Graphically Driven Interactive Stress Reanalysis for Machine Elements in the Early Design Stage

In this work a new graphically driven interactive stress reanalysis finite element technique has been developed so that an engineer can easily carry out manual geometric changes in a machine element during the early design stage. The interface allow an engineer to model a machine element in the commercial finite element code ANSYS® and then modify part geometry graphically to see instantaneous graphical changes in the stress and displacement contour plots. A reanalysis technique is used to enhance the computational performance for solving the modified problem; with the aim of obtaining results of acceptable accuracy in as short a period of time in order to emphasize the interactive nature of the design process. Three case studies are considered to demonstrate the effectiveness of the prototype graphically driven reanalysis finite element technique. The finite element type considered is a plane stress four-node quadrilateral based on a homogenous, isotropic, linear elastic material. The first two problems consider a plate with hole and plate with fillets. These two examples demonstrate that by changing the hole and fillet size/shape, an engineer can manually obtain an optimum design based on the stress concentration factor, i.e. engineer-driven optimization process. Each case study considered multiple redesigns. A combined approximation reanalysis method is used to solve each redesigned problem. The third case study considers a support bracket. The goal is to design the cantilever portion of the bracket to have uniform strength and to minimize the stress concentration at the fillet. The major beneficiaries of the work will be engineers working in product development and validation of components and structures, which are subjected to mechanical loads. The scientific and technological relevance of this work applies not only to the early stage of design, but to a number of other applications areas in which benefits may accrue. A company may have needs for a rapid analysis and re-analysis tool for fatigue assessment of components manufactured slightly out of tolerance. Typically this needs to be carried out under a very restrictive time scale

APPROVED: Graphically Driven Interactive Stress Reanalysis for Machine Elements in the Early Design

In this work a new graphically driven interactive stress reanalysis finite element technique has been developed so that an engineer can easily carry out manual geometric changes in a machine element during the early design stage. The interface allow an engineer to model a machine element in the commercial finite element code ANSYS ® and then modify part geometry graphically to see instantaneous graphical changes in the stress and displacement contour plots. A reanalysis technique is used to enhance the computational performance for solving the modified problem; with the aim of obtaining results of acceptable accuracy in as short a period of time in order to emphasize the interactive nature of the design process. Three case studies are considered to demonstrate the effectiveness of the prototype graphically driven reanalysis finite element technique. The finite element type considered is a plane stress four-node quadrilateral based on a homogenous, isotropic, linear elastic material. The first two problems consider a plate with hole and plate with fillets. These two examples demonstrate that by changing the hole and fillet size/shape