Ken,
I know exactly where you’re coming from, but PPG sims higher than PB AND I can
vouch that the *measured* numbers correlate very very closely to what the sims
say.
Why is PPG higher? I honestly don’t know. It should be lower. Its enthalpy
of formation is lower (which it should be). All I can think is that the
formation energy of the exhaust of a PPG propellant is much lower than that of
a comparable PB propellant, but I don’t know why there would be such a
difference.
Troy
From: arocket-bounce@xxxxxxxxxxxxx [mailto:arocket-bounce@xxxxxxxxxxxxx] On ;
Behalf Of roxanna Mason
Sent: Wednesday, 8 July 2020 5:46 PM
To: arocket@xxxxxxxxxxxxx
Subject: [AR] Re: Making composite APCP in Australia
OK kind of like alcohol and LOx, O/F is much lower than hydrocarbons like
kerosene plus the exhaust is transparent studded with shock diamonds. So is the
ISP somewhat lower than PB for similar reasons?
Ken
On Tue, Jul 7, 2020 at 10:26 PM Troy Prideaux <troy@xxxxxxxxxxxxxxxxxxxxx
<mailto:troy@xxxxxxxxxxxxxxxxxxxxx> > wrote:
Yes no metals within that propellant, but also, PPG has a fair bit of oxygen
itself, so it’s easier to produce a smoke free exhaust than with something like
a polybutadiene as a binder which might still provide noticeable black carbon
(rich diesel looking) exhaust utilising the same % of AP. I was able to do it
with a 75% ratio of AP.
Troy
From: arocket-bounce@xxxxxxxxxxxxx <mailto:arocket-bounce@xxxxxxxxxxxxx>
[mailto:arocket-bounce@xxxxxxxxxxxxx ;<mailto:arocket-bounce@xxxxxxxxxxxxx> ] On
Behalf Of roxanna Mason
Sent: Wednesday, 8 July 2020 2:43 PM
To: arocket@xxxxxxxxxxxxx <mailto:arocket@xxxxxxxxxxxxx>
Subject: [AR] Re: Making composite APCP in Australia
"no smoke"
Do you mean no aluminum?
On Tue, Jul 7, 2020 at 8:45 PM Ben Brockert <wikkit@xxxxxxxxx
<mailto:wikkit@xxxxxxxxx> > wrote:
On Tue, Jul 7, 2020 at 8:19 PM Troy Prideaux <troy@xxxxxxxxxxxxxxxxxxxxx
<mailto:troy@xxxxxxxxxxxxxxxxxxxxx> > wrote:
BUT, the catch is the processing. You need to invest in the processing kit
or get real clever with the chem.