increase the thrust whit to modification

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jprindustria
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increase the thrust whit to modification

Post by jprindustria » Fri Feb 19, 2010 4:14 pm

perform the amendment and the engine still running, I do not push records before and after this modification cambio.puede volumetric increase engine performance by increasing the pressure in the chamber?
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ace_fedde
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Re: increase the thrust whit to modification

Post by ace_fedde » Fri Feb 19, 2010 6:15 pm

Interesting pressure jet!
Could you please post that again in Spanish? (or french?)
Looks like Google just failed the translation exam :lol:

Fedde
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jprindustria
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Re: increase the thrust whit to modification

Post by jprindustria » Sat Feb 20, 2010 2:33 am

ace_fedde wrote:Interesting pressure jet!
Could you please post that again in Spanish? (or french?)
Looks like Google just failed the translation exam :lol:

Fedde

ok, el motor con la modoficacion funciona correctamente pero no tengo registros de empuje antes y despues del cambio, la pregunta seria: es posible que con esta forma del tubo de escape se pueda aumentar la presion dentro de la camara de combustion como sucede en el lady ana bolein del sr. cottrill? :roll:

ace_fedde
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Re: increase the thrust whit to modification

Post by ace_fedde » Sun Feb 21, 2010 12:17 am

O.k., I think it writes this:

This motor with modification runs correctly but I didn't keep record of performance before and after the modification.
Is it possible that the (modified) shape of the tailpipe causes a higher pressure in the combustion chamber like on Larry Cottrill's Lady Ann Boleyn?
Your scepticism is fuel for my brain.

metiz
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Re: increase the thrust whit to modification

Post by metiz » Sun Feb 21, 2010 12:52 am

perform the amendment and the engine still running, I do not push records before and after this modification cambio.puede volumetric increase engine performance by increasing the pressure in the chamber?

To Spanish
¿Realiza la enmienda y el motor todavía corriendo, yo no empujo registros antes de y después de este cambio.puede de modificación desempeño volumétrico de motor de aumento aumentando la presión en la cámara?

To English
It carries out the amendment and the motor still running, I do not push registrations before and after this change.puede of modification volumetric performance of motor of increase enlarging the pressure in the camera?

To Spanish
¿Lleva a cabo la enmienda y el motor todavía corriendo, yo no empujo matrículas antes de y después de este cambio.puede de modificación desempeño volumétrico de motor de aumento que amplía la presión en la cámara?

To English
He carries out the amendment and the motor still running, I do not push registrations before and after this change.puede of modification volumetric performance of motor of increase that expands the pressure in the camera?

To Spanish
¿El lleva a cabo la enmienda y el motor todavía corriendo, yo no empujo matrículas antes que y después este cambio.puede de modificación desempeño volumétrico de motor de aumento que expanda la presión en la cámara?

To English
The he carries out the amendment and the motor still running, I do not push registrations before that and later this change.puede of modification volumetric performance of motor of increase that expand the pressure in the camera?

To Spanish
¿El él lleva a cabo la enmienda y el motor todavía corriendo, yo no empujo matrículas antes que que y posterior este cambio.puede de modificación desempeño volumétrico de motor de aumento que expanda la presión en la cámara?

To English
The he carries out the amendment and the motor still running, I do not push registrations before that that and subsequent this change.puede of modification volumetric performance of motor of increase that expand the pressure in the camera?

To Spanish
¿El él lleva a cabo la enmienda y el motor todavía corriendo, yo no empujo matrículas antes que que que y subsiguiente este cambio.puede de modificación desempeño volumétrico de motor de aumento que expanda la presión en la cámara?

