Research On Dynamic Characteristics Of Viscoseal-rotor System Of Rocket Liquid Oxygen Turbine Pump

Turbine pump is one of the key components of liquid rocket engine,its reliability directly affects the safety of liquid rocket engine.The sealing device of the turbo pump is the segment extremely easy to cause accident,which is especially worthy of attention.Therefore,the viscoseal of turbo pump is taken as the research object,therefore,the viscoseal of turbo pump is taken as the research object,and the flow field characteristics,leakage characteristics and dynamic characteristics of the seal are studied separately.Based on the verification of grid independence and the verification of turbulence model,the influence of viscoseal structure parameters including spiral groove depth,relative groove width,spiral angle,sealing gap on the flow field characteristics such as pressure distribution and velocity distribution of tu rbo pump viscoseal is studied,the influence of the viscoseal structure parameters on the leakage characteristics of the viscoseal is obtained.Based on the CFD dynamic grid technique,identification of dynamic coefficient of viscoseal of turbine pump by calculating mechanical impedance,and the results are compared with the test results to verify the correctness of the method.Based on this,the dynamic coefficients including the main stiffness,main damping,cross-stiffness and cross-damping of the viscoseal of the turbo pump are identified under different sealing clearance,rotational speed,eccentricity and differential pressure conditions,The influence of different conditions on the dynamic coefficient of the viscoseal is summarized.Based on the simplification of the centrifugal wheel,the induction wheel and the turbine,the ABAQUS is used to optimize the material properties according to the simplified model,and the finite element modeling of the liquid-gas turbine pump viscoseal-rotor system is carried out to solve the criticality Speed and vibration mode of the viscoseal-rotor system.The unbalance amount is applied to the shaft end nut,seal,pump bearing and turbine bearing of the finite element model,and the Newmark iterative method is used to solve the vibration characteristics of the viscoseal-rotor system under unbalanced excitation.The degree of the change in vibration response of the viscoseal-rotor system is analyzed,including considering the fluid excitation and without considering the fluid excitation.