• Title/Summary/Keyword: 비강

Search Result 597, Processing Time 0.03 seconds

A Study on Improving Fatigue Life for Composite Cylinder with Seamless Integrated Liner (이음매 없는 일체형 라이너를 갖는 복합재 압력용기의 피로수명 향상에 대한 연구)

  • Kim, Hyo-Joon
    • Journal of the Korean Institute of Gas
    • /
    • v.17 no.6
    • /
    • pp.46-51
    • /
    • 2013
  • Composite cylinder is used by hydrogen fuel cell vehicles and natural gas vehicles because of high specific modulus, specific strength and fatigue resistance. composite cylinder has a seamless integrated liner and it is fully overwrapped with structural fibers of high strength carbon fibers in an epoxy matrix. In this study, filament winding pattern and autofrettage pressure design technique are presented considering structural weakness of knuckle and compressive residual stress. Presented methodology is verified by pressure cycling test of composite cylinders.

Particle Image Velocimetry Measurements in Nasal Airflow (코 내부 유로(비강) 내부 유동의 PIV해석)

  • Kim, Sung-Kyun
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.26 no.6
    • /
    • pp.811-816
    • /
    • 2002
  • For the first time, airflow in the nasal cavity of a normal Korean adult is investigated experimentally by PIV measurement. Nasal airflow can be subdivided into two interrelated categories; nasal airflow resistance and heat and mass transfer between the air stream and the walls of the nasal cavity. In this study, thanks to a new method for the model casting by a combination of the rapid prototyping and curing of clear silicone. a transparent rectangular box containing the complex nasal cavity can be made fur PIV experiments. The CBC PIV algorithm is used for analysis. Average and RMS distributions are obtained for inspirational and expiration nasal airflows. Data fer the airflow at the end of meatuses are obtained for the first time. Comparisons between western and Korean nasal airflows are appreciated. Due to the difference in geometry of the frontal part of nasal cavity, the flow near nares shows the difference.

Design and Fabrication of Composite Sandwich Payload Platform and Strut Tubes for Satellite Main Body Structures (인공위성 본체 복합재료 샌드위치 플랫폼 및 튜브 스트럿 구조물의 설계 및 제작)

  • Roh, Hui-Seok;Choi, Heung-Seop;Ha, Jae-Seon;Son, Won-Gi;Kim, Cheol;Lee, Ju-Hun
    • Proceedings of the Korean Society For Composite Materials Conference
    • /
    • 2002.10a
    • /
    • pp.228-232
    • /
    • 2002
  • 본 연구에서는 다목적 실용위성 2호기에 적용된 금속 구조물 중 알루미늄 샌드위치 패널 구조인 탑재체 플랫폼과 튜브 스트럿(tube strut) 구조에 복합재료 응용기술을 적용하였다. 복합재료 구조로의 대체 설계에서도 관성하중 및 음향진동등과 같은 극심한 발사환경과 더불어 운용하게 될 우주 열환경을 고려하였다. 연구의 목적은 금속소재보다 비강도, 비강성이 우수한 복합재료를 위성 구조물에 사용함으로써 무게를 경량화함에 있다.

  • PDF

PIV Measurement on Airflows in the Abnormal Nasal Cavity with the Adenoid Vegetation (아데노이드 비대증에 의한 비정상 비강 내 유동의 PIV해석)

  • Kim, Sung-Kyun;Son, Young-Rak
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.27 no.4
    • /
    • pp.518-523
    • /
    • 2003
  • Airflow in the nasal cavity of Korean adults is investigated experimentally by PIV measurement. Quantitative data for normal and abnormal nasal cavities with adenoid vegetation are obtained. The CBC PIV algorithm with window offset is used for PIV flow analysis. Average and RMS distributions are obtained for inspirational and expirational nasal airflows. Comparisons between western and Korean nasal airflows are appreciated. Due to the difference in geometry of the frontal part of nasal cavity, the flow near nares shows the difference. For the joint research on nasal deceases, PIV measurements of nasal airflow for nasal cavities with 50% and 70% adenoid vegetation are conducted for the first time. Comparisons in nasal airflows for both normal and abnormal cases are also appreciated.