Last time I looked at one of those RAM units, I thought it ran to six
figures... Have they come down in price?
Best -- Terry
On 1/30/2020 2:58 PM, William Claybaugh wrote:
Anthony:--
Resonate Acoustic Mixing (RAM) appears to offer the ability to mix very heavily loaded pastes with low shear (in contrast to conventional mixing) and very quickly (seconds rather than minutes or hours). Since there is no mixing paddle, there is no vacuum rotary joint and applying vacuum is trivial.
I’ll apply vibration to the post mixing vacuum for my next test just to see what improvement that produces but will be looking into using vibration to get rid of the conventional mixer altogether.
Bill
On Thu, Jan 30, 2020 at 9:31 AM Anthony Cesaroni <anthony@xxxxxxxxxxx <mailto:anthony@xxxxxxxxxxx>> wrote:
If you mix under a vacuum, vibration should not be required.
One approach I saw being used by an amateur group in the 90s was
to mix the propellant into a simple cylindrical vacuum chamber
that had a shaft connected to a set of blades inside. The shaft
had a rotary seal that permitted the shaft to move in and out the
length of the tube as well as rotate. The tube was made from clear
polymer and was about 6” in diameter and 48” long. I have no idea
how well this worked in practice and what was used to mitigate
shaft deflection and possible blade strike. This was the 90s when
HPR was the “wild west” of rocketry. They published a brochure
about it that I may still have in my Toronto library.
Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
http://www.cesaronitech.com/
(941) 360-3100 x101 Sarasota
(905) 887-2370 x222 Toronto
*From:* arocket-bounce@xxxxxxxxxxxxx
<mailto:arocket-bounce@xxxxxxxxxxxxx>
<arocket-bounce@xxxxxxxxxxxxx
<mailto:arocket-bounce@xxxxxxxxxxxxx>> *On Behalf Of *William
Claybaugh
*Sent:* Thursday, January 30, 2020 11:08 AM
*To:* arocket@xxxxxxxxxxxxx <mailto:arocket@xxxxxxxxxxxxx>
*Subject:* [AR] Re: Vibratory compaction
Anthony:
Yep. But also about understanding the cost of performance.
I’m also wondering about just doing all the mixing with vibration
and vacuum. It seems possible that for 150 lbm. lots that might
be a plausible solution.
Bilk
On Wed, Jan 29, 2020 at 8:19 PM Anthony Cesaroni
<anthony@xxxxxxxxxxx <mailto:anthony@xxxxxxxxxxx>> wrote:
Bill,
Is this about your pursuit of improving propellant density
without hving access to vacuum mixing equipment?
Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
http://www.cesaronitech.com/
(941) 360-3100 x101 Sarasota
(905) 887-2370 x222 Toronto
*From:* arocket-bounce@xxxxxxxxxxxxx
<mailto:arocket-bounce@xxxxxxxxxxxxx>
<arocket-bounce@xxxxxxxxxxxxx
<mailto:arocket-bounce@xxxxxxxxxxxxx>> *On Behalf Of *William
Claybaugh
*Sent:* Wednesday, January 29, 2020 12:51 PM
*To:* arocket@xxxxxxxxxxxxx <mailto:arocket@xxxxxxxxxxxxx>
*Subject:* [AR] Re: Vibratory compaction
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
<mailto: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 <mailto:wclaybaugh2@xxxxxxxxx>> wrote:
>
>
> Anyone have experience w/ vibratory compaction if solid
rocket propellant, with or without vacuum?
>
> Initial search did not turn up anything specific....
>
> Bill
