Now that you mention it Anthony, I remember my colleague Al who was the
senior test engineer for Amroc,where we met at Edwards AFB AFRL,
they use a cavitating venturi on their 250KLbF LOx/HTPB hybrid. It doubled
as the main LOx propellant valve as well.
K
On Sun, Jul 26, 2020 at 4:36 PM Anthony Cesaroni <anthony@xxxxxxxxxxx>
wrote:
Before advancing to aft-injected hybrid motors, we used annular cavitating
venturis on head-end injection systems. They worked well in terms of
stability, especially as motors got larger.
Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
http://www.cesaronitech.com/
(941) 360-3100 x1004 Sarasota
(905) 887-2370 x222 Toronto
-----Original Message-----
From: arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> On
Behalf Of Henry Spencer
Sent: Sunday, July 26, 2020 5:41 PM
To: Arocket List <arocket@xxxxxxxxxxxxx>
Subject: [AR] Re: My Cavitating Venturi
On Sun, 26 Jul 2020, 1bcjolly wrote:
Ken,
Not being a liquid man there is a lot that I don't know. Are these
cavitating ventures used as metering orifices for the purpose of o/f
mixture control or do they serve some other purpose?
As Ken said, they're for maintaining constant flow despite changes in
downstream conditions (within limits). Controlling mixture ratio is one
application -- the Apollo LM descent engine had (variable) cavitating
venturis as part of its throttling system. They can help suppress
low-frequency oscillations by breaking feedback loops, since a surge in
back pressure doesn't reduce the flow rate through a C.V. They can hold a
catalyst's flow rate constant even as chamber pressure builds up. They can
stabilize performance in an engine with an ablative throat (or a throat
with a soot layer that occasionally flakes off) whose exact throat-area
history isn't fully predictable. Etc. They do this without nearly as much
pressure loss as a plain orifice.
Henry