Study On Pressure Oscillation Mechanism And Suppression Measure Of Regenerative Liquid Propellant Gun

This paper studies pressure oscillation mechanism and suppression measures of RLPGby the four aspects of longitudinal vibration of regenerative injection structure, radialdeformation of injection hole, oscillation fluid of combustion chamber gas and fuelreservoir nonlinear wave. The main research content and production are concluded asfollowings:Based on the four-end network theory, the longitudinal vibration frequency equationof the floating pole is established, and the longitudinal vibration finite element model ofregenerative injection piston is established by applying large'finite element software. Thepressure oscillation mechanism and suppression measure have been researched combiningthe frequency spectrum analysis result of experiment pressure. The results indicate that thelongitudinal vibration of regenerative injection structure is an important influence factor ofpressure oscillation for RLPG, and keeping invariance of the total mass of regenerativeinjection structure and the structure length of floating pole and piston, the pressureoscillation could be suppressed by changing structure dimension of floating pole, butchanging the wall thickness of piston cylinder is difficult to suppress the pressureoscillation of RLPG.The model of interiors ballistic for RLPG is established, in which the radialdeformation of injection pole has not been considered and the combustion of solid primerand ignition delay phenomena has been considered. Based on the contact nonlinearfinite-element theory, the contact nonlinear finite-element model of injection hole radialdeformation is established. The interiors ballistic model is established in which the radialdeformation of injection hole has been considered by designing interface program. Theradial deformation of injection hole that influences to pressure oscillation has been studied.The results show that the radial deformation of injection hole is not an important influencefactor of pressure oscillation for RLPG.The pressure oscillation component of combustion chamber for RLPG has beenextracted by the technique of wavelet analysis, and the combustion chamber shape inwhich the pressure oscillation is relative concentration has been defined. The equation ofoscillation fluid characteristic frequency has been established. The pressure oscillationmechanism and suppression measures in combustion chamber for RLPG had been researched. The results show that the oscillation fluid's characteristic frequency that isaroused, is an important influence factor of pressure oscillation in combustion chamber,but keeping variance of gas temperature and combustion chamber volume, the pressureoscillation in combustion chamber for RLPG is difficult to be suppressed by changing theradio of radius and length of combustion chamber.The forecasting mathematical model of shock waves had been established, and thenthe pressure oscillation mechanism and suppression measures in fuel reservoir for RLPGhad been researched. The results indicate the shock waves is a main factor to produce thepressure oscillation in fuel reservoir, using the OTTO-â…¡LP is better than 1846 LP tosuppress the shock waves on the same conditions, and by controlling the movement ofregenerative injection structure, the shock waves could be suppressed and the pressureoscillation in fuel reservoir for RLPG is suppressed on the conditions of certain type of LPand charge mass.