You are NOT understanding the importance of the shape of the duct at each end of this valveless pulsejet.offom wrote:Today we cut out the flange out of exhaust tailcone. It got its steady state (with compressor sadly) quickly than before but as we stop compressor air, it stops. We will try to replace injector as you said and add 100 mm length to straight 34 mm diameter exhaust section. Try try try
At the front ("intake") end, the intake flare must be quite precise and within established limits. This promotes intake flow with minimum resistance and outflow with max. Please refer to prior art and create a simple flared cone--or better yet a bellmouth which will maximize this effect.
At the "exhaust" end you need to remove the ending flare which interferes with the important return reflection of the exhaust pulse to create more important and powerful timing events within the core of the motor.
Your efforts are mechanically laudable but are interfering with important events within the design of this engine. You need to start thinking like a pulsejet engineer now!!