• Title/Summary/Keyword: inner shape

Search Result 770, Processing Time 0.027 seconds

A Study on the Fluid Flow of Vortex Nozzle for Generating Micro-bubble (미세버블 발생용 보텍스 노즐의 유체유동에 대한 연구)

  • Yu, Seong-Hun;Park, Sang-Hee;Kang, Woo-Jin;Han, Seung-Wook
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.25 no.4_2
    • /
    • pp.637-644
    • /
    • 2022
  • In this study, the flow characteristics according to the shape of the vortex nozzle was studied by numerical analysis and the amount of microbubble generation was measured experimentally. The shape of the vortex nozzle is cylindrical, diffuser, and conical type. The axial fluid velocity in the induced tube gradually increased from the inlet to the outlet. In particular, the fluid velocity in the nozzle part increased rapidly. The velocity distribution of the fluid at the inlet of the induced tube showed that the flow rotates counterclockwise in the outer region and the inner center of the induced tube. At the outlet of the induced tube, the cylindrical and conical type showed rotational flow, and the diffuser type showed irregular turbulent flow. The dimensionless pressure ratio 𝜂 of the inner region of the induced tube was lower than that of the outer region. Also, 𝜂 near the outlet of the induced tube in cylindrical and conical type showed a similar tendency to the inlet area. At the outer region of inlet of induced tube, intense vorticity was observed on the wall and in lower region. At the inner region of inlet of induced tube, intense vorticity was observed on the inner wall of the induced tube and in the central region of the inlet of the induced tube. At the outlet of induced tube, in the case of the cylindrical and conical type, intense vorticity was observed near the inner wall, the diffuser type showed irregular strong vorticity inside the tube. The total number of bubbles measured was the most in the cylindrical type, and the microbubbles less than 50mm occurred the most in the conical type.

Fabrication and Static Bending Test in Ultra Light Inner Structured and Bonded(ISB) Panel Containing Repeated Inner Pyramidal Structure (피라미드 구조를 가지는 초경량 금속 내부구조 접합판재의 제작 및 특성평가)

  • 정창균;윤석준;성대용;양동열;안동규
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2004.10a
    • /
    • pp.483-486
    • /
    • 2004
  • Inner structured and bonded panel, or ISB Panel, as a kind of sandwich type panel, has metallic inner structures which have low relative density, because of their dimensional shape of metal between a pare of metal skin sheets or face sheets. In this work, ISB panels and inner structures formed as repeated pyramidal shapes are introduced. Pyramidal structures are formed easily with expanded metal sheet by the crimping process. Three kinds of pyramidal structures are made and used to fabricate test specimen. Through the multi-point electrical resistance welding, inner structures are bonded with skin sheet. 3-point bending tests are carried out to measure the bending stiffness of ISB panel and experimental results are discussed.

  • PDF

A Finite Element Modeling and Analyses of Laser Tailor-Welded Automotive Body (레이저 용접 차체의 유한 요소 모델링과 성형해석)

  • 김헌영;최광용;김관회;조원석
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 1997.03a
    • /
    • pp.31-36
    • /
    • 1997
  • Various methods of finite element modeling for welded part are examined and the stamping simulation of automotive body is presented by using the explicit finite element code PAM-STAMPTM. The process of stamping simulation is suggested step by step, and then the gravity, binder wrap, forming, trimming and springback of front door inner are analyzed. It shows good agreements with real product in the aspects of deformed shape and failure area. The door inner with laser-tailor welded blank is simulated, in which deformed shape, movement of welde line and formability are predicted.

  • PDF

Optimal design of Natural Fiber Composite Structure for Automobile

  • Lee, Haseung;Kong, Changduk;Park, Hyunbum
    • International Journal of Aerospace System Engineering
    • /
    • v.3 no.1
    • /
    • pp.21-24
    • /
    • 2016
  • In this study, a optimal design on the hood automotive using eco-friendly natural fiber composites is performed. The hood of an automobile is determined by dividing the Inner panel shape through optimization phase to outer panel and inner panel. It was performed to optimize the size of the thickness of the inner panel and the outer panel by applying a flax/epoxy composite materials. The optimized shape was evaluated for weight-lightening, stability and the pedestrian collision safety. Through the resin flow analysis are confirmed to molding possibility judgment of product.

A Study On Changes in the Shape of Collars and Necks of Korean Clothing (옷깃과 옷섶의 형태변화(形態變化)에 대한 연구(硏究) - 조선시대(朝鮮時代)의 저고리와 포(袍) -)

  • Paik, Kum-Hyun
    • Journal of the Korean Society of Costume
    • /
    • v.6
    • /
    • pp.105-119
    • /
    • 1982
  • This thesis is mainly about the changes of Garment's collar(옷깃) and outer collar (옷섶) which indicate the identification of dress history. Through the observations of some reports about important folk materials and genuine objects, the author has investigated and rearranged them focusing on Yi-Dynasty. (1400-1900) For the shape of the outer lapels(겉깃) of Korean Jacket(저고리) were used together Squar-Tray-Collar(목판깃), Sharped-Collar(칼깃), and Dang ko-Collar(당코깃) and coming to the end of inner lapels(안깃) formed squar-tray-collar. Squar-tray-collar and sharped-collar were mainly used together for the shape of the outer lapels of Korean overcoat(포). Dang ko-collar was seen only in two overcoat. Coming to the 18th centry, the outer lapels became round-edged like those of jackets, while the inner lapels formed squar-tray-collar. In the process of positional changes of the collar and outer collar of Korean jacket and overcoat, the outer lapels positioned outside the outer collar, or a part of width of collar's positioned upon the outer collar, or the whole outer lapels positioned inside the outer collar. And through these changes the current position of the outer lapels became settled in the end of the 19th centry. But the inner lapels did not undergo many changes compared with the outer ones, and their position was mainly outside the outer collar like those of current lapels. And the garment's collar and outer collar of jacket and overcoat became small while the width and length of breast-tie(고름) became large.

