• 제목/요약/키워드: air 제트 직기

검색결과 7건 처리시간 0.031초

에어제트 직기의 노즐 설계기술 (A brief introduction to nozzle design in air jet loom)

  • 송동주;구본감
    • 기계저널
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    • 제35권1호
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    • pp.36-45
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    • 1995
  • 주노즐내의 공기제트의 효율을 높이기 위해, 주노즐 제트 속도는 높을수록 높은 마찰력을 초래 하여 위사의 속도를 증가시킨다. 가속관의 길이가 증가하면 노즐출구에서의 공기의 속도와 난 류가 감소하며; 가속관의 직경이 증가할 때에는 공기속도가 감소하며 난류는 증가한다. 탱크압력, 가속관의 길이 등 유동조건에 따라 유동은 니들 끝과 가속관 출구에서 이중 초크(M=1)가 발 생할 수 있다. 에어가이드 직경과 노즐직경의 그 비율이 클수록 제트에 의한 유동의 비말동 반(entrainment)이 크게 된다. 실제 노즐직기내의 유동은 위사를 동반한 유동이므로 위와 같은 정성적인 설명에 위사의 물성치에 따른 고려를 반드시 하여야만 한다. 현장에서의 노즐설계는 노즐형상 자체의 영향은 물론 각종 위사의 물성치에 맞는 압축공기 압력 최적조건이 무엇인가를 찾는 일도 매우 중요하다.

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에어제트 직기에 가해지는 가진력 추정 (Indirect force identification of air-jet weaving machine infrequency domain)

  • 정의일;전두환;노석홍
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.238-241
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    • 2006
  • For the effective reduction of structural vibration level it is important to obtain the exciting force components. But, sometimes direct force measurement is infeasible due to the geometric limitation of sensor placement. In this case, indirect force identification becomes useful tool for obtaining input force information. In this paper, indirect force technique was applied to air-jet weaving machine and shows some numerical results.

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프로젝타일과 에어제트 직기특성이 의류용 모직물 물성에 미치는 영향(I) - 장력특성과 직기 메커니즘 - (Effect of the Projectile and the Air-jet Weaving Machine Characteristics on the Physical Properties of Worsted Fabrics for Garment(I) -Tension Characteristics & Loom Mechanism-)

  • 김승진;정기진
    • 한국의류산업학회지
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    • 제7권1호
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    • pp.101-105
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    • 2005
  • This study surveys the warp and weft tension differences between projectile and air-jet looms and analyses the mechanical properties of worsted fabrics for garment with relation of these loom characteristics using KES-FB system. The paper is divided by two parts. In the 1st paper, the worsted fabric is woven as 5 harness satin weave using 1/40 Nm sirofil worsted warp yarn and 1/30 Nm worsted weft yarn by projectile(Sulzer) and air-jet looms(Picanol PAT and OMNI), respectively. The weavability is also analysed by measuring warp tension variation according to the warp position and weft tension of 3 kinds of looms. The relationship between shed amount and the warp tension is surveyed, and the relationship between end breaks and warp and weft tensions is also discussed.

프로젝타일과 에어제트 직기특성이 의류용 모직물 물성에 미치는 영향(II) - 의류용 모직물 물성변화 - (Effect of the Projectile and the Air-jet Weaving Machine Characteristics on the Physical Properties of Worsted Fabrics for Garment(II) - Physical Properties of Worsted Fabrics for Garment -)

  • 김승진;정기진
    • 한국의류산업학회지
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    • 제7권1호
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    • pp.106-110
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    • 2005
  • This research surveys the mechanical properties of worsted fabrics for garment according to the loom characteristics and fabric positions with relation to the warp and weft weaving tensions on the projectile and air-jet looms, which is previously surveyed in the 1st paper. For this purpose, the grey fabrics are processed in dyeing and finishing processes. The mechanical properties of the finished fabrics are measured and discussed with relation to the warp and weft weaving tensions of projectile and air-jet looms and the variations of the fabric mechanical properties according to the fabric positions are also surveyed for investigating the homogeneity of the tailorability and fabric hand.

에어제트직기 주 노즐내 천음속 유동의 수치 해석적 연구 (A Numerical Analysis of Transonic Flows in an Axisymmetric Main Nozzle of Air-Jet Loom)

  • 오태훈;김상덕;송동주
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 1998년도 춘계 학술대회논문집
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    • pp.168-173
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    • 1998
  • A numerical analysis of axisymetric backward facing step main nozzle flow in air jet loom has been accomplished. To obtain basic design data for an optimum main nozzle for an air-jet loom and to predict the transonic/supersonic flow, a characteristic based upwind flux difference splitting compressible Navier-Stokes method has been used. The wall static pressure of the main nozzle and the flow velocity changes in the nozzle tube were analyzed by changing air tank pressures and acceleration tube lengths. The flow inside the nozzle experiences double choking one at the needle tip and the other at the acceleration tube exit at tank pressures over $4kg_f/cm^2$. The tank pressure $P_t$ leading to the critical condition depends on the acceleration tube length; i.e, $P_t$ is higher for longer acceleration tubes. The $P_t$ value required to bring the acceleration tube exit to the critical condition is nearly constant regardless of acceleration tube length. The round needle tip shape might lead to less total pressure loss when compared with step shape.

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