Research On Measurement Planning Based On MBD Statistical Information Of Blisk

The blisk is the core component of the aviation industry.Its production quality is directly related to the service efficiency and life of the aeroengine.According to the development requirements of military(civil)aero-engine for high thrust/weight ratio(large bypass ratio),many integral bladed discs with complex profile and various structures have been widely used.The registration planning,measurement point planning and MBD statistical information integration technology for batch blades are important enabling technologies to realize the integrated closed-loop manufacturing mode of "design-maching-measurement".It has become the key to the development of such integral bladed disc blades in the direction of low cost,high efficiency and high accuracy.This thesis is based on efficient in-situ measurement and high-precision final inspection under the batch production conditions of aircraft engine blisks.In response to the problems of insufficient accuracy in selecting registration points and poor efficiency in planning statistical measurement points caused by early process deformation on the complex surface of blisks,point cloud data processing,six point positioning optimization,statistical importance sampling registration,registration stability/reliability analysis,non-defined section error analysis We have conducted indepth research on key technologies such as MBD integration,and conducted batch validation on multiple models of bladed discs.The main content and research results of the paper are as follows:(1)A six-point optimized pre-positioning and registration algorithm is proposed for the pre-positioning problem of batch blade measurement point data and CAD models of the overall blade disc.The decoupling method is used to determine the layout of key positioning components for each error component,optimize the angle between the primary and secondary directions of the blade,traverse the deformation crosssectional error in the main direction,and achieve the optimal section homogenization in the main direction.Error analysis is conducted on the six optimized positioning points respectively,we have achieved dense measurement point optimization preregistration of batch blades after six-point optimization positioning,and the positioning accuracy is all within 0.02 mm,meeting the accuracy requirements of blade model preregistration.(2)In view of the large and disordered error distribution of measuring points of batch blades,it is necessary to further optimize the registration of blades.After preregistration,a method for selecting the registration control point set of statistical important sampling error is proposed.Based on the stability and reliability of the important sampling sensitivity and statistical error,the error normal distribution statistical sample and the important sampling probability density function are obtained.Verify the rationality of the selection of statistical control points and the objective function.After statistics,the registration deviation is [0.022 mm,0.03mm],and the statistical sampling point deviation is about 0.0214 mm.It meets the requirements of rapid,efficiency and high-precision measurement of aeroengine blades.(3)Aiming at the low efficiency of aeroengine blade measurement and the inability to make full use of batch blade measurement data,a measurement point planning method based on the statistical analysis of undefined section deviation was proposed.Among them,the minimum sample size calculation method required for statistical analysis is given under the given estimation error limit.By analyzing the Spearman rank correlation coefficient of the waviness and torsion of traversing the adjacent undefined sections.The calculation method of the sample size and the planning strategy of the measurement position and quantity of the single blade measurement section are respectively given according to the given estimation accuracy requirements.The accuracy and effectiveness of the recommended manner are verified by the scalar analysis of experimental results.So that guide the subsequent blade measurement point planning based on batch data.(4)In response to the issues of insufficient data management efficiency in the registration measurement process and the inability to efficiently associate batch production data with blade CAD models,MBD technology is introduced into the measurement points and registration planning technology of batch blades,and a measurement information module for overall blade MBD statistics is developed on the NX platform.