[AR] Re: [AR] Re: [AR] Re: [AR] Re: [AR] Re: [AR] Re: “Transitioning space propulsion to a nitrous-based industry standard”
- From: Alexander Mikhailov <alexander.mikhailov@xxxxxxxxx>
- To: arocket@xxxxxxxxxxxxx
- Date: Mon, 10 Apr 2023 19:28:43 +0000
I can’t recall any straight alcohol being hypergolic with HTP.
FIrst, decompose HTP :) , the steam-oxygen results are hot enough to
ignite a wide range of organic fuels.
Second, dissolve NH4SCN - ammonium thiocyanate - in an alcohol, it's
hypergolic with liquid peroxide, even low concentration. Serge Pipko
run some experiments in 2005...
On 4/10/23, Bill Bruner <bill@xxxxxxxxxx> wrote:
I'm researching that piston pump project, and can't find anything from
LLNL after approx. 2005 :( . Did they stop working on that?
Yes. The Principal Investigator has long since retired and his Astrid
rocket & piston pump fed engine are on display in a non-public hallway.
If you were willing to pay, you could call the partnership office and
license the technology. But that's the only way I can think of to get
access to it.
https://www.osti.gov/biblio/6730431
Bill
On Tue, Apr 4, 2023, 4:10 PM Alexander Mikhailov <
alexander.mikhailov@xxxxxxxxx> wrote:
(The LLNL piston-pump guys, who switched from hydrazine to peroxide for
their experimental work, were surprised and impressed by just how much
easier it made everything -- for example, they could do quick tests on
the
lab bench, instead of having to go out to a hazmat test site every time.)
I'm researching that piston pump project, and can't find anything from
LLNL after approx. 2005 :( . Did they stop working on that? Where's
that information about comparative simplicity of HTP vs. N2H4 comes
from?
Alex
On 4/4/23, Matthew JL <prmattjl@xxxxxxxxx> wrote:
Why not hydrogen peroxide in monoprop or one of the various alcohols
that
it’s hypergolic with?
On Tue, Apr 4, 2023 at 5:47 PM Henry Spencer <hspencer@xxxxxxxxxxxxx>
wrote:
On Tue, 4 Apr 2023, Norman Yarvin wrote:
...The industry has moved away from hypergolics for launch,
but not for precise orbital maneuvering, likely because it's a big
advantage to be able to just release a blip of fuel and oxidizer and
know they will combust immediately: no having to wait for a torch
igniter to fire up.
For precise orbital maneuvering, there's no reason why you need
anything
more than a torch igniter! At least one of the innumerable proposals
for
a nontoxic-propellants Shuttle RCS/OMS system envisioned eliminating
the
RCS vernier thrusters in favor of igniter-only operation of the main
RCS
thrusters.
Setting that aside, bear in mind that torch igniters don't necessarily
have to add a lot of complexity or delay. The Apollo SM/LM RCS
engines
used a "preigniter" scheme, with the plumbing arranged so that
propellant
flow through the main valves reached the preigniter chamber first, so
it
would light (hypergolically) and pressurize the main chamber before
flow
reached the main injector, minimizing (hypergolic) ignition delays
there.
You could presumably do the same thing with a spark-ignited torch, so
it
would still need the spark system but wouldn't have its own valves
etc.
(That does lose one advantage of separate valves: verifying torch
ignition before committing to main-chamber flow, so the control system
can
abort startup if the igniter malfunctions.)
Henry
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- » [AR] Re: [AR] Re: [AR] Re: [AR] Re: [AR] Re: [AR] Re: âTransitioning space propulsion to a nitrous-based industry standardâ - Alexander Mikhailov