Well, I had a crazy idea, but it's not going to work. I thought, what if
the nitrous/acetylene mixture were already going faster than the detonation
velocity before you light it? Then the detonation would move relative to
the motion of the gas, and it wouldn't be able to propagate upstream in the
ground reference frame.
How would this work? You would start with a cold gas rocket and somehow
trip the detonation at a point in the supersonic expansion bell once the
gas is going fast enough. The detonation would boost the temperature and
static pressure and then you would have a second stage expansion bell.
The problem is there's no way you are going to get a cold gas rocket to a
sufficiently high exhaust velocity. Also, would the detonation propagate
up the boundary layer that isn't supersonic? And you'd have to worry about
what happens in the startup and shutdown transients. And it would be an
inferior thermodynamic cycle, would that erase the performance advantage?
On Thu, Jan 30, 2020 at 7:13 PM Anthony Cesaroni <anthony@xxxxxxxxxxx>
wrote:
I ran it in LLNL Cheetah code a few years ago. It was around 6000 ft/sec
IIRC correctly. The rest of the details don’t come to mind.
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 <arocket-bounce@xxxxxxxxxxxxx> *On
Behalf Of *Robert Steinke
*Sent:* Thursday, January 30, 2020 10:04 PM
*To:* arocket@xxxxxxxxxxxxx
*Subject:* [AR] Detonation velocity in nitrous/acetylene monopropellant
If there's anyone on the list who knows, and can tell me, what is the
detonation propagation velocity in the recently discussed nitrous/acetylene
monopropellant? And is it a constant mach number if the temperature of the
propellant changes, or a constant velocity, or something more complicated?
Thanks,
Bob