To English - Equilibrium achieved! :mrgreen:
The he carries out the amendment and the motor still running, I do not push registrations before that that and subsequent this change.puede of modification volumetric performance of motor of increase that expand the pressure in the camera?
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ace_fedde
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Re: increase the thrust whit to modification

Post by ace_fedde » Sun Feb 21, 2010 10:10 am

Good old Google failed the exam again but made lot's of fun :lol:

But Jpr still doesn't have an answer on his question:
ace_fedde wrote:O.k., I think it writes this:

This motor with modification runs correctly but I didn't keep record of performance before and after the modification.
Is it possible that the (modified) shape of the tailpipe causes a higher pressure in the combustion chamber like on Larry Cottrill's Lady Ann Boleyn?
Your scepticism is fuel for my brain.

metiz
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Re: increase the thrust whit to modification

Post by metiz » Sun Feb 21, 2010 11:17 am

The divergant/ reflector does that in a pulse-jet I think but I'm not to sure about pressurejets. Logic dictates that it might but I'm no expert on pressurejets.
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jprindustria
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Re: increase the thrust whit to modification

Post by jprindustria » Sun Feb 21, 2010 4:30 pm

metiz wrote:The divergant/ reflector does that in a pulse-jet I think but I'm not to sure about pressurejets. Logic dictates that it might but I'm no expert on pressurejets.
the vibrational behavior of jet presure is the same with the pulsejet or different? if they are equal then the change can work :D

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Re: increase the thrust whit to modification

Post by Viv » Sun Feb 21, 2010 5:20 pm

jprindustria wrote:
metiz wrote:The divergant/ reflector does that in a pulse-jet I think but I'm not to sure about pressurejets. Logic dictates that it might but I'm no expert on pressurejets.
the vibrational behavior of jet presure is the same with the pulsejet or different? if they are equal then the change can work :D
Hi jpindustria

Yes the pressure jet is identical to a valveless pulse jet in operation, the same acoustic pressure waves are used in both types of engine, the pressure jet is basically a "Logan" type side ported valveless pulse jet with an "ejector" type induction system and a set of velocity stacks to tune the intake stack.

Viv
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jprindustria
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Re: increase the thrust whit to modification

Post by jprindustria » Mon Feb 22, 2010 1:57 am

Viv wrote:
jprindustria wrote:
metiz wrote:The divergant/ reflector does that in a pulse-jet I think but I'm not to sure about pressurejets. Logic dictates that it might but I'm no expert on pressurejets.
the vibrational behavior of jet presure is the same with the pulsejet or different? if they are equal then the change can work :D
Hi jpindustria

Yes the pressure jet is identical to a valveless pulse jet in operation, the same acoustic pressure waves are used in both types of engine, the pressure jet is basically a "Logan" type side ported valveless pulse jet with an "ejector" type induction system and a set of velocity stacks to tune the intake stack.

Viv
Viv you experienced with these geometry exhaust pipe in jet pressure?, from what I've read a lot of these engines known.

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Re: increase the thrust whit to modification

Post by Viv » Mon Feb 22, 2010 11:54 am

Hi jpindustria

I have only tried this type modification as a computer model not as a real engine on a test stand, the model did not perform as I wanted at that time.

Viv
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Hughe
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Re: increase the thrust whit to modification

Post by Hughe » Wed Jan 26, 2011 7:13 am

viv,
could you describe or post some pic of that where you face the prblem i mean the stage at which the result is poor

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Re: increase the thrust whit to modification

Post by Viv » Wed Jan 26, 2011 3:34 pm

Hughe wrote:viv,
could you describe or post some pic of that where you face the prblem i mean the stage at which the result is poor
Hi Hughe

The problem with this type of modification placed directly behind the chamber convergent section (to the tailpipe) is that it affects the wave timing around the bottom of the third stage intake.

If you get it right you can make an improvement in the engines breathing but it will be at the expense of your operating range as the engine will be very highly tuned to work at a narrow set of conditions (temperature/frequency) starting will be harder and throttle range decreased.

If peek power at a certain setting is all you want then it is ok but a real world engine may be very difficult to use if you apply too much tuning to this area of the engines geometry, by too much tuning I mean making the operating band were the wave timing is correct for good breathing very narrow.

Hope that helps

Viv
"Sometimes the lies you tell are less frightening than the loneliness you might feel if you stopped telling them" Brock Clarke

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