Verge Posted August 23, 2011 Posted August 23, 2011 (edited) Hey everyone, Does anyone know the ideal ratio for rockets?What I mean to say is the Diameter and height of the tube.The rocket is not supposed to carry anything just have the best performance as in longest flight and decent thrust with minimal loss.I was thinking along the line of 1:3 were the 1 is the diameter.When you list the diameter please don't forget to list the nozzle hole size. Edit:I forgot to say when you list the ratio specify if its core or end burners. Edited August 23, 2011 by Verge
THEONE Posted August 23, 2011 Posted August 23, 2011 (edited) Everything dependes to each another... nozzle throat, core, core length, burning rate of the proppelant, how much pressure your casing accept... Edited August 23, 2011 by THEONE
Verge Posted August 23, 2011 Author Posted August 23, 2011 (edited) Everything dependes to each another... nozzle throat, core, core length, burning rate of the proppelant, how much pressure your casing accept... The casing is no prob I just need somewhere to start.I know it was to General but It was the only way I could say it.nm Edited August 23, 2011 by Verge
THEONE Posted August 23, 2011 Posted August 23, 2011 What your fuel will be and your ID of your casing
dagabu Posted August 23, 2011 Posted August 23, 2011 There is really no "best" answer for this question, the long winded screamers are by far the longest flying rockets I have timed with strobe rockets coming in second. Two stage rockets can kill the single stage rockets and with an end burner sustainer with a whistle booster, you can almost double the flight time. There were several 2" ID whistle rockets with a (2:1 ratio) 4" long casing that I found Friday morning at PGI as well as several 10" long 3/4" ID motors (the tops were shredded in most cases) which is about 13.66:1 ratio. Traditionally, it is 10:1 for BP motors. -dag
Verge Posted August 23, 2011 Author Posted August 23, 2011 ID stands for in diameter right?And the fuel is BP though I might try aluminum,kno3,sulfur.Either way I probably just stick with the 10:1 ratio.
THEONE Posted August 23, 2011 Posted August 23, 2011 The longest flight i have seen http://www.youtube.com/watch?v=3vDBSByx7YY
dagabu Posted August 23, 2011 Posted August 23, 2011 What crappy stick mounting!! I have seen 20-25 second powered flights using phenolic tubes. -dag
californiapyro Posted August 23, 2011 Posted August 23, 2011 (edited) hey, what's the fuel for long winded screamers? i know it's a whistle, but in what ratios Edited August 23, 2011 by californiapyro
dan999ification Posted August 23, 2011 Posted August 23, 2011 ID stands for in diameter right?And the fuel is BP though I might try aluminum,kno3,sulfur.Either way I probably just stick with the 10:1 ratio. id is internal diameter do not try to make rocket fuel with kn03 s al unless you discuss the exact ratio and procedure first this is not safe, one of the easiest ways to injure yourself.there is no exact answer like dag said.endburners typically are easier to tailor time wise, more fuel= longer burn to a point too much will come back down as the internal volume decreases so does the pressure, and with it the thrust. depending on how high you want it determines how much fuel yu put in.ive made motors with an inch of fuel to 2.5 or more the ratio varies [baring in mind these are ten mm endburners] with 2mm nozzle,i think bp endburners would be hard to beat with minimal chems and tooling. dan.
dan999ification Posted August 23, 2011 Posted August 23, 2011 What crappy stick mounting!! I have seen 20-25 second powered flights using phenolic tubes. -dag i have seen cored bp rockets stay up for more than 40 secs dan.
THEONE Posted August 23, 2011 Posted August 23, 2011 i have seen cored bp rockets stay up for more than 40 secs dan. Have you got a video ?
r1dermon Posted August 24, 2011 Posted August 24, 2011 ID stands for in diameter right?And the fuel is BP though I might try aluminum,kno3,sulfur.Either way I probably just stick with the 10:1 ratio. this will make a boom. also consider adding a pinch of boric acid into that cocktail. just for safeties sake.
guntoteninfadel Posted August 24, 2011 Posted August 24, 2011 The longest flight i have seen http://www.youtube.c...h?v=3vDBSByx7YY Without being rude..... would it be too much to ask not to use the word "bomb"? Salute would work just as well.
