That's great that you did this writeup, Steve, I look forward to reading it.
Brings to mind the Metroc and Arcas, two of the few early sounding rockets
that used an end-burner grain.
Richard
On Thu, Dec 21, 2023 at 3:09 PM Steve Peterson <dmarc-noreply@xxxxxxxxxxxxx>
wrote:
As I've mentioned here from time to time, I've been spending a lot of
time exploring end-burners over the past number of years. Each time I've
been tempted to report results of some aspect of that work, I've
realized that I'd need to provide a lot of context before the report
would make any sense, but doing so was well beyond what could be done in
a simple post or two and seemed to require so much work to do properly
that I just kept putting off reporting anything.
At the beginning of September, I finally bit the bullet and over the
past few months have been preparing a sizable writeup that attempts to
go into the matter in some detail, in an organized fashion, and with (I
hope) a certain amount of rigor. The result is attached.
The first part, drawing on numerous simulations, presents the rationale
for low-thrust/long-burn rockets.
The next part contains descriptions of a number of actual rockets (HPR,
amateur, and professional) to illustrate points made in the first section.
The third section talks about grain design; specifically about using
geometry to achieve generally useful thrust profiles without requiring
increases in propellant burn rate.
The final section discusses some practical difficulties of making
low-thrust/long-burn motors and flying rockets with them.
I don't consider myself an expert on any aspect of this subject, so what
is presented here is simply what I've found in my investigations to date
and should be considered subject to revision.
It's about 17 pages; hopefully those of you who choose to wade through
it will find a few things interesting, illuminating, or both.
Comments/questions/etc. welcome....
--Steve
