Hummm now that is interesting Anthony. Hummmmmm and thanks!
-------- Original Message --------
Subject: [AR] Re: Peltier specifications
From: "Anthony Cesaroni" <acesaroni@xxxxxxxxxxx>
Date: Tue, August 04, 2015 2:31 pm
To: <arocket@xxxxxxxxxxxxx>
Been there done that. It makes your rocket smell like your grandmother's
cedar chest and sublimates causing other issues as well. Having said that,
if you press it with low micron or nano aluminum, it makes for an interesting
fuel grain with interesting ballistic characteristics.
.
Particularly in an “all solid” hybrid.
Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
http://www.cesaronitech.com/
(941) 360-3100 x101 Sarasota
(905) 887-2370 x222 Toronto
-----Original Message-----
From: arocket-bounce@xxxxxxxxxxxxx [mailto:arocket-bounce@xxxxxxxxxxxxx] On
Behalf Of Monroe L. King Jr.
Sent: Tuesday, August 04, 2015 5:18 PM
To: arocket@xxxxxxxxxxxxx
Subject: [AR] Re: Peltier specifications
I wonder if Naphthalene would make a good additive to HTPB hybrid propellant?
It's a white powder (used mostly in mothballs) it sublimates quite easily.
It's a hydrocarbon, perhaps it would help stabilize hybrid combustion?
I know adding AP to the HTPB helps combustion say 5%.
-------- Original Message --------
Subject: [AR] Re: Peltier specifications
From: Bill Claybaugh < <mailto:wclaybaugh2@xxxxxxxxxx>
wclaybaugh2@xxxxxxxxxx>
Date: Tue, August 04, 2015 2:04 pm
To: " <mailto:arocket@xxxxxxxxxxxxx> arocket@xxxxxxxxxxxxx" <
<mailto:arocket@xxxxxxxxxxxxx> arocket@xxxxxxxxxxxxx>
Not really a preburner and not really adding any complexity; the TEA system
was needed for ignition, increasing the size of that tank was all that was
required to eliminate most combustion instability.
I can't speak to other technical solutions; but note that it does not
require all that much heat to vaporize a Lox fog.
Bill
Sent from my Commodore 64
On Aug 4, 2015, at 3:54 PM, Henry Vanderbilt <
<mailto:hvanderbilt@xxxxxxxxxxxxxx> hvanderbilt@xxxxxxxxxxxxxx> wrote:
Interesting. So if I'm understanding this correctly, you're talking
about something like an oxygen-rich preburner to make sure the oxidizer
is thoroughly vaporized as being useful for large hybrids.
Makes sense of what VG might be having methane onboard SS2 for. I'd been
wondering about that.
It sounds like the sort of thing one would come up with after already
committing to large hybrids, then hitting the (apparently fairly typical)
uneven combustion, to make them actually work. If you assume from the
start you'll need some sort of preburner with a separate fuel system, I'd
think large hybrids would lose their lower-parts-count edge over biprops
in the tradeoffs.
On 8/4/2015 11:37 AM, Bill Claybaugh wrote:
Mark:
It seems like an AN & ice water mix could be tailored to your
temperature goals. But why not go to a dry ice cooler and maximum
density: a single pass on a couple of coils should get you what you are
seeking. LN2 is also obviously an answer; both can be had in Mojave.
As Anthony has hinted, you will need a heat source at the head end to
assure the N2O fog is vaporized, otherwise combustion will be rough and
unstable. At Amroc we injected TEA throughout the burn to vaporize the
Lox; I gather VG is using Methane in the SS2 nylon motor.
Bill
Sent from my Commodore 64
On Aug 3, 2015, at 9:33 PM, Mark C Spiegl <
<mailto:mark.spiegl@xxxxxxxxx> mark.spiegl@xxxxxxxxx> wrote:
Wow... Im out of the office for a day and my inbox is full! :-)
Anyway.. Anyone who has followed my hybrid projects knows Im a fan of
high density Nitrous. Im looking to cool 20-50 lbs of Nitrous to 25-ish
degF.
Goals:
(1) Flashing liquid to vapor to chill Nitrous is fine in a motor
burning 10-20 lbs of Nitrous. Much above 20lbs (esp in the desert),
flashing liquid to gas becomes impractical. I would like to start a
little closer to my target temperature of 22 degF. The Peltier,
Stirling Cooler, or whatever would chill the supply tank, not the
rocket tank.
I know ice is a quick-and-dirty answer, but I would like something a
little more elegant and deterministic. Bags of ice aren't a great
answer at FAR or Blackrock.
(2) I have had trouble igniting high density Nitrous in warm weather.
Cold weather is no problem. I cannot prove what is happening, but I
suspect temperature gradients in the long thin Nitrous tank are causing
the problem. If the Nitrous is 22 degF at the top of the tank, it may
be much much colder at the injector. Supplying Nitrous close to the
final temperature should help mitigate this problem, if Im correct.
A related question: Any simple ways to equalize temperature between
the top and bottom of the rocket's oxidizer tank???
--MCS
(Im an EE kind of person so my solutions tend to feel like
electronics... ie Peltiers)