The finite element analysis of the fretting behavior between a cylinder block and a main bearing cap is presented. The stresses, relative fretting slip, frettin g friction work parameter W and crack initiation locatio...The finite element analysis of the fretting behavior between a cylinder block and a main bearing cap is presented. The stresses, relative fretting slip, frettin g friction work parameter W and crack initiation location parameter Gon the fretting contact surface of the cylinder block are obtained and analyzed. It shows that the fretting fatigue problem of the cylinder block can be quantitat ively explained by WorG. The effects of pretightening force, friction factor and material combination of the cylinder block and the main bearing cap are studied. The computational results indicate that the fretting fatigue of the cylinder block can be allayed by increasing the elastic modulus of the cylinder block, but not by changing the other two factors.展开更多
A contact bolt model is proposed as a new modeling technique to investigate the complex structure with bolted joints for modal analysis and compared with the coupled bolt model, and the test results are given. Among t...A contact bolt model is proposed as a new modeling technique to investigate the complex structure with bolted joints for modal analysis and compared with the coupled bolt model, and the test results are given. Among these models, the coupled bolt model provides the best accurate responses compared with the experimental results. The contact bolt model shows the best effectiveness and usefulness in view of operational time. The bolt models proposed in this study are adopted for a dynamic characteristic analysis of a large diesel engine consisting of several parts which are connected by many bolts. The dynamic behavior of the entire engine structure was investigated by experiment. The coupled bolt model and the contact bolt model were applied to model the assembly of engine with high preload. The experimental results are in good agreement with the finite element method （FEM） results. Compared with the other models, the contact bolt model presented in this paper is more effective and useful in view of operational time and experience of analysts.展开更多
At present, the mechanics theories studying softrock engineering generally depend onlinear small-deformation hypothesis of chosital mechanics. Although these theorics can be considered with the physical non-linear fea...At present, the mechanics theories studying softrock engineering generally depend onlinear small-deformation hypothesis of chosital mechanics. Although these theorics can be considered with the physical non-linear features of softrock, it is still an approximate theory of geometricsmall-deformation. Because of the specific characteristics of medium environment, the problem ofsoftrock engineering should be thought as large deformation. This article wili prove the advantagesof large deformation theory in solving softrock problem with an example of the No. 2 pit of NalongCoal Mine. This will provide a beneficai method for the studying of large deformation mechanics ofsoftrock engineering.展开更多
A new model is proposed to improve the efficiency of structural modeling. In this model, the bridge structural components are expressed with component description, parametric description and geometric description in a...A new model is proposed to improve the efficiency of structural modeling. In this model, the bridge structural components are expressed with component description, parametric description and geometric description in a software system. This model provides both convenience and flexibility for users in structural modeling process. The object-oriented method is applied in the model implementation. A bridge analysis preprocessor is developed on the basis of this model. It provides an effective way for bridge modeling.展开更多
Based on the coupled boundary element method-finite element method （BEM-FEM） method and the acoustic transfer vector （ATV） technology, BEM/FEM model is proposed for a Vtype eight cylinders engine acoustic radiatio...Based on the coupled boundary element method-finite element method （BEM-FEM） method and the acoustic transfer vector （ATV） technology, BEM/FEM model is proposed for a Vtype eight cylinders engine acoustic radiation simulating analysis under semi-anechoic condition. Acoustic radiation power, field points sound pressure level and panel contributions are calculated by acoustic radiation response analysis. Additionally, based on the engine acoustic performance, different acoustic behaviors of engine are studied by changing engine materials, oil pan structures as well as geometry parameters. The acoustic performance of this engine is predicted and the influence of material, structural and geometry parameters on engine radiated noise are generalized. The principle will guide the design and optimization of the engine prototype in further work.展开更多
Considering the stochastic spatial variation of geotechnical parameters over the slope, a Stochastic Finite Element Method (SFEM) is established based on the combination of the Shear Strength Reduction (SSR) concept a...Considering the stochastic spatial variation of geotechnical parameters over the slope, a Stochastic Finite Element Method (SFEM) is established based on the combination of the Shear Strength Reduction (SSR) concept and quasi-Monte Carlo simulation. The shear strength reduction FEM is superior to the slice method based on the limit equilibrium theory in many ways, so it will be more powerful to assess the reliability of global slope stability when combined with probability theory. To illustrate the performance of the proposed method, it is applied to an example of simple slope. The results of simulation show that the proposed method is effective to perform the reliability analysis of global slope stability without presupposing a potential slip surface.展开更多
文摘The finite element analysis of the fretting behavior between a cylinder block and a main bearing cap is presented. The stresses, relative fretting slip, frettin g friction work parameter W and crack initiation location parameter Gon the fretting contact surface of the cylinder block are obtained and analyzed. It shows that the fretting fatigue problem of the cylinder block can be quantitat ively explained by WorG. The effects of pretightening force, friction factor and material combination of the cylinder block and the main bearing cap are studied. The computational results indicate that the fretting fatigue of the cylinder block can be allayed by increasing the elastic modulus of the cylinder block, but not by changing the other two factors.
