Nice work, Juan !
I notice you used a mixture of Sucrose and sorbitol. Shorter more powerful
burn. Good approach for nozzleless motors. How was this mixture to work
with, with regard to casting. Melt temperature? Pourable?
Richard
On Fri, Jun 21, 2019 at 6:13 PM Juan Parczewski <juanpamas@xxxxxxxxx> wrote:
spas@xxxxxxxxx In the year 2009 I develop a successful nozzleless engine.
Measure done of thrust and camera pressure. I attach the values as
reference..
Regards
On Fri, Jun 21, 2019 at 2:08 AM FreeLists Mailing List Manager <
ecartis@xxxxxxxxxxxxx> wrote:
sugpro Digest Thu, 20 Jun 2019 Volume: 05 Issue: 037
In This Issue:
[sugpro] Re: Nozzleless motors
[sugpro] Re: Nozzleless motors
[sugpro] Re: Nozzleless motors
[sugpro] Re: Nozzleless motors
[sugpro] Re: Nozzleless motors
[sugpro] 38 mm PVC liner for LOKI
[sugpro] Re: 38 mm PVC liner for LOKI
[sugpro] Re: Nozzleless motors
[sugpro] Re: Nozzleless motors
[sugpro] Re: Nozzleless motors
----------------------------------------------------------------------
Date: Thu, 20 Jun 2019 13:14:48 +0300
Subject: [sugpro] Re: Nozzleless motors
From: spas@xxxxxxxxx
Ray, thank you for your kind words)
It is always a pleasure to read of your experiments, Serge.
Do you measure chamber pressure during these tests?
No, but I believe in nozzleless motors pressure may be calculated by
multiplying thrust on exit port area.
From the thrust curves, it does not seem that erosive burning at theexit
is significantly affecting the grain geometry.
There is interesting paper on this matter: "Internal Ballistics
Considerations of Nozzleless Rocket Motors", Journal of Propulsion and
Power, 1999.
http://serge77-rocketry.net/nozzleless0/nozzleless.pdf
The main idea, confirmed by experiment and calculations: the burning speed
of propellant is approximately the same along the entire length of the
core, because the acceleration of combustion due to erosion near the
nozzle is compensated by the acceleration of combustion in the head part
due to a much higher pressure than near the nozzle.
Also, it is interesting
that the M16 test had a shorter duration than the M19 test.
I have used new coffee grinder for M19, so the most plausible reason is
somewhat coarser KNO3. It is unfortunate, because it is impossible now to
correctly compare these two motors.
Have you considered forming an expansion cone in the propellant?
Yes, but not now. Conical insert has long been waiting for its time
(attached).
At first, I want to determine what maximum pressure such an engine can
withstand. So I will try more and more long core. Yesterday I have poured
motor with core length 700 mm, L/D = 14.
On Wednesday, June 19, 2019, 2:32:24 PM GMT, <spas@xxxxxxxxx>wrote:
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/
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/2020337984928022/
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
in
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.motors
I recently tested 4 nozzleless motors with KNSB propellant. All
have the same size and weight, grain outer diameter 50 mm, corediameter
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors differ
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/used
potassium nitrate.
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
------------------------------
Date: Thu, 20 Jun 2019 14:06:54 +0300
Subject: [sugpro] Re: Nozzleless motors
From: spas@xxxxxxxxx
attached picture
Ray, thank you for your kind words)speed
It is always a pleasure to read of your experiments, Serge.
Do you measure chamber pressure during these tests?
No, but I believe in nozzleless motors pressure may be calculated by
multiplying thrust on exit port area.
From the thrust curves, it does not seem that erosive burning at the
exit
is significantly affecting the grain geometry.
There is interesting paper on this matter: "Internal Ballistics
Considerations of Nozzleless Rocket Motors", Journal of Propulsion and
Power, 1999.
http://serge77-rocketry.net/nozzleless0/nozzleless.pdf
The main idea, confirmed by experiment and calculations: the burning
of propellant is approximately the same along the entire length of theto
core, because the acceleration of combustion due to erosion near the
nozzle is compensated by the acceleration of combustion in the head part
due to a much higher pressure than near the nozzle.
Also, it is interesting
that the M16 test had a shorter duration than the M19 test.
I have used new coffee grinder for M19, so the most plausible reason is
somewhat coarser KNO3. It is unfortunate, because it is impossible now
correctly compare these two motors.poured
Have you considered forming an expansion cone in the propellant?
Yes, but not now. Conical insert has long been waiting for its time
(attached).
