No abstract

Accurate prediction of the cure level of thermoset polymers is essential to simulate the thermomechanical behavior of polymeric thermoset sealants, which is strongly dependent on cure level. Conventional cure kinetics models, however, fail to accurately predict the cure levels of thermoset sealants subjected to a complex temperature program. Herein, we propose a new cure kinetics model that greatly enhances cure level predictability by considering temperature derivatives. The validity of our model was verified by simulating the thermomechanical behavior of a polymeric sealant using a user material subroutine (UMAT) of ABAQUS software. Experimental results from an appropriately designed thermomechanical test were compared with simulation results obtained from the UMAT.

No abstract

No abstract

: A kinematic analysis method has been used as analysis method for dynamic behavior of moving parts of vehicle, especially hood part. Such analysis method, however, has its limitations in terms of design technology, including, over travel of hood that occurs due to lack of considerations of compliance characteristics, such as flexible components of hood's weather strip and over slam bumper. Therefore, it is necessary to develop a modeling which reflects compliance of flexible components of hood and elastic characteristics of panel for improvement of design process. In this thesis, a finite element method as mentioned earlier, is developed to represent over travel of hood. Also optimization process applying sequential approximate optimization is suggested to prevent over travel. The over travel analysis method and optimization process, which are developed through the research, would make it possible to design with high quality and credibility. Furthermore, it is expected that the time for design would be reduced and the design quality also improved.