superplastic materials show a very high ductility. this is due to both peculiar process conditions and material intrinsic characteristics. however, a number of superplastic materials are subjected to cavitation during superplastic deformation. evidently, extensive cavitation imposes significant limitations on their commercial application. the deformation and failure of superplastic sheet metals...

this paper is about discrete sensitivity analysis. a triangular bending element with constant moment and six degrees of freedom is used. the required derivatives for sensitivity analysis are calculated explicitly. these formulations, finite element method and sequential linear programming are utilized to find shape optimization of plate bending structures. the numerical examples, which show the...

this paper presents an overview of model updating and particularly its application for updating of frame model. in this article a mathematical model of the frame was produced with finite element method. the frame was subjected to hammer modal testing. then the results of the modal testing were compared with those predicted with the model. this comparison revealed discrepancies between these two...

the theory of contact mechanics deals with stresses and deformations which arise when the surfaces of two solid bodies are brought into contact. in elastic deformation contact occurs over a finite area. a regular method for determining the dimensions of this area is hertz contact model. appearance of atomic force microscope results in introduction of contact mechanics into biology. low elastici...

Foreign object damage (FOD) occurs when hard, millimeter-sized objects such as gravel or sand and even the pieces of the engine components are ingested into aircraft jet engines. Particles impacting blades produce small indentation craters which can become sites for fatigue crack initiation, severely limiting the lifetime of the blade. In this study, the impact on the edge of a thin plate is in...

the concepts of structural optimization was introduced about sixty years ago. smiths from the university of los angeles (california) for the first time has offered the combination of finite element method and optimization techniques to design optimum structures (1960). at present time, this techniques are generally understood and many softwares for this perpose have been developed. in this pape...

We describe a hybrid method which combines the boundary element method (BEM) and the finite element method (FEM) to compute circuit models for layout dependent capacitances. The method can handle irregularities in the stratification of the layout of the integrated circuits (IC’s). New in the method are the models for the interface between the regions where the BEM and the FEM are applied. We sh...

this paper presents a method for diagnosis of eccentricity fault in a switched-reluctance motor (srm) during offline and standstill modes. in this method, the fault signature is differential induced voltage (div) achieved by injecting diagnostic pulses to the motor windings. it will be demonstrated by means of results that there is a correlation between differential induced voltage and eccentri...

one of the bellows producing method is hydroforming process .whereas some factor of hydroforming process specially internal pressure affects on final characteristics produced bellows such as bursting, wrinkling and wall thickness distribution. in this paper the effect of internal pressure factor in final quality of produced bellows will be investigated. in simulation of process, abaqus/explicit...