Brief description of CAE technology

1、CAEIntroduction

In recent years, with the rapid development of computer technology, computer-aided engineering technology ((computer-aided engineering, CAE) came into being.CAEanalyzeuseVirtual prototypes replace physical prototypes.Allows analysts to simulate the physical behavior of products based on digital prototypes，Analyze and predict the performance of structures such as strength, stiffness, stability and fatigue life，Development for product，Provide guidance on the design of optimized structure，To solve Provide basis for actual engineering problems. Greatly shorten the design-Analysis cycle accelerates design-Analytical iteration, product innovation capabilitiesImprovementIt has important significance. Especially in the design of aircraft engines,CAEComputational analysis is an integral part.

The design and development of aircraft engines is a very complex process. Every component and every bracket needs to be repeatedly pondered and calculated.CAEComputational analysis becomesStructural Analysisand important tools for structural optimization,andThis improves the reliability of the design, shortens the design cycle and reduces the design cost. Anhui Haery Aviation Power Equipment Co., Ltd.2015Year9It has been passed since its establishmentCAE-design-Trial production-The path of test verification is used to carry out engine research and development and lightweightingdesign.Under this path，CAEGo first andThroughout the entire process of product design and research and development, making product design more reliable and efficient。

picture1IntroducedComparison of product design process before and after CAE

2, Finite Element Analysis

CAEanalyzeMainly refer touseComputers carry out engineering and productsSimulation,analyzeThatPerformance and security trustworthiness，as well asWork and operation status, identify design defects early, and confirm the availability and trustworthiness of engineering, product functionality and performance.CAEThe subject of the analysis method is finite element(FEA，Finite Element Analysis）analyze.

Finite element analysis is a mathematical approximation methodphysicsSimulation of geometry and loading conditions. Finite element analysisDiscrete geometric structures into a finite number of element elements, according to interactions between each element，Assuming an appropriate approximate solution for each unit, then deriving to solve the total satisfactory conditions of this domain (such as the equilibrium conditions of the structure) to obtaincomplexSolution to the problem, a real system that approaches infinite unknown quantity。Finite element calculation not only has relatively high calculation accuracy, but alsoApplicableIn various complex shapes, it has become a very effective means of engineering analysis.

As early as centuries ago, people divided the circle into a finite linear unit to approach the entire circle and find the circumference of the circle. This isrightFinite ElementThoughtEarlier application. In recent years, finite element has been proposed as a method to approximate physical prototypes and solve them using developed computer technology.，widelyApplied to aircraftfieldThe structural strength calculation,Modal analysis, fatigue calculation, etc.

Finite element analysis first discretes the geometric structure into a cell grid, then establishes matrix equations based on the relationship between cells, and then uses the powerful computing function of the computer to solve the equations, thereby simulating the working state, trustworthiness, etc. of the simulated physical structure. The quality of the unit grid directly affects the speed of finite element calculations. picture2It is a more commonly used unit grid at present.

picture2 Finite element mesh

3、CAEAnalysis of general procedures

CAEEngineering AnalysisgenerallymainIncludeThree steps: finite element analysis pre-processing, finite element analysis solution, and finite element analysis post-processing.

Finite element analysis preprocessing: application CADModeling software performs entity modeling of analysis objects, and then establishes a finite element analysis model，This includes reasonable simplification of the analysis object. WillCADModel importCAEIn software (can also be usedCAEModeling functions in software are modeled directly). Then use CAE The software meshs the analysis objects, sets up material and load conditions, boundary conditions, etc., thereby establishing a reasonable finite element analysis model and generating data files required for finite element calculations for use by the solver.

Finite element analysis and solution: (This part of the work is done by the system itself) After the solver receives the data file generated by the pre-processing, the software will analyze the unit characteristics of the finite element model, establish the unit stiffness matrix, and then assemble the overall stiffness matrix, then establish the overall equilibrium equation, and then perform the finite element system solution and generate the analysis results. In general finite element analysis software, computing time is related to computing scale and hardware system. Haery had been very earlyIntroducedLarge serverPerform calculations,MakeCAEcalculateThe speed is relatively fast. Generally large-scale general CAE When software implements finite element analysis, it mostly decomposes into several sub-problems based on the physical, mechanical and digital characteristics of the engineering problem, and is completed by the corresponding analytical subsystems, such as: linear static analysis, dynamic analysis, vibration mode and response analysis, thermal analysis, electromagnetic analysis, fluid analysis, nonlinear analysis and optimization design subsystems.

Finite element analysis post-processing: According to the actual needs of the engineering, the results of finite element analysis are processed and processed, and the analysis results are usually obtained in tables, graphics, images and animations, so that theIntuitiveReasonably analyze and judge the structure. Specifically, it includes the extreme value and position of the physical quantity sought, and analyzes the distribution of related physical quantity on various parts and sections of the object, such as structural deformation.cloudFigures, stress distributioncloudFigures and vibration diagrams, etc.

picture3 General process of CAE analysis

4, conclusion

With the continuous progress of science and technology and the rapid development of social economy, the aviation industry is in development and designCAE The application of technology is becoming more and more frequent.CAE Technology can not only reduce design and R&D costs, shorten development cycles, and avoidCertain trialsIn addition to risks, we can also maximize our own advantages through relevant technical principles to effectively guaranteeeachThe quality and efficiency of component design show the true side of the engine with its own intuitive characteristics. In addition, by CAE The effective application of technology can realize multi-faceted analysis of engine product structure, multi-body dynamics, and safety performance.In addition, from the perspective of practical experience, theoretical analysis andTest and testThe closed-loop structure should be formed as much as possible, and the data collection and comparison between the two should be paid attention to, and the actual results should be used to guide the setting of analysis parameters, and gradually form theHaerycore experience database,Laying a solid foundation for the future development of new engines。