Shane:
Is this done after or during mixing?
If the latter, I—and I suspect others—would be very interested in your
process: for example, how long do you apply vacuum / vibration before
casting the grain(s)? Have you documented the difference in final
propellant density?
I found that 10 minutes under vacuum after mixing resulted in density going
from 0.055 to 0.058 lbsm. / cu. in., for a specific propellant formulation,
for example. Do you have a guess as to what additional density might be
achieved from vibration? Note that theoretical is 0.065 for this
propellant.
I’m trying to make an economic calculation here: for my next generation
(composite) 6” motors, getting to 0.060 lbsm. / cu. in. Increases
propellant fraction from 70% to 72%; given my estimate of the cost of a
vibratory table, I’m looking to understand if that investment produces
greater performance gain than alternative weight saving investments.
Bill
On Wed, Jan 29, 2020 at 10:34 AM <spcdestiny01@xxxxxxxxx> wrote:
At my school we use the vacuum while it’s on the vibration table to remove
all air bubbles and increase the density.
Hope that helps,
Shane Cullen
Sent from my iPhone
On Jan 29, 2020, at 10:27 AM, William Claybaugh <wclaybaugh2@xxxxxxxxx>wrote:
propellant, with or without vacuum?
Anyone have experience w/ vibratory compaction if solid rocket
Initial search did not turn up anything specific....
Bill