At first, I want to determine what maximum pressure such an engine can
withstand. So I will try more and more long core. Yesterday I have
motor with core length 700 mm, L/D = 14.wrote:
On Wednesday, June 19, 2019, 2:32:24 PM GMT, <spas@xxxxxxxxx>
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/
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/2020337984928022/
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/1993969987564822/
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.motors
I recently tested 4 nozzleless motors with KNSB propellant. All
have the same size and weight, grain outer diameter 50 mm, corediameter
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors differin
used
potassium nitrate.
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
------------------------------
From: Richard Nakka <richard.rocketry@xxxxxxxxx>
Date: Thu, 20 Jun 2019 13:31:20 -0500
Subject: [sugpro] Re: Nozzleless motors
Nozzleless motor chamber pressure, at any point during the burn, can be
obtained by dividing thrust by the port area.
Regarding the addition of an expansion cone, I have tried that on one of
the nozzleless motors that I flew a while ago (see attached pics). After
test firing a nozzleless motor with a straight core, I decided to add an
expansion cone, and fly the motor in a rocket. Well, the result was
disappointing. The rocket flew a fair amount lower altitude than
predicted.
So it seems that the expansion cone resulted in a loss in thrust. It will
be interesting to see if Serge's upcoming test firing of such a motor is
in
agreement with this finding, or not.
Richard
On Thu, Jun 20, 2019 at 6:07 AM <spas@xxxxxxxxx> wrote:
attached picturepart
Ray, thank you for your kind words)speed
It is always a pleasure to read of your experiments, Serge.
Do you measure chamber pressure during these tests?
No, but I believe in nozzleless motors pressure may be calculated by
multiplying thrust on exit port area.
From the thrust curves, it does not seem that erosive burning at the
exit
is significantly affecting the grain geometry.
There is interesting paper on this matter: "Internal Ballistics
Considerations of Nozzleless Rocket Motors", Journal of Propulsion and
Power, 1999.
http://serge77-rocketry.net/nozzleless0/nozzleless.pdf
The main idea, confirmed by experiment and calculations: the burning
of propellant is approximately the same along the entire length of the
core, because the acceleration of combustion due to erosion near the
nozzle is compensated by the acceleration of combustion in the head
isdue to a much higher pressure than near the nozzle.
Also, it is interesting
that the M16 test had a shorter duration than the M19 test.
I have used new coffee grinder for M19, so the most plausible reason
now tosomewhat coarser KNO3. It is unfortunate, because it is impossible
pouredcorrectly compare these two motors.
Have you considered forming an expansion cone in the propellant?
Yes, but not now. Conical insert has long been waiting for its time
(attached).
At first, I want to determine what maximum pressure such an engine can
withstand. So I will try more and more long core. Yesterday I have
(d/D)motor with core length 700 mm, L/D = 14.wrote:
On Wednesday, June 19, 2019, 2:32:24 PM GMT, <spas@xxxxxxxxx>
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
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/=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
500,
Today's two tests differ by a longer channel, 600 mm instead of
Lengtheningand
a
greater mass of propellant KNSB, 1750 g instead of 1500.
inthe
core leads to an increase in pressure in the motor and an increase
arethe
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
https://www.facebook.com/groups/1396488870646273/permalink/2020337984928022/attached.
Video is here
find
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
differthe
optimal configuration that will give the maximum Isp.motors
I recently tested 4 nozzleless motors with KNSB propellant. All
have the same size and weight, grain outer diameter 50 mm, corediameter
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors
sodiumin
used
potassium nitrate.
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
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/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
------------------------------
Date: Thu, 20 Jun 2019 21:47:49 +0300
Subject: [sugpro] Re: Nozzleless motors
From: spas@xxxxxxxxx
Regarding the addition of an expansion cone, I have tried that on one of
the nozzleless motors that I flew a while ago
Did these motors have equal length of strait core?
(see attached pics). After
test firing a nozzleless motor with a straight core, I decided to add anwill
expansion cone, and fly the motor in a rocket. Well, the result was
disappointing. The rocket flew a fair amount lower altitude than
predicted.
So it seems that the expansion cone resulted in a loss in thrust. It
be interesting to see if Serge's upcoming test firing of such a motor isand
in
agreement with this finding, or not.
Richard
On Thu, Jun 20, 2019 at 6:07 AM <spas@xxxxxxxxx> wrote:
attached picture
Ray, thank you for your kind words)
It is always a pleasure to read of your experiments, Serge.
