now L/D = 12
and I prepare next motors with L/D = 14
I want to know what maximum L/D may be used for maximum Isp
core to diameter ratio (d/D)is about 1/3 in all tests
Very interesting, Serge. Previously you recommended a guideline of length
to grain diameter ration (L/D) = 10 and a core to diameter ratio (d/D)
=1/3
based on your earlier testing. What ratios are you using now?
Richard
On Wed, Jun 19, 2019 at 6:46 AM <spas@xxxxxxxxx> wrote:
More tests of nozzleless motors, previous tests are here
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/
Today's two tests differ by a longer channel, 600 mm instead of 500, and
a
greater mass of propellant KNSB, 1750 g instead of 1500. Lengthening the
core leads to an increase in pressure in the motor and an increase in
the
Isp, so I will increase core length further)
M18 - granulated nitrate
M19 - pure milled nitrate
Thrust curves of the motors with previous results for comparison are
attached.
Video is here
https://www.facebook.com/groups/1396488870646273/permalink/2020337984928022/
Serge Pipko
Kyiv, Ukraine
serge77-rocketry.net
I began a series of tests of nozzleless motors of differentconfigurations
and with different propellants. The purpose of the tests is to findthe
optimal configuration that will give the maximum Isp.diameter
I recently tested 4 nozzleless motors with KNSB propellant. All motors
have the same size and weight, grain outer diameter 50 mm, core
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors differ inused
potassium nitrate.https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/
M14 - granulated KNO3 (contains 0.8% SiO2 anticaking agent)
M15 - granulated KNO3 + 0,5% red iron oxide
M16 - pure milled KNO3
M17 - granulated milled KNO3
The following tests will be with a greater core length, with sodium
nitrate as an oxidizing agent and with the addition of aluminum.
Thrust curves of the motors are attached.
Videos of the tests can be seen here
https://www.facebook.com/serge.pipko.5/posts/450824292327788
