us to take dreams like this seriously when you don't take us on your journey.
Be smart, and be safe!
Have you tried Fundamentals of Solid Propellant Combustion? Also Kuo, and similar layout.Chiaverini & Kuo for hybrids, right? I've been looking for a similarly comprehensive treatment dedicated to solids, but no joy.
As has been mentioned, you'll do well to find a commercial source of HTP.Thanks. I totally could be wrong, but I have done more research on high test h2o2 since I posted and I haven’t seen any evidence it is more or less dangerous than boiling water. Afaik as long as you don’t get it on you it should be fine. I know that storing it is a little more challenging because of not having it decompose and bubble. As for my experience, I think I have said this in other posts, with rocketry, none. However, my current goal (and the goal I would like this post to be about) is to just make a 500-1000 N total impulse engine. It would only be static fired. I also am working on other rocketry projects with commercial motors.
As for the reason I’m not using lox is I don’t want to have to do cryo. If anyone has a safer oxidizer then h2o2 that isn’t cryogenic, I would greatly appreciate recommendations
Reading this thread I've been thinking that the OP will be repeating Goddard's work to some extent. He would have the benefit of knowing somewhat in general what the end result would be, it sounds like he is trying to build his own Aerobee-Hi. I can't imagine how long or how many millions of dollars this could take.Please don't replicate any of Goddard's early designs. Using boil off from your oxidizer tank to pressurize your fuel is more than a little bit sketchy...
Thanks so much. I do have one oxidizer option that hasn’t been mentioned. On this site Here it mentions gaseous oxygen. Is this a viable option for non cryo needs, safety, and easiness to storeAs has been mentioned, you'll do well to find a commercial source of HTP.
50%, no probs, but you'll have to concentrate it and that can be dangerous if done incorrectly and/or without good care. And the stabilisers in there might need removal if you're passing through a catalyst pack you wish to reuse.
There have been incidents with it in concentrated form (aside from Subs and Torpedos). Gilmour's (probably the largest current users of it) experienced an incident a few year ago that resulted in no fatalities, but significant fire and damage. That (apparently) was a storage issue.
The other obvious oxidizer is N2O. Again, it has its issues too, but is perhaps the easiest to handle from the choice of it, NA and HTP. LOX is by far the safest to handle in large quantities, but there's the cryo thing.
TP
GOX is pretty normal for a benchtop demonstrator.Thanks so much. I do have one oxidizer option that hasn’t been mentioned. On this site Here it mentions gaseous oxygen. Is this a viable option for non cryo needs, safety, and easiness to store
What is the reason I couldn’t do it at a large ish launch site. Especially if I do it remotely and with not large amounts of fuel. (So the tanks won’t explode). I definitely think at almost all to all sites it would be a no-no with even approaching explosive levels of fuel. But if I used small amounts to at least iterate designs over short periods of time before going through the long process of finding somewhere I could do a larger test. I am fairly sure I couldn’t even do this, but would like it confirmed.Reading this thread I've been thinking that the OP will be repeating Goddard's work to some extent. He would have the benefit of knowing somewhat in general what the end result would be, it sounds like he is trying to build his own Aerobee-Hi. I can't imagine how long or how many millions of dollars this could take.
If worked through methodically, he would have to build a motor, build a test stand, build some instrumentation, then test it. Goddard ended up in the middle of nowhere in New Mexico because he couldn't test even small motors in the more populated area where he lived. That was 100 years ago, it would be even worse today. It would be a pretty monumental effort to build a working motor, that would have to go through numerous iterations. He couldn't build the actual rocket and start thinking about where to launch it and get permits and so forth.
While I think it would be fun to develop a real liquid fuel engine, I think it would be a lot more expeditious to build a large hybrid.
Looks good, will have to keep an eye out for a copy.Have you tried Fundamentals of Solid Propellant Combustion? Also Kuo, and similar layout.