Do you measure chamber pressure during these tests?
No, but I believe in nozzleless motors pressure may be calculated by
multiplying thrust on exit port area.
From the thrust curves, it does not seem that erosive burning at the
exit
is significantly affecting the grain geometry.
There is interesting paper on this matter: "Internal Ballistics
Considerations of Nozzleless Rocket Motors", Journal of Propulsion
thePower, 1999.speed
http://serge77-rocketry.net/nozzleless0/nozzleless.pdf
The main idea, confirmed by experiment and calculations: the burning
of propellant is approximately the same along the entire length of
nowcore, because the acceleration of combustion due to erosion near thepart
nozzle is compensated by the acceleration of combustion in the head
due to a much higher pressure than near the nozzle.is
Also, it is interesting
that the M16 test had a shorter duration than the M19 test.
I have used new coffee grinder for M19, so the most plausible reason
somewhat coarser KNO3. It is unfortunate, because it is impossible
canto
correctly compare these two motors.
Have you considered forming an expansion cone in the propellant?
Yes, but not now. Conical insert has long been waiting for its time
(attached).
At first, I want to determine what maximum pressure such an engine
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/withstand. So I will try more and more long core. Yesterday I havepoured
motor with core length 700 mm, L/D = 14.wrote:
On Wednesday, June 19, 2019, 2:32:24 PM GMT, <spas@xxxxxxxxx>
(d/D)
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
=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/2020337984928022/500,
Today's two tests differ by a longer channel, 600 mm instead of
Lengtheningand
a
greater mass of propellant KNSB, 1750 g instead of 1500.
inthe
core leads to an increase in pressure in the motor and an increase
arethe
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
attached.
Video is here
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/find
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
differthe
optimal configuration that will give the maximum Isp.motors
I recently tested 4 nozzleless motors with KNSB propellant. All
have the same size and weight, grain outer diameter 50 mm, corediameter
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors
sodiumin
used
potassium nitrate.
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
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
------------------------------
From: Richard Nakka <richard.rocketry@xxxxxxxxx>
Date: Thu, 20 Jun 2019 15:25:26 -0500
Subject: [sugpro] Re: Nozzleless motors
Yes, both motors were identical except the flight motor had an expansion
cone.
On Thu, Jun 20, 2019 at 1:47 PM <spas@xxxxxxxxx> wrote:
of
Regarding the addition of an expansion cone, I have tried that on one
anthe nozzleless motors that I flew a while ago
Did these motors have equal length of strait core?
(see attached pics). After
test firing a nozzleless motor with a straight core, I decided to add
willexpansion cone, and fly the motor in a rocket. Well, the result was
disappointing. The rocket flew a fair amount lower altitude than
predicted.
So it seems that the expansion cone resulted in a loss in thrust. It
isbe interesting to see if Serge's upcoming test firing of such a motor
byin
agreement with this finding, or not.
Richard
On Thu, Jun 20, 2019 at 6:07 AM <spas@xxxxxxxxx> wrote:
attached picture
Ray, thank you for your kind words)
It is always a pleasure to read of your experiments, Serge.
Do you measure chamber pressure during these tests?
No, but I believe in nozzleless motors pressure may be calculated
themultiplying thrust on exit port area.
From the thrust curves, it does not seem that erosive burning at
andexit
is significantly affecting the grain geometry.
There is interesting paper on this matter: "Internal Ballistics
Considerations of Nozzleless Rocket Motors", Journal of Propulsion
burningPower, 1999.
http://serge77-rocketry.net/nozzleless0/nozzleless.pdf
The main idea, confirmed by experiment and calculations: the
thespeed
of propellant is approximately the same along the entire length of
thecore, because the acceleration of combustion due to erosion near
reasonnozzle is compensated by the acceleration of combustion in the headpart
due to a much higher pressure than near the nozzle.
Also, it is interesting
that the M16 test had a shorter duration than the M19 test.
I have used new coffee grinder for M19, so the most plausible
nowis
somewhat coarser KNO3. It is unfortunate, because it is impossible
canto
correctly compare these two motors.
Have you considered forming an expansion cone in the propellant?
Yes, but not now. Conical insert has long been waiting for its time
(attached).