  • PDF

A Study on the Development of Protective Inner Wear for Lumbar Disc Disease Patients (Part I) -Analysis of Commercial Lumbar Pads and the Actual Wearing State of the Lumbar Pads- (허리디스크 환자를 위한 허리보호용 이너웨어 개발 연구(제1보) -시판 허리디스크 보조기 분석과 허리디스크 환자의 보조기 착용실태 조사-)

  • Kang, Hye-Jin;Jung, Myoung-Sook
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.40 no.3
    • /
    • pp.516-525
    • /
    • 2016
  • Lumbar discs are one of the first parts of the musculoskeletal system to age in the human body. Lumbar disc for females start to age at twenty years of age and completely age between fifty and sixty. The number of lumbar herniated intervertebral disc patients are increasing rapidly; however, studies on protective inner wear are insufficient. This study was conducted to develop protective inner wear equipment that retains an aesthetic appreciation of the body. The methods and procedures of this study are as follows. First, foreign and domestic lumbar pads were researched and analyzed by visiting medical shops and internet shopping malls that sell lumbar pads. Second, the survey was conducted on forty patients with disc disease in hospitals located in Seoul and surrounding suburbs. The following are the study results and observations. First, the lumbar pads selling on the market had a variety of designs, textiles, and fabrics. The result of the research was to develop additional inner protective equipment for lumbar herniated intervertebral disc patients. Second, the survey results of the forty patients with disc disease were that housewives were the most vulnerable. All patients had experience purchasing lumbar pads. The prevention of pain and stress were the most selected responses for the motivation to buy lumbar pads. Most individuals said that they used lumbar pads for less than 1 year. Dissatisfaction came from fabric, activity and design. 'Being uncomfortable to wear' was the most common complaint. 'Protection and how easy the clothes were to wear' were the most selected for the necessity of developments. The Inner wear shape was the most selected in shape. Except for six respondents, all favored the lumbar protective inner wear design.

Optimal Design of Metallic Sandwich Plates with Inner Dimpled Shell Subjected to 3-Point Bending (굽힘 하중을 받는 딤플형 금속 샌드위치판재의 최적설계)

  • Seong D.Y.;Jung C.G.;Yoon S.J.;Yang D.Y.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2005.06a
    • /
    • pp.702-705
    • /
    • 2005
  • Metallic sandwich plates with Inner dimpled shell subjected to 3-point bending have been analyzed and then optimized for minimum weight. Inner dimpled shells can be easily fabricated by press or roll with high quality precision and bonded with same material skin sheets by resistance welding or adhesive bonding process. Optimized shape of inner dimple is a hemispherical shell to minimize weight without failure, including face yielding, face buckling and inner dimple buckling. It is demonstrated that bending stiffness of sandwich plate is 2 or 3 times than solid plates with same strength

  • PDF

The Characteristics and its Change of Community Space in the Old Settlements of Cheongju City (도심 옛마을에 있어서 커뮤니티 공간의 특성 및 변화)

  • Kim, Tai-Young
    • Journal of the Korean Institute of Rural Architecture
    • /
    • v.15 no.4
    • /
    • pp.43-50
    • /
    • 2013
  • This study is to clarify the characteristics and its change of spatial elements for community focused on the existing 22 old settlements in urban area of Cheongju. These community spaces are mainly divided into three parts, that is central space, inner road, and blind alley(cul-de-sac). The transitional characteristics of them are as follows. Firstly, the characteristics of central spaces is lasting, but the function is influenced by changing times. The function of central spaces located at the entrance to the village had been reduced to adjustments to modern lifestyle, and currently changed into senior citizen community center, supermarket, and public area. Secondly, as the width of the existing inner roads passed through old settlements had been extended, they are changed into pedestrian and traffic road, but the shape and function of them have been maintained. When new roads passed through old settlements had been established, the shape of old inner roads is disappeared, and the function of them is changed into byway and alley. Thirdly, cul-de-sacs of old settlements have tended to create a sense of community, but new cul-de-sacs formed by lot division have been only changed to passage. When new roads are established and cul-de-sacs are changed into alleys, the community between individual households is lost.

A Study about Pipe Shape Inspection System for Computer Vision (컴퓨터 비젼을 이용한 파이프 형상 검사시스템에 관한 연구)

  • 김형석;이병룡;양순용;안경관;오현옥
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2003.06a
    • /
    • pp.946-950
    • /
    • 2003
  • In this paper, a computer-vision based pipe shape inspection algorithm is developed. The algorithm uses the modified Hough transformation and a line-scanning approach to identify the edge line and radius of the pipe image, from which the eccentricity and dimension of the pipe-end is calculated. Line and circle detection was performed using Laplace operator with input image, which are acquired from the front and side cameras. In order to minimize the memory usage and the processing time, a clustering method with the modified Hough transformation for line detection. The dimension of inner and outer radius of pipe is calculated by proposed line-scanning method. The method scans several lines along the X and Y axes, calculating the eccentricity of inner and outer circle. by which pipes with wrong end-shape can be classified removed.

  • PDF

A Study on the Shape of Beam Attached CFT inner-side for Developing Column's Performance (콘크리트충전 강관기둥의 성능향상을 위한 내면부착 beam의 형상 연구)

  • Lee, Dong-Un;Yun, Hyug-Gee;Kim, Dea-Geon
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2015.05a
    • /
    • pp.21-22
