It was a 2.5K COTS item and the aluminum version was going to be 10K NRE.
Unless your building a hovering vehicle with long burn times all at ground
level, I just can't make the mass case for a pump work until you are at
Falcon 1 sizes. Ventions seems to think its a good idea for a small
vehicle, but they are doing LOX and using really thin e-beam welded tanks.
Looking here:
http://hydrogen-peroxide.us/history-US-General-Kinetics/AIAA-2001-3838_History_of_RMI_Super_Performance_90_Percent_H2O2-Kerosene_LR-40_RE-pitch.pdf
thrust to weight to a 10K lb pumped motor...~50 I get 100:1 in my low
pressure biprop HTP motors... at 300 psi inlet.
I think I'll get very similar vacuum ISP. (Have not flown at vacuum, but
adjusting my ground level ISP to Vac seems like I'll do slightly better
than their numbers.)
On Wed, Apr 6, 2016 at 2:03 AM, Liam McQuellin <lmcquellin@xxxxxxxxxxx>
wrote:
Thanks Paul,
The application I am looking at is to support a higher chamber pressure in
a peroxide VTVL rocket; without the need for aluminum lined filament wound
tanks etc. Regarding the quote they gave you for a aluminum billet version,
was the cost reasonable (I understand that is a big vague). If you were to
compare it to the total vehicle cost for Blue Ball as a reference. Did you
ever collect any performance data of the pump during testing? Or it didn't
get that far because of the seal issues?
All the best,
Liam
Liam McQuellin
Director
Australian Space Research Institute
On Tue, Mar 29, 2016 at 11:53 AM, Paul Breed <paul@xxxxxxxxxx> wrote:
That pump was solid stainless steel and very heavy, I got the company
that built it to quote me one in billet aluminum and was going to test the
stainless COTS one first. I abandoned the project when testing the unit
revealed some custom buna-n seals that theY promised me were viton.
I think an aluminum or poly gear pump would be the way to go if I were
doing it today. Given that for launchers under 50lbs payload a pump makes
no sense as the minimum wall thickness of realizable tanks, and thin wall
3d printed al motors makes the system level benift for small pumps
negligible or maybe actually negative.
On Mon, Mar 28, 2016 at 5:40 PM, Liam McQuellin <lmcquellin@xxxxxxxxxxx>
wrote:
Hi All,
I was actually talking to another arocket member about this last night.
I recall Paul Breed manufacturing a custom peroxide pump back in 2008.
http://unreasonablerocket.blogspot.com/2008/12/merry-christmas.html?m=0
And
http://unreasonablerocket.blogspot.com/2008/12/why-i-like-this-project.html?m=0
The pump appears to be an off the shelf product with a bldc motor and
Pauls custom housing and gear train. Paul do you have any additional
information on this pump? Was it's performance ever measured? I am
interested in its compatibility with peroxide, especially if the pump is
avaliable commercially.
Regards,
Liam
On Tuesday, 29 March 2016, Carl Tedesco <ctedesco@xxxxxxxxxxxxxx> wrote:
Bruno,
I do not have a COTS solution for you, but I have wondered if a pump
like this
<http://www.lrsperformanceinc.com/parts-and-services/magna-fuel/>
could be made to work. My biggest worry would be the metal-on-metal gear
friction, so I always wondered if the gears could be replaced with machined
plastic gears
---Carl
-----Original Message-----
From: arocket-bounce@xxxxxxxxxxxxx [mailto:arocket-bounce@xxxxxxxxxxxxx]
On Behalf Of Bruno Berger
Sent: Monday, March 28, 2016 4:41 AM
To: arocket@xxxxxxxxxxxxx
Subject: [AR] Recommendations for a lightweight HTP pump
I am looking for a lightweight high-pressure pump which can be driven
by a brushless motor (if possible directly or via gearbox). It has to pump
HTP, so it should be compatible or at least modifiable.
Delta pressure range: 15-25 bar (220-360 psi) Inlet pressure: 0.5-2 bar
(7-29 psi)
Volume* : 0.3 l/s (0.08 gal/s)
Thanks for any hints!
Bruno
"At that time [1909] the chief engineer was almost always the chief
test pilot as well. That had the fortunate result of eliminating poor
engineering early in aviation" (Igor Sikorsky)
--
Bruno Berger
Swiss Propulsion Laboratory
E-Mail: bruno.berger@xxxxxx (HTML-Mails will be dropped!)
PGP: http://www.spl.ch/contact/Bruno.Berger.asc
WWW: http://www.spl.ch
HAM: HB9RSU
--
Liam McQuellin
Director
Australian Space Research Institute