At first, I want to determine what maximum pressure such an engine
ofwithstand. So I will try more and more long core. Yesterday I havepoured
motor with core length 700 mm, L/D = 14.wrote:
On Wednesday, June 19, 2019, 2:32:24 PM GMT, <spas@xxxxxxxxx>
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
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/(d/D)length
to grain diameter ration (L/D) = 10 and a core to diameter ratio
=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
increase500,
Today's two tests differ by a longer channel, 600 mm instead of
Lengtheningand
a
greater mass of propellant KNSB, 1750 g instead of 1500.
the
core leads to an increase in pressure in the motor and an
https://www.facebook.com/groups/1396488870646273/permalink/2020337984928022/in
arethe
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
attached.
Video is here
Allfind
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
the
optimal configuration that will give the maximum Isp.
I recently tested 4 nozzleless motors with KNSB propellant.
coremotors
have the same size and weight, grain outer diameter 50 mm,
aluminum.differdiameter
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors
sodiumin
used
potassium nitrate.
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
nitrate as an oxidizing agent and with the addition of
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/
Thrust curves of the motors are attached.
Videos of the tests can be seen here
https://www.facebook.com/serge.pipko.5/posts/450824292327788
------------------------------
From: Chuck McNeice II <capthaywire@xxxxxxxxx>
Date: Thu, 20 Jun 2019 17:48:51 -0400
Subject: [sugpro] 38 mm PVC liner for LOKI
I would like to use a PVC liner in my 38 mm LOKI 740 motor with sorbitol
bates grains. The LOKI liner slips over the nozzle by about .25 inch. Can
I
just butt the PVC liner to the nozzle or will I need to reduce the ID of
the PVC pipe? If so what is the best way to reduce the ID without a lathe
or other sophisticated tooling? Any other tips would be greatly
appreciated.
------------------------------
Date: Thu, 20 Jun 2019 22:54:51 +0000 (UTC)
From: "Art" <dmarc-noreply@xxxxxxxxxxxxx> (Redacted sender "rocket877"
for
Subject: [sugpro] Re: 38 mm PVC liner for LOKI
If you're using 1 inch, thin wall PVC pipe you should be able the remove
some of the ID with a sharp knife held at an angle and not taking too deep
a cut. Of course the liner needs to have a clean, straight edge to start
with.
Alternatively, an extra O-ring like the one the Loki nozzles use and a
little compression fit might also work.
Mind you I have all the hardware but I've only used it with certifies
Loki reloads..... so far.
Art ApplewhiteNew to sugar
-----Original Message-----
From: Chuck McNeice II <capthaywire@xxxxxxxxx>
To: sugpro <sugpro@xxxxxxxxxxxxx>
Sent: Thu, Jun 20, 2019 4:49 pm
Subject: [sugpro] 38 mm PVC liner for LOKI
I would like to use a PVC liner in my 38 mm LOKI 740 motor with sorbitol
bates grains. The LOKI liner slips over the nozzle by about .25 inch. Can I
just butt the PVC liner to the nozzle or will I need to reduce the ID of
the PVC pipe? If so what is the best way to reduce the ID without a lathe
or other sophisticated tooling? Any other tips would be greatly appreciated.
------------------------------
Date: Thu, 20 Jun 2019 23:34:28 +0000 (UTC)
From: "Ray Rocket" <dmarc-noreply@xxxxxxxxxxxxx> (Redacted sender
Subject: [sugpro] Re: Nozzleless motors
Nozzleless motor chamber pressure, at any point during the burn, can beobtained by dividing thrust by the port area.
Assuming a value for port area after ignition is something of a leap of
faith unless you are measuring chamber pressure.
On Thursday, June 20, 2019, 6:31:41 PM GMT, Richard Nakka <
richard.rocketry@xxxxxxxxx> wrote:
Nozzleless motor chamber pressure, at any point during the burn, can be
obtained by dividing thrust by the port area.
Regarding the addition of an expansion cone, I have tried that on one of
the nozzleless motors that I flew a while ago (see attached pics). After
test firing a nozzleless motor with a straight core, I decided to add an
expansion cone, and fly the motor in a rocket. Well, the result was
disappointing. The rocket flew a fair amount lower altitude than predicted.
So it seems that the expansion cone resulted in a loss in thrust. It will
be interesting to see if Serge's upcoming test firing of such a motor is in
agreement with this finding, or not.
Richard
On Thu, Jun 20, 2019 at 6:07 AM <spas@xxxxxxxxx> wrote:
attached picture
Ray, thank you for your kind words)speed
It is always a pleasure to read of your experiments, Serge.
Do you measure chamber pressure during these tests?
No, but I believe in nozzleless motors pressure may be calculated by
multiplying thrust on exit port area.
From the thrust curves, it does not seem that erosive burning at the
exit
is significantly affecting the grain geometry.
