Some overall thoughts:
You should select propellant tanks that are way stronger than you need
for static testing. Once you get things running well on a test stand,
then you can start thinking about flight weight tanks. For typical
pressures used in amateur rocketry, aluminum DOT rated cylinders are
good choices as they are typically rated for 2000-3000 psi (unmodified)
and the heel is thick enough to drill and tap for an NPT fitting.
You also may want to consider making an uncooled engine first to shake
out the problems with your test stand. I certainly learned a lot and on
my first few hot tests that made it easier when I got around to testing
my first regen engine.
To take measurements on the test stand, you can go cheap and reliable
(video camera looking at pressure gauges) or you can go with a full data
acquisition system which is a lot more complex and expensive but much
more flexible.
For an engine in the size range you're talking about, you're going to
want some sort of igniter as direct spark ignition probably won't work.
For controlling propellant mass flow rate, typically you characterize
the injector flow rate vs. pressure using water to get a discharge
coefficient curve. Then assuming a nominal chamber pressure, you can
set your tank pressure regulator appropriately.
I agree with the others, the two books you want are Rocket Propulsion
Elements by Sutton, and either NASA SP-125 or Modern Engineering for
Design of Liquid Propellant Rocket Engines from the AIAA.
There is lots of helpful information in the aRocket archives, both on
freelists.org and on the older list archive located at
www.blastzone.org/arocket. Based on your questions, I would start with
the two books mentioned, then start going through the aRocket archives
to get practical tips.
-Bob
On 05/19/2016 04:54 PM, Wensberg, Dana A. (2018) wrote:
New to the forum. Forgive me if this is not how things work.
My general questions are:
How can one make or obtain a tank for propellant when you want to use inert gas
to pressurize it. Should I purchase a bladder and try to jam it into an old
chemistry cylinder? Or should I have the thing professionally made (for like
$2500 a piece). The rocket size is about 5 inches in diameter with a design
thrust of around 2000 lb. Kerosene and LOX
How should I meter the flow? Should I use an orifice or venturi? How can I
insert the pressure gauges and thermocouples everywhere? How do the pressure
gauges work?
Any help would be greatly appreciated?.
Regards,
Dana