Study On Close Loop Feedback System Of Variable Flow Ducted Rocket

Ducted rockets with variable fuel flaw control offer potential as low-risk,highperformance propulsion systems for future-generation tactical missiles.With the current improved demand of ducted rocket all over the world,gas flow control technology has become a key research object.The gas flow regulation technology of ducted rocket was investigated in this paper.Firstly,the regulation principle of the gas flow regulation technology of the ducted rocket.The dynamic model of gas regulating system was established based on small perturbation theory,and the transfer function of gas flow and pressure has been obtained.The dynamic model of the pressure of secondary chamber was established based on the theory lumped parameter method,and the transfer function of secondary chamber has been obtained.The transfer function of thrust has been established based on small perturbation theory,and the simulation model was established according to mathematic model of interior ballistic with MATLAB/Simulink.The simulation results are compared with those of the direct type ground test bed.The results are in good agreement with the results of the experiment.Secondly,the relative coordinate system of the ballistic trajectory is defined and the transformation relation between the coordinate systems is established.The equation of mass center of the missile is established.Conclusions can be drawn when the missile is flying in the cruising flight and climbing in the vertical plane: When the missile is in cruising flight,the higher altitude,the smaller thrust demand.The faster speed,the greater thrust demand.When the missile is climbing,the change of the thrust will decrease firstly and then increase gradually,the trend has nothing to do with height difference.The thrust in the high-altitude segment has the same trend to the low-altitude segment.Finally,the design of the gas flow regulation is carried out,the mathematic model of the slide valve and the DC servo motor is established,and the test system is established.ID controller is designed by classical trajectory control system for the entire control simulation.A gas control system is built,which the control of the flight trajectory of the cruising flight and variable height is realized.