식용 옥수수 수확기는 수확 시 옥수수 이삭의 손상율을 결정하는 탈과 시스템이 중요하다. 탈과 시스템을 개발하기 위해서는 탈과 시스템의 손상율에 영향을 미치는 주요 설계 변수를 구명해야 하고, 설계 변수의 영향 분석에는 시뮬레이션 기법이 많이 사용되고 있다. 본 연구의 목적은 탈과 시스템의 시뮬레이션 해석에 사용할 옥수수 줄기에 대한 이산요소 모델을 개발하는 것이다. 식용 옥수수의 특성을 고려하기 위하여 옥수수 줄기의 물리적 특성을 분석하였으며, 만능재료시험기를 이용한 압축 시험과 3점 굽힘 시험을 통하여 역학적 특성을 확인하였다. 또한, 옥수수 줄기의 이산요소 모델은 접촉 모델과 결합 모델로 구현하였고, 매개변수 연구를 통해 이산요소 모델의 주요 파라미터를 도출하였으며, 시험 결과와 비교하여 개발된 이산요소 모델을 검증하였다. 본 연구로부터 개발된 옥수수 줄기 모델은 탈과 시스템의 시뮬레이션에 활용된다.
four kinds of models designed by the basis of British industrial standard and ISO international standard in this study. Energy release rates at mode 1 are investigated by the fatigue analysis of aluminum foam TDCB model bonded with adhesive. These analysis models are compared each other by classifying four models into m values with 2, 2.5, 3 and 3.5. The value of m as the gradient of model is represented with the function of crack length(a) and height of model(h). Through the correlation relation, the fracture behavior of bonded material is analyzed and these analysis results can be applied to composite structures of various areas. Mechanical property and fracture toughness of composite material are also analyzed in this study.
This study aims to analyze the structural behavior on TDCB models bonded adhesively with aluminum foam composite. These simulation models are designed on the basis of British industrial and ISO standards. The variable of configuration factor(m) is set up to investigate the fracture toughness of bonded joint due to the volume of material. Equivalent stress, deformation energy, pressure at bonded part, reaction force-crack length, energy release rate-crack length are obtained by this analysis. Through the data of this study, the fracture behavior can be analyzed by applying the practical composite structure bonded with aluminum foam and the mechanical property can be understood.
Aluminum foam with the property as the excellent impact absorption has been widely used recently. It is necessary to study fracture energy due to fracture toughness by the use of adhesive joint at aluminum foam. This study aims at strength evaluation about adhesive joint on aluminum foam and the fracture of bonded DCB model with this material property is analyzed by simulation. These models are designed by differing in height on the basis of British industrial and ISO standards. As the value of height at model is higher, bonded part is separated to the end. By comparing some analysis results with experimental data, these data could agree with each other. By the verification with experimental results, these all simulation results in this study can be applied on real composite structure with aluminum foam material effectively. The fracture behavior and mechanical property can also be examined by this study.