3 Nov 2003 03:29
Armadillo nov 1
John Carmack <johnc <at> idsoftware.com>
2003-11-03 02:29:54 GMT
2003-11-03 02:29:54 GMT
http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=230
3 Nov 2003 06:06
Re: Armadillo nov 1
Alex Fraser <beatnic <at> comcast.net>
2003-11-03 05:06:23 GMT
2003-11-03 05:06:23 GMT
If you bolt a plate to the table of your CNC mill and bolt the plasma torch to a bar on the mill head, you can use the CNC to make precision cuts. Cover the mill's important parts with sheilding, to catch bits of slag. -- -- >>>>>>>>>>>>>>>>----<<<<<<<<<<<<<<<<< ........ Alex Fraser N3DER ......... ......... beatnic <at> comcast.net ....... [~]_>^</\-[~]_>^</\-[~]_>^</\-[~]_>^<
3 Nov 2003 21:00
Next Meeting ...
Michael Wallis <mwallis <at> Ceres.wallis.com>
2003-11-03 20:00:01 GMT
2003-11-03 20:00:01 GMT
The next meeting of the Experimental Rocket Propulsion Society will be
held this THURSDAY evening at the Bowers Denny's starting at 8:00pm.
Items for meeting #271 (06 Nov 2003):
- Admin Teams
- CMT
- Documentation
- IT
- Liaisons
- Logistics
- PAO
- Treasurer
- Development Teams
- Chief Scientist
- Flight Controls
- Propellants/Sparger/FF
- Regulatory Affairs
- Safety
- Testing
- Project Status
- Composites
- GizmoCopter
- KISS
- POGO
- SmartFlight
- Spike
The address is:
(Continue reading)
4 Nov 2003 22:45
H2O2/Kerosene burn method
Henrik Schultz <henrik <at> schultz-software.dk>
2003-11-04 21:45:14 GMT
2003-11-04 21:45:14 GMT
Hiya All, I intend to make some experiments with 85% H2O2, and a kerosene derivate (most probably JP-4). I am however confused as to the best way to burn this mix, as it seems as there are different routes one can take. Method 1) One source (isn't it the ERPS site?) mentions something along the line of "Catalytically decompose the H2O2 and then inject kerosene in the hot gas stream, which essentially doubles the Isp." This is simple, in the sense that it alleviates the need for an igniter. However, conceptually it doesn't match any methods I've seen described in Sutton or Huzel/Huang (perhaps except for the gas/liquid jet injectors). Method 2) Another source works with traditional injection and impinging the propellants into the combustion chamber, which seems to work under the assumption that heat is already present in the chamber to get the reaction going (igniter). I have a strong preference for this, as it allows us to use stabilized H2O2. Here are my questions: Has anyone of you ever tried method 2) ? Am I right in assuming that method 2) is self-sustaining, given a properly sized combustion chamber, i.e. will the H2O2 at 85% produce enough heat to both vaporize the water content as well as ignite the kerosene? Thanks for any input you can provide! Cheers - Henrik(Continue reading)
4 Nov 2003 23:05
Re: H2O2/Kerosene burn method
David Weinshenker <daze39 <at> earthlink.net>
2003-11-04 22:05:28 GMT
2003-11-04 22:05:28 GMT
Henrik Schultz wrote: > > Hiya All, > > I intend to make some experiments with 85% H2O2, and a kerosene derivate > (most probably JP-4). I am however confused as to the best way to burn this > mix, as it seems as there are different routes one can take. > > Method 1) One source (isn't it the ERPS site?) mentions something along the > line of "Catalytically decompose the H2O2 and then inject kerosene in the > hot gas stream, which essentially doubles the Isp." This is simple, in the > sense that it alleviates the need for an igniter. However, conceptually it > doesn't match any methods I've seen described in Sutton or Huzel/Huang > (perhaps except for the gas/liquid jet injectors). > > Method 2) Another source works with traditional injection and impinging the > propellants into the combustion chamber, which seems to work under the > assumption that heat is already present in the chamber to get the reaction > going (igniter). I have a strong preference for this, as it allows us to use > stabilized H2O2. > > Here are my questions: > > Has anyone of you ever tried method 2) ? > > Am I right in assuming that method 2) is self-sustaining, given a properly > sized combustion chamber, i.e. will the H2O2 at 85% produce enough heat to > both vaporize the water content as well as ignite the kerosene? > > Thanks for any input you can provide!(Continue reading)
4 Nov 2003 23:54
Re: H2O2/Kerosene burn method
Doug Jones <djones <at> xcor.com>
2003-11-04 22:54:53 GMT
2003-11-04 22:54:53 GMT
David Weinshenker wrote: > Henrik Schultz wrote: > >>Hiya All, >> >>I intend to make some experiments with 85% H2O2, and a kerosene derivate >>(most probably JP-4). I am however confused as to the best way to burn this >>mix, as it seems as there are different routes one can take. >> >>Method 1) One source (isn't it the ERPS site?) mentions something along the >>line of "Catalytically decompose the H2O2 and then inject kerosene in the >>hot gas stream, which essentially doubles the Isp." This is simple, in the >>sense that it alleviates the need for an igniter. However, conceptually it >>doesn't match any methods I've seen described in Sutton or Huzel/Huang >>(perhaps except for the gas/liquid jet injectors). >> >>Method 2) Another source works with traditional injection and impinging the >>propellants into the combustion chamber, which seems to work under the >>assumption that heat is already present in the chamber to get the reaction >>going (igniter). I have a strong preference for this, as it allows us to use >>stabilized H2O2. >> >>Here are my questions: >> >>Has anyone of you ever tried method 2) ? >> >>Am I right in assuming that method 2) is self-sustaining, given a properly >>sized combustion chamber, i.e. will the H2O2 at 85% produce enough heat to >>both vaporize the water content as well as ignite the kerosene?(Continue reading)
5 Nov 2003 00:22
Re: H2O2/Kerosene burn method
Henry Spencer <henry <at> spsystems.net>
2003-11-04 23:22:36 GMT
2003-11-04 23:22:36 GMT
On Tue, 4 Nov 2003, Henrik Schultz wrote:
> Method 1) One source (isn't it the ERPS site?) mentions something along the
> line of "Catalytically decompose the H2O2 and then inject kerosene in the
> hot gas stream, which essentially doubles the Isp." This is simple, in the
> sense that it alleviates the need for an igniter. However, conceptually it
> doesn't match any methods I've seen described in Sutton or Huzel/Huang
> (perhaps except for the gas/liquid jet injectors).
