화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
Korean Journal of Rheology, Vol.5, No.1, 34-48, June, 1993
Export Citation
사출성형 모사에 있어서 벽면 경계조건 처리를 위한 선단 유동장 생성기법과 spline 곡선을 이용한 선단 격자 재구성
Frontal Flow Field Construction for Wall Boundary Condition Treatment and Frontal Remeshing Using Spline Curve in Injection Molding Simulation
정준호, 윤재륜
초록
최근 CAD/CAM의 발전과 더불어 사출성형공정은 여러 분야에 폭넓게 응용되고 있다. 사출성형공정은 크게 충전과정(filling stage), 냉각과정(cooling stage), 보압과정(packing stage)로 나누어 지는데, 이중 충전과정은 냉각과정과 보압과정에서 나타날 물리적인 현상과 최종 성형품의 기계적 성질에 중요한 영향을 끼치게 된다. 충전과정의 수치 해석 방법은 대표적으로 control volume method, branching flow method, transient moving boundary method로 구분된다. 본 연구에서는 격자의 형태를 양호하게 형성시키고 유동선단의 형태를 개선하기 위한 기법인 Spline 곡선을 이용한 선단 격자 재구성(frontal remeshing using spline curve)과, 수치해석에 소요되는 시간을 줄이기 위하여 벽면 경계조건 처리를 위한 선단 유동장 생성(frontal flow field construction for wall boundary condition treatment)기법을 개발하고 transient moving boundary method에 적용시켜 원형 평판과 인장 및 굽힘시편 그리고 두께가 변하는 사각 형상을 가진 캐비티에서의 충전과정을 수치해석하였다. 그 결과 압력 분포, 온도 분포, 속도장, 유동선단의 진전형태 등이 기존에 제출된 해석결과와 비교하여 볼 때 만족스러운 수치 해석 결과를 보였다.
With recent development of CAD/CAM, injection molding is widely used for net shape manufacturing. Injection molding process consists of three major stages such as filling, cooling, and packing. Among them, filling stage has a large effect on physical behavior of the other stages and the quality of final products. There are mainly three methods such as control volume method, branching flow method, and transient moving boundary method in numerical simulation of filling stage. In this study, frontal remeshing using spline curve and frontal flow field construction for wall boundary condition treatment be proposed for implementation of the transient moving boundary method. The former method made shape of the mesh better and improved predicted melt front line and the latter method decreased computation time for numerical analysis. Injection molding of a circular plate, tensile and bending specimen, and a rectangular plate with varialbe gap thickness was modelled by the proposed numerical simulation technique. As the result, pressure distribution, temperature profile, velocity vectors, and the melt front advancement were obtained and considered to be acceptable compared with reported experimental and numerical results.
Keywords:Injection Molding(사출성형);numerical analysis(수치해석)
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