*For ground testing*: absolutely! It's not a practical oxidizer for flight due to its density, but for developing a feel for liquids and plumbing and chambers and maybe regen cooling - I would recommend it.Thanks so much. I do have one oxidizer option that hasn’t been mentioned. On this site Here it mentions gaseous oxygen. Is this a viable option for non cryo needs, safety, and easiness to store
That’s all my initial few iterations would be so I’ll look into that. Thanks for confirming.*For ground testing*: absolutely! It's not a practical oxidizer for flight due to its density, but for developing a feel for liquids and plumbing and chambers and maybe regen cooling - I would recommend it.
TP
https://www.propulsionlabs.com.au/Gox_Methanol_Test/Sunday_Hot_Test1.mp4That’s all my initial few iterations would be so I’ll look into that. Thanks for confirming.
I don't know what the practical limitations might be. Goddard's first rocket was relatively small but apparently loud enough that his neighbors didn't like it. There are parts of the US that have a whole lot of nothing and if you could find a landowner that would allow it you could do tests there. Public land such as BLM might be a different matter because they probably have regulations against it. To actually launch a big rocket would be even harder because now you have to get FAA clearance and apparently lots of deserts have restricted airspace above them.What is the reason I couldn’t do it at a large ish launch site.
What is the reason I couldn’t do it at a large ish launch site. Especially if I do it remotely and with not large amounts of fuel.
No NAR club will let you anywhere near their site. The insurance doesn't cover this activity, for one thing.
TRA, depends on the club, I guess. But it seems unlikely.
I would assume a static fire of a rocket engine may be ruled differently than a launch because there isn’t the risk of the engine failing.
I fly stuff at FAR a decent amount, so I've seen a good number of liquid rocket projects. I also hang out online with several people who work on liquids both in industry and as hobby projects.
Any spaceshot attempt is an extremely ambitious project. Adding on a liquid engine is also going to significantly increase complexity. The highest altitude achieved by an amateur group flying a liquid rocket engine that I know of is UCLA, and they only hit 22,000 feet, or about 6.7 km. There are other university groups with plans to fly higher, most notably Space Concordia with a 40 foot tall behemoth of a rocket intended to break the Karman line, but they have yet to fly.
I would strongly suggest that you do a lot more research before committing to any specific design requirements like final mass or propellant selection. Building some conventional high power rockets and getting your certs won't help too much with the liquid engine part, but will be a great way to learn about every other part of the rocket, from stability to recovery.
Ignition by John Clark has been mentioned a few times, but it it's an informal history of liquid propellant development in the 50s, not a textbook on engine design. From listening to people that know a lot more about liquids than me, Rocket Propulsion Elements by George Sutton and Design of Liquid Propellant Rocket Engines by Huzel and Huang are both well recommended books about engine design.
Finally, I'd strongly suggest taking a look at what's worked for amateur liquid rockets. Most groups are using LOX for their oxidizer, with several different fuels. Half Cat Rocketry has been doing some amazing work with low cost rockets using nitrous oxide and alcohol. You'll find very few people using RFNA or H2O2 in this day and age.
Please take things slowly and make realistic goals. A several hundred kilo rocket flying to several hundred kilometers is well outside the scope of anything I'd call amateur. Launching a liquid rocket to space is probably possible, but it would require a group that has significant experience with flying liquid engines on a smaller scale. Please stay safe and find someone who has experience to help you, I've seen some absolutely terrifying "liquid rocket engines" posted online built by teenagers who thought they knew everything.
Yup,At this point, I'm pretty sure we're getting trolled... no pics of what he's "working on".
Not a troll, just someone who has an ambitious idea and no idea of the actual complexity involved. You see them a lot more in other rocketry communities that young people will tend to find before TRF. I typically see them either trying to build a TVC rocket, after seeing a few BPS.space videos, or making super sketchy sugar motors after seeing the a YouTube video with absolutely horrible instructions on how to build them.Yup,
A troll. I wouldn't mind if it was a University or College based group of engineer students, Phd's or otherwise doing this as they would follow the rules to launch from an appropriate "gubbermint" site over the ocean into "no where". As such, this troll just started posting B.S. about a "liquid" motor that yanked a lot of legitimate fliers chains who follow established flying rules with APCP motors!!!
If legitimate, it would have listed the school(s), professor(s) and skilled rocketeers who were mentoring such students to achieve such a task with a liquid rocket propelled motor. Pure B.S. as far as I'm concerned. Kurt Savegnago
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