That's right, it doesn't. H/H and (to a slightly lesser extent) Sutton
are books by Rocketdyne guys about Rocketdyne's approach to rocket
engines. If Rocketdyne never did it, it's probably not in those books.
Rocketdyne has done a lot of things, but they've never done catalyzed-
peroxide engines much.
Bragg's "Rocket Engines" is well worth having for an alternate point of
view, although like so many other books in this field, it's long out of
print and a bit hard to find.
> Am I right in assuming that method 2) is self-sustaining, given a properly
> sized combustion chamber, i.e. will the H2O2 at 85% produce enough heat to
> both vaporize the water content as well as ignite the kerosene?
It's feasible, although there is plenty of room for trouble with ignition,
stability, and performance. (In particular, non-hypergolic liquid-liquid
combinations using immiscible liquids seem to be somewhat prone to
ignition problems, perhaps because the liquids *cannot* mix as liquids.
The more energetic the igniter, the better.)
Henry Spencer
henry <at> spsystems.net
(Continue reading)
5 Nov 2003 00:28
Re: H2O2/Kerosene burn method
Henry Spencer <henry <at> spsystems.net>
2003-11-04 23:28:17 GMT
2003-11-04 23:28:17 GMT
I wrote:
> ...non-hypergolic liquid-liquid
> combinations using immiscible liquids seem to be somewhat prone to
> ignition problems...
Small qualification: I should have said "storable" somewhere in there.
When at least one of the liquids is cryogenic, there's usually enough heat
around to turn at least some of it to a gas, and that seems to greatly
reduce the problems.
Henry Spencer
henry <at> spsystems.net
5 Nov 2003 09:44
Re: H2O2/Kerosene burn method
John Carmack <johnc <at> idsoftware.com>
2003-11-05 08:44:19 GMT
2003-11-05 08:44:19 GMT
At 10:45 PM 11/4/2003 +0100, you wrote: >Hiya All, > >I intend to make some experiments with 85% H2O2, and a kerosene derivate >(most probably JP-4). I am however confused as to the best way to burn this >mix, as it seems as there are different routes one can take. > >Method 1) One source (isn't it the ERPS site?) mentions something along the >line of "Catalytically decompose the H2O2 and then inject kerosene in the >hot gas stream, which essentially doubles the Isp." This is simple, in the >sense that it alleviates the need for an igniter. However, conceptually it >doesn't match any methods I've seen described in Sutton or Huzel/Huang >(perhaps except for the gas/liquid jet injectors). We did several dozen tests with this method, and it has a LOT to reccomend it. We put quite a bit of pictures and detail in the armadillo updates on this last year, and overall, it worked much better and easier than we expected. Smooth engine starts, no worry about unburned propellant coming out the nozzle (always stop kerosene first, then finish in monoprop mode), and drastically easier injector design when you have very hot gas to mix with a relatively small amount of liquid. The only caution I would make is to do test firings vertically instead of horizontally. The only explosion we have ever had at Armadillo was when we had a horizontal firing engine test that had a stuck kerosene solenoid, allowing kerosene to drain into the catalyst pack, so the next time we fired peroxide into the pack, it all blew up. >Method 2) Another source works with traditional injection and impinging the >propellants into the combustion chamber, which seems to work under the >assumption that heat is already present in the chamber to get the reaction(Continue reading)
5 Nov 2003 10:22
Solvay ultra-pure semiconductor grade
John Carmack <johnc <at> idsoftware.com>
2003-11-05 09:22:39 GMT
2003-11-05 09:22:39 GMT
It looks like Solvay ultra-pure semiconductor grade peroxide is completely unstabilized, and at least as good a spec as rocket grade peroxide. We should be testing some 50% next week, and if it works out, I am going to buy many tons of it. I will report pricing. This may be useful for concentrator work, removing the need for purification. We are making very good progress with the engines now, isolating the important bits and reducing the manufacturing work. After over six months of development, I think we have just about got it. John Carmack
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