[AR] HNF issues

  • From: "John Dom" <johndom@xxxxxxxxx>
  • To: <arocket@xxxxxxxxxxxxx>
  • Date: Thu, 3 Dec 2015 00:33:20 +0100

The name Louwers is familiar dating from his amateur rocketeer days. I doubt I
ever met him in The Netherlands. Bottled aqueous hydrazine N2H4 solution smells
like ammonia.
jd

-----Original Message-----
From: arocket-bounce@xxxxxxxxxxxxx [mailto:arocket-bounce@xxxxxxxxxxxxx] On
Behalf Of Anthony Cesaroni
Sent: woensdag 2 december 2015 17:11
To: arocket@xxxxxxxxxxxxx
Subject: [AR] Re: HNF issues

That would be http://www.appbv.nl/index.asp

Our director of propulsion worked there before joining our company. He did his
thesis on the combustion of HNF and it makes a fine coffee table book.

The issue with HNF tends to be compatibility with many traditional propellant
constituents as well as elevated temperatures above 60 C. We solved many of the
compatibility issues by coating the HNF with functional nitrocellulose then
cross-linking it in situ. This also greatly improves the mechanical properties
of the finished propellant.

HNF is produced by an exothermic crystallization reaction of hydrazine and
trinitromethane, often in the presence of ultrasound. When it decomposes, it
releases hydrazine and as strange as it sounds, it's very incompatible with
hydrazine so it "runs away". Slowly or quickly depending on the conditions.
That's how I found out what hydrazine smells like. :-). Conversely, Dr.
Louwers analyzed some neat HNF that had been stored in a unconditioned magazine
at China Lake for over 30 years and it was perfectly fine. The other challenge
is it's very high burn rate exponent but there are ways to deal with that too.

It's also incredibly expensive ($8000~$10,000 kg. depending on the grade) but
large scale production would reduce the costs enough to justify the performance
advantages.

Aside from that, its fine.

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 John Dom
Sent: Wednesday, December 02, 2015 9:28 AM
To: arocket@xxxxxxxxxxxxx
Subject: [AR] HNF issues

On Behalf Of Anthony Cesaroni 12022015

Describes Hydrazinium Nitroforomate (HNF) perfectly... Unfortunately it like
other magic propellants, has issues.

Issues like?

(I remember a factory was built to produce HNF in the Netherlands, close to our
border. Gas generators for ESA I guess. I did not follow this up further).

jd





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