Research On Measuring And Adjusting Method Of Rotor Quality Characteristics Of Aero Engine Core Based On Stack Assembly

As the heart of the aircraft,the aero engine concentrates the most advanced material technology,processing technology,measurement technology and control technology,which is an important manifestation of a country's industrial,technological and national defense strength.Among them,the core aircraft is composed of multi-stage rotors and is the core component of an aero engine.Its quality characteristics will directly affect the start and stop characteristics of the aero engine and the smoothness of operation,and even affect the overall attitude control and acceleration and deceleration fighting performance of the fighter.In order to improve the quality characteristics of the aero-engine multi-stage rotor after assembly,the quality characteristics of the single-stage rotor must be accurately measured,and the transformation mechanism of the quality characteristics from the single-stage rotor to the assembly during the assembly process must be thoroughly studied.Aiming at the problem that the current aero-engine rotor is difficult to accurately measure all quality characteristics through one clamping,and there is a lack of a stack optimization method for quality characteristics.An aero-engine rotor quality characteristic measurement model is established,aero-engine rotor quality characteristic integrated measurement equipment is designed,and aero-engine rotor quality characteristic stacking assembly method is proposed in this paper.In addition,this paper evaluates the uncertainty of the measurement model based on the Monte Carlo method.The simulation analysis of the mass characteristic probability density curve verifies the effectiveness of the proposed stack optimization method.In this way,the quality characteristics of the multi-stage rotor after assembly are optimized,and the assembly pass rate is improved.In order to accurately measure the quality characteristics of the single-stage rotor from the perspective of the theoretical model,this paper e stablishes a measurement model of the aero-engine rotor quality characteristics.Among them,the centroid measurement model was established based on the multi-point weighing method,and the influence of the installation and processing errors of the measure d object on the centroid measurement was analyzed.On this basis,the coordinate transformation model of the centroid measurement was established,and the measured object's own coordinates were obtained.The center of mass coordinates under the system.Based on the torsion pendulum method,the rotational inertia measurement model is established,and the damping ratio in the measurement process is solved by the free attenuation method.The inertial product measurement model is established based on the inertial ellipsoid method,and the best measurement posture is solved by error analysis calculation,which improves the measurement accuracy.In order to accurately measure the quality characteristics of a single-stage rotor from the perspective of hardware structure,an integrated measurement device for the aero-engine rotor quality characteristics was designed.The mass characteristic measuring equipment mainly includes two main parts of a centroid measuring module and a rotational inertia measuring module.Among them,the three-point weighing structure of the weighing module was designed based on the principle of the support point layout and the spherical-V block support theory,which achieved the complete positioning of the weighing platform in the horizontal plane,and calculated each part of the weighing process according to the error formula Accuracy distribution of item parameters.Based on the theory of fluid mechanics,the finite element simulation of the air bearing system of the rotational inertia measurement module is carried out.The results show that the air bearing has large bearing capacity,uniform pressure distribution,large gas film rigidity,and high rotary reference accuracy.In addition,the rotor mass characteristic measurement process is planned,and the accurate measurement of the rotor mass,centroid position,rotational inertia and inertial product is achieved through two parts: no-load measurement and load measurement.In order to minimize the quality characteristic error of the multi-stage rotor assembly of the core machine,a stacking optimized assembly model of the aeroengine rotor quality characteristic was established.Among them,based on the transmission mechanism and law of processing errors in the assembly,a coordinate conversion method from single-stage rotor to assembly is proposed,and the stacking optimization assembly theoretical models of centroid and rotational inertia are established respectivelyIn this paper,the evaluation of the uncertainty of the measurement of the quality characteristics of the rotor of the aero engine core and the verification of the stack model are completed.Among them,the measurement uncertainty of the position of the center of mass of the rotor of the core machine and the rotational inertia was evaluated based on the Monte Carlo method.The results show that the measurement uncertainty of the centroid coordinate can reach 1mm,and the measurement uncertainty of the rotational inertia can reach 1%.Based on the Monte Carlo method,the probability density curve of the multi-stage rotor assembly is solved.The results show that compared with the direct assembly and the worst assembly.The average gravity moment of the two-stage rotor decreased by 42.5% and 64.6% and the average moment of inertia of the two-stage rotor decreased by 52.4% and 71.4%.The average gravity moment of the three-stage rotor decreased by 56.3% and 66.7% and the average rotational inertia of the three-stage rotor is reduced by 81.3% and 87.5%.This verifies the effectiveness of the proposed quality characteristics stack assembly method.