基金Sponsored by the Ministerial Level Foundation(40402020105)
文摘A contact bolt model is proposed as a new modeling technique to investigate the complex structure with bolted joints for modal analysis and compared with the coupled bolt model, and the test results are given. Among these models, the coupled bolt model provides the best accurate responses compared with the experimental results. The contact bolt model shows the best effectiveness and usefulness in view of operational time. The bolt models proposed in this study are adopted for a dynamic characteristic analysis of a large diesel engine consisting of several parts which are connected by many bolts. The dynamic behavior of the entire engine structure was investigated by experiment. The coupled bolt model and the contact bolt model were applied to model the assembly of engine with high preload. The experimental results are in good agreement with the finite element method （FEM） results. Compared with the other models, the contact bolt model presented in this paper is more effective and useful in view of operational time and experience of analysts.
文摘At present, the mechanics theories studying softrock engineering generally depend onlinear small-deformation hypothesis of chosital mechanics. Although these theorics can be considered with the physical non-linear features of softrock, it is still an approximate theory of geometricsmall-deformation. Because of the specific characteristics of medium environment, the problem ofsoftrock engineering should be thought as large deformation. This article wili prove the advantagesof large deformation theory in solving softrock problem with an example of the No. 2 pit of NalongCoal Mine. This will provide a beneficai method for the studying of large deformation mechanics ofsoftrock engineering.
文摘A new model is proposed to improve the efficiency of structural modeling. In this model, the bridge structural components are expressed with component description, parametric description and geometric description in a software system. This model provides both convenience and flexibility for users in structural modeling process. The object-oriented method is applied in the model implementation. A bridge analysis preprocessor is developed on the basis of this model. It provides an effective way for bridge modeling.
基金Supported by the Ministry level advanced research project(40402040108)
文摘Based on the coupled boundary element method-finite element method （BEM-FEM） method and the acoustic transfer vector （ATV） technology, BEM/FEM model is proposed for a Vtype eight cylinders engine acoustic radiation simulating analysis under semi-anechoic condition. Acoustic radiation power, field points sound pressure level and panel contributions are calculated by acoustic radiation response analysis. Additionally, based on the engine acoustic performance, different acoustic behaviors of engine are studied by changing engine materials, oil pan structures as well as geometry parameters. The acoustic performance of this engine is predicted and the influence of material, structural and geometry parameters on engine radiated noise are generalized. The principle will guide the design and optimization of the engine prototype in further work.
文摘Considering the stochastic spatial variation of geotechnical parameters over the slope, a Stochastic Finite Element Method (SFEM) is established based on the combination of the Shear Strength Reduction (SSR) concept and quasi-Monte Carlo simulation. The shear strength reduction FEM is superior to the slice method based on the limit equilibrium theory in many ways, so it will be more powerful to assess the reliability of global slope stability when combined with probability theory. To illustrate the performance of the proposed method, it is applied to an example of simple slope. The results of simulation show that the proposed method is effective to perform the reliability analysis of global slope stability without presupposing a potential slip surface.