There is interesting paper on this matter: "Internal Ballistics
Considerations of Nozzleless Rocket Motors", Journal of Propulsion and
Power, 1999.
http://serge77-rocketry.net/nozzleless0/nozzleless.pdf
The main idea, confirmed by experiment and calculations: the burning
of propellant is approximately the same along the entire length of theto
core, because the acceleration of combustion due to erosion near the
nozzle is compensated by the acceleration of combustion in the head part
due to a much higher pressure than near the nozzle.
Also, it is interesting
that the M16 test had a shorter duration than the M19 test.
I have used new coffee grinder for M19, so the most plausible reason is
somewhat coarser KNO3. It is unfortunate, because it is impossible now
correctly compare these two motors.poured
Have you considered forming an expansion cone in the propellant?
Yes, but not now. Conical insert has long been waiting for its time
(attached).
At first, I want to determine what maximum pressure such an engine can
withstand. So I will try more and more long core. Yesterday I have
motor with core length 700 mm, L/D = 14.wrote:
On Wednesday, June 19, 2019, 2:32:24 PM GMT, <spas@xxxxxxxxx>
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/
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/2020337984928022/
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/1993969987564822/
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.motors
I recently tested 4 nozzleless motors with KNSB propellant. All
have the same size and weight, grain outer diameter 50 mm, corediameter
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors differin
used
potassium nitrate.
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
------------------------------
Date: Thu, 20 Jun 2019 23:36:12 +0000 (UTC)
From: "Ray Rocket" <dmarc-noreply@xxxxxxxxxxxxx> (Redacted sender
Subject: [sugpro] Re: Nozzleless motors
Was the propellant grain with the expansion cone longer or the same
length as the motor without?
On Thursday, June 20, 2019, 8:25:45 PM GMT, Richard Nakka <
richard.rocketry@xxxxxxxxx> wrote:
Yes, both motors were identical except the flight motor had an expansion
cone.
On Thu, Jun 20, 2019 at 1:47 PM <spas@xxxxxxxxx> wrote:
Regarding the addition of an expansion cone, I have tried that on one of
the nozzleless motors that I flew a while ago
Did these motors have equal length of strait core?
(see attached pics). After
test firing a nozzleless motor with a straight core, I decided to add anwill
expansion cone, and fly the motor in a rocket. Well, the result was
disappointing. The rocket flew a fair amount lower altitude than
predicted.
So it seems that the expansion cone resulted in a loss in thrust. It
be interesting to see if Serge's upcoming test firing of such a motor isand
in
agreement with this finding, or not.
Richard
On Thu, Jun 20, 2019 at 6:07 AM <spas@xxxxxxxxx> wrote:
attached picture
Ray, thank you for your kind words)
It is always a pleasure to read of your experiments, Serge.
Do you measure chamber pressure during these tests?
No, but I believe in nozzleless motors pressure may be calculated by
multiplying thrust on exit port area.
From the thrust curves, it does not seem that erosive burning at the
exit
is significantly affecting the grain geometry.
There is interesting paper on this matter: "Internal Ballistics
Considerations of Nozzleless Rocket Motors", Journal of Propulsion
thePower, 1999.speed
http://serge77-rocketry.net/nozzleless0/nozzleless.pdf
The main idea, confirmed by experiment and calculations: the burning
of propellant is approximately the same along the entire length of
nowcore, because the acceleration of combustion due to erosion near thepart
nozzle is compensated by the acceleration of combustion in the head
due to a much higher pressure than near the nozzle.is
Also, it is interesting
that the M16 test had a shorter duration than the M19 test.
I have used new coffee grinder for M19, so the most plausible reason
somewhat coarser KNO3. It is unfortunate, because it is impossible
canto
correctly compare these two motors.
Have you considered forming an expansion cone in the propellant?
Yes, but not now. Conical insert has long been waiting for its time
(attached).
At first, I want to determine what maximum pressure such an engine
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/withstand. So I will try more and more long core. Yesterday I havepoured
motor with core length 700 mm, L/D = 14.wrote:
On Wednesday, June 19, 2019, 2:32:24 PM GMT, <spas@xxxxxxxxx>
(d/D)
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
=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/2020337984928022/500,
Today's two tests differ by a longer channel, 600 mm instead of
Lengtheningand
a
greater mass of propellant KNSB, 1750 g instead of 1500.
inthe
core leads to an increase in pressure in the motor and an increase
arethe
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
attached.
