• 제목/요약/키워드: computational investigation

검색결과 728건 처리시간 0.024초

광섬유 대량생산시스템 이중 액상코팅공정의 점성소산 및 공정인자 영향성 해석연구 (Parametric Investigation on Double Layer Liquid Coating Process with Viscous Dissipation in Optical Fiber Mass Manufacturing System)

  • 김경진;박중윤
    • 반도체디스플레이기술학회지
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    • 제17권4호
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    • pp.80-85
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    • 2018
  • The present investigation on optical fiber mass manufacturing features the computational modeling and simulation on a double layer liquid coating process on glass fiber surface. The computational model employs a simplified geometry of typical fiber coating system which consists of primary and secondary coating dies along with secondary coating cup. The viscous dissipation in coating flow is incorporated into the double layer coating process simulations. Heavy temperature dependence of coating liquid viscosity is also considered in the model. The computational results found that the effects of viscous dissipation on both primary and secondary coating layer thicknesses are highly significant at higher drawing speed. Several important coating process parameters such as supply temperature and pressure of primary and secondary coating liquids are investigated and discussed in order to appreciate how those parameters affect the double layer coating layer thickness on fast moving glass fiber.

A Flow Analysis of a Refrigeration Warehouse where an Unusual Death of an Operator Occurred by Deficiency of Oxygen

  • Park, Chan-Seong;Moon, Jung-Eun;Kim, Yoon-Ho;Kim, Jin-Pyo
    • International Journal of Safety
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    • 제5권2호
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    • pp.29-33
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    • 2006
  • A numerical flow analysis of the case of a refrigeration warehouse where an unusual death of an operator occurred by deficiency of oxygen is performed by using STAR-CD program of the computational fluid dynamics (CFD) code. The refrigeration room of the warehouse for storing the fruits maintains an atmosphere of 95% nitrogen and 5% oxygen by volume. When the operator was found dead in the refrigeration room, the room was in normal operating conditions except for the fact that the auxiliary door had been left open. For the flow analysis, unsteady 3-dimensional natural convection with mass transfer is considered. The flow analysis result is compared with the oxygen concentration level measured against time during on-site investigation. The change in oxygen concentration level in the warehouse due to the opening of the auxiliary door is found to be negligible.

전투차량 흡기시스템의 압력손실에 관한 수치적 연구 (A Computational Study on the Pressure Loss of Intake System for the Combat Vehicle)

  • 문성목;안수홍;이경훈;우관제
    • 한국유체기계학회 논문집
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    • 제15권3호
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    • pp.25-31
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    • 2012
  • A computational study on the improvement of the pressure loss of intake system, which is located at engine manifold of the combat vehicle, has been conducted using a finite-volume-based, Reynolds-Averaged Navier-Stokes (RANS) solver. The computational result of the pressure loss through the air cleaner is in good agreement with equivalent experimental data. A parametric study was done for improving of the pressure loss of intake system over the baseline case. The effects of five primary parameters such as the height of inlet, the width of interconnection pipe, the shape of drain chamber and the diameter of filter housing were considered in this study. Consequently, this computational investigation can contribute to finding an optimal guideline for the idea of improvement in the pressure loss of intake system.