Research On Multi-physics Simulation Algorithm And CAE Technology For Complex Electronic Products

Since the 1990 s,the electronics industry has embarked on a path of rapid development,with continuous innovation and technological progress driving electronic products towards miniaturization,integration,and enhanced functionality.Electronic products typically consist of various electronic devices and external components.Among these,electronic devices provide the fundamental technology and functionality required by electronic products,and their performance parameters are the most critical aspects to consider in design.Due to the complex operating environments of electronic products,involving multiple physical fields such as electromagnetic,thermal,and mechanical,traditional segregated physical field simulations may overlook some important interactions,leading to limitations in design.Among the relevant research methods,the shortcomings of traditional theoretical analysis methods are that they are only applicable to simple structures.Given the reality of electronic devices having more complex structures,this method has been outdated.Although experimental testing methods are feasible,their drawbacks include high cost,long cycles,and unavoidable influences of testing environments on experimental results,thus possibly leading to significant errors.Compared to the previous two research methods,simulation analysis not only has efficiency but also low cost.Therefore,researching the multi-physics field simulation and Computer-Aided Engineering(CAE)technology of electronic products is of significant importance.This dissertation focuses on a series of research on the multi-physics field simulation and CAE technology of electronic products,conducting in-depth analyses of electromagnetic analysis,thermal analysis,force analysis,and multi-physics field coupling issues of electronic devices,and further developing comprehensive multiphysics field simulation CAE software.The main works and innovations of this dissertation are as follows:Research on electromagnetic modeling and simulation based on the finite element method(FEM).Firstly,regarding the three-dimensional electromagnetic field boundary value problem,combined with electromagnetic basic theory,finite element formulas are analyzed and derived,and in-depth research is conducted on boundary conditions and excitation application issues.After spatial discretization using high-order stacked vector basis functions,considering the practical need for large-scale finite element linear sparse matrices,a mixed PMG-MFBICF preconditioning technology is proposed based on the generalized conjugate residual iteration method to improve computational efficiency.Finally,starting from Ohm’s law,an electromagnetic modeling algorithm based on the finite element method is proposed,achieving equivalent modeling of electronic components(resistors,capacitors,inductors)in electronic devices,simplifying the calculation model,maintaining the accuracy of key characteristics,and improving simulation efficiency and accuracy.At the same time,a lumped port electromagnetic modeling method is implemented,which can reduce the complexity of the model,accurately describe the coupling effects between the system and the external environment,and support system-level simulation.Finally,the algorithms are verified using numerical simulation examples,demonstrating their efficiency and accuracy.Research on simulation analysis methods based on the Macroscopic Surface Transmission Conditions(GSTCs)and Hybrid Discontinuous Galerkin(HDG)methods.Firstly,starting from the basic theory of electromagnetics,the GSTCs model of the super surface is derived,which can be conveniently combined with the HDG method,and then a numerical analysis algorithm for the super surface is proposed.This method simplifies the calculation model by treating the super surface as a "boundary condition" while ensuring the required accuracy.Finally,the correctness of this method is verified through numerical simulation examples.Research on efficient dynamic simulation techniques for electronic devices,mainly including linear dynamic analysis and nonlinear dynamic analysis of electronic devices.Firstly,starting from linear elastic dynamics,the motion differential equations are transformed into the weak form of an equivalent integral,and then transformed into a stationary problem by the Hamiltonian principle.After finite element discretization,structural dynamic finite element equations are obtained.Moreover,this paper improves computational efficiency using p-type scalar multigrid preconditioning technology.Then,research on nonlinear dynamic simulation is conducted.Starting from the momentum equation and combining with the Lagrangian finite element method,the virtual power equation is derived,and after finite element discretization,explicit methods are used for solving,and Jaumann rate is used to update stress.Finally,a three-dimensional structural impact response solver IRS is developed.Research on thermal-force coupling simulation technology for electronic devices.Firstly,based on the basic principles of heat conduction,an in-depth analysis of threedimensional heat conduction problems is conducted,and further derivation of finite element formulas is performed,as well as in-depth research on boundary conditions and heat source application issues.On this basis,research on the basic theory of thermoelasticity is conducted,and the generalized motion equations when the object produces thermal deformation are derived.Discretization is performed using layered scalar basis functions,and p-type scalar multigrid preconditioning technology is introduced.A finite element code for thermal-force coupling analysis is developed,achieving efficient and accurate thermal-force coupling analysis of electronic devices.Research on multi-physics joint simulation technology for electronic devices.For the comprehensive simulation problem of multi-physics fields in electronic devices,a multi-physics joint simulation analysis scheme for electronic devices is proposed.Additionally,a grid-level coupling precise solution technology is proposed,achieving seamless docking of multi-field data,accurately and automatically realizing multi-physics field coupling simulation analysis.Furthermore,a model reshaping technology is proposed,which can reshape the deformation model and update the grid based on the deformation displacement of the calculation model,thereby improving simulation accuracy.Finally,combined with the research of the whole paper and CAE technology,a multi-physics field comprehensive simulation CAE software based on the finite element method—Kaiyang Electromagnetic Multi-physics Field Coupling Simulation Software—has been developed.The software has a friendly interactive interface,complete pre-and post-processing functions,and efficient and accurate solvers.The software can currently be used for analysis and solution of high-frequency electromagnetic simulation problems,thermal simulation problems,structural simulation problems,and multi-physics field coupling simulation problems of electronic devices.