Video is here
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/find
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
differthe
optimal configuration that will give the maximum Isp.motors
I recently tested 4 nozzleless motors with KNSB propellant. All
have the same size and weight, grain outer diameter 50 mm, corediameter
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors
sodiumin
used
potassium nitrate.
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
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
------------------------------
From: Alex Kuehn <awkpilot@xxxxxxxxx>
Date: Thu, 20 Jun 2019 18:45:10 -0500
Subject: [sugpro] Re: Nozzleless motors
Richard,
Looking at your drawing, unless I'm misunderstanding what you did, I think
the decrease in performance you saw is because the exit cone decreased the
initial Kn of the motor. I believe the same thing happened in the paper
that Serge shared when they did their experiments. I'd be curious if there
would be a significant improvement in performance if you were to simply
lengthen the motor the length of the exit cone when adding the exit cone
(thus having the same Kn and chamber pressure between the motor with the
exit cone and the one without) since I think that would be more telling.
-Alex
On Thu, Jun 20, 2019, 3:25 PM Richard Nakka <richard.rocketry@xxxxxxxxx>
wrote:
Yes, both motors were identical except the flight motor had an expansionone of
cone.
On Thu, Jun 20, 2019 at 1:47 PM <spas@xxxxxxxxx> wrote:
Regarding the addition of an expansion cone, I have tried that on
add anthe nozzleless motors that I flew a while ago
Did these motors have equal length of strait core?
(see attached pics). After
test firing a nozzleless motor with a straight core, I decided to
motor isexpansion cone, and fly the motor in a rocket. Well, the result waswill
disappointing. The rocket flew a fair amount lower altitude than
predicted.
So it seems that the expansion cone resulted in a loss in thrust. It
be interesting to see if Serge's upcoming test firing of such a
byin
agreement with this finding, or not.
Richard
On Thu, Jun 20, 2019 at 6:07 AM <spas@xxxxxxxxx> wrote:
attached picture
Ray, thank you for your kind words)
It is always a pleasure to read of your experiments, Serge.
Do you measure chamber pressure during these tests?
No, but I believe in nozzleless motors pressure may be calculated
themultiplying thrust on exit port area.
From the thrust curves, it does not seem that erosive burning at
burningandexit
is significantly affecting the grain geometry.
There is interesting paper on this matter: "Internal Ballistics
Considerations of Nozzleless Rocket Motors", Journal of Propulsion
Power, 1999.
http://serge77-rocketry.net/nozzleless0/nozzleless.pdf
The main idea, confirmed by experiment and calculations: the
thethespeed
of propellant is approximately the same along the entire length of
core, because the acceleration of combustion due to erosion near
headnozzle is compensated by the acceleration of combustion in the
reasonpart
due to a much higher pressure than near the nozzle.
Also, it is interesting
that the M16 test had a shorter duration than the M19 test.
I have used new coffee grinder for M19, so the most plausible
timenowis
somewhat coarser KNO3. It is unfortunate, because it is impossible
to
correctly compare these two motors.
Have you considered forming an expansion cone in the propellant?
Yes, but not now. Conical insert has long been waiting for its
ofcan(attached).
At first, I want to determine what maximum pressure such an engine
withstand. So I will try more and more long core. Yesterday I havepoured
motor with core length 700 mm, L/D = 14.
On Wednesday, June 19, 2019, 2:32:24 PM GMT, <spas@xxxxxxxxx
wrote:
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
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/(d/D)length
to grain diameter ration (L/D) = 10 and a core to diameter ratio
=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
increase500,
Today's two tests differ by a longer channel, 600 mm instead of
Lengtheningand
a
greater mass of propellant KNSB, 1750 g instead of 1500.
the
core leads to an increase in pressure in the motor and an
comparisonin
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
https://www.facebook.com/groups/1396488870646273/permalink/2020337984928022/are
attached.
Video is here
to
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
Allfind
the
optimal configuration that will give the maximum Isp.
I recently tested 4 nozzleless motors with KNSB propellant.
coremotors
have the same size and weight, grain outer diameter 50 mm,
aluminum.differdiameter
19.3 mm, core length 500 mm, propellant mass 1500 g. Motors
sodiumin
used
potassium nitrate.
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
nitrate as an oxidizing agent and with the addition of
https://www.facebook.com/groups/1396488870646273/permalink/1993969987564822/
Thrust curves of the motors are attached.
Videos of the tests can be seen here
https://www.facebook.com/serge.pipko.5/posts/450824292327788
------------------------------
End of sugpro Digest V5 #37
***************************