WonderBoy Posted August 24, 2011 Posted August 24, 2011 (edited) Dag were those 2" ID tubes frayed at the top too? And some LWS info can be found here SLD quotebut there are many fuel and spindle options. Recently I have been really enjoying 2 stage whistles. A medium size core in the booster stage, and a smaller core for the sustainer. Everything pressed to 7000psi OTC, except above the short spindle I press to a much lower psi OTC, so it burns faster and can keep the rocket moving even during the end burn. Edited August 24, 2011 by WonderBoy
dagabu Posted August 24, 2011 Posted August 24, 2011 Nope, some had purple duct tape holding them to the stick and the others had real big fillets of hot glue holding the tubes. There were no shells or reports attached that i could see and the tube ends were cut smooth like they would be from a bandsaw. There were also a whole bunch of 1.5" x 4" as well out there. -dag
dagabu Posted August 24, 2011 Posted August 24, 2011 Dag were those 2" ID tubes frayed at the top too? And some LWS info can be found here SLD quotebut there are many fuel and spindle options. Recently I have been really enjoying 2 stage whistles. A medium size core in the booster stage, and a smaller core for the sustainer. Everything pressed to 7000psi OTC, except above the short spindle I press to a much lower psi OTC, so it burns faster and can keep the rocket moving even during the end burn. I was lucky enough to both see one of those bad-boys up close and then see it fly. Very nice rocket and design! I would love to get more info on that one some day (please?). -dag
dan999ification Posted August 24, 2011 Posted August 24, 2011 Have you got a video ? sure makes for some interesting viewing some dont come down for 4 minutes this is just one example of many on the tube http://youtu.be/mVH-TMi9ixM dan.
dagabu Posted August 24, 2011 Posted August 24, 2011 Right....... 6" PVC, 200 pounds of BP, 20' long stick. I got one in my back pocket. OK, that was not a real comparison in any way to what we do here. -dag
dan999ification Posted August 24, 2011 Posted August 24, 2011 Right....... 6" PVC, 200 pounds of BP, 20' long stick. I got one in my back pocket. OK, that was not a real comparison in any way to what we do here. -dag haha yeah it was just meant as an example to show the size difference in ratios some are short and fat some are long and thin. dan.
allrocketspsl Posted August 24, 2011 Posted August 24, 2011 (edited) Hey everyone, Does anyone know the ideal ratio for rockets?What I mean to say is the Diameter and height of the tube.The rocket is not supposed to carry anything just have the best performance as in longest flight and decent thrust with minimal loss.I was thinking along the line of 1:3 were the 1 is the diameter.When you list the diameter please don't forget to list the nozzle hole size. Edit:I forgot to say when you list the ratio specify if its core or end burners. just thought I would chime in and bloviate some to show you the wide difference in ratios, all my rockets fly on 57/34/9,no your truly confused ,yes!All core bunners! Edited August 24, 2011 by allrocketspsl
guntoteninfadel Posted August 26, 2011 Posted August 26, 2011 Ok, That was ummmm crazy! I dont want to be that close to my 1lb rockets when they fly, lawd jeezus them folks was drinking tea right next to the thing. Glad they didnt cato. AND by the way, whats the deal with the hats on the umbrellas?
WonderBoy Posted August 27, 2011 Posted August 27, 2011 I don't know Dag, that competition STILL isn't over (come on people!), so I don't know if I should divulge all of the details... Just kidding. I can give you more info when I have more time. Were you talking about the 2 stage whistle to BP with 3 break header that I showed you? Or did you actually see one of my 2 stage whistles? I can't remember if I showed you one of those as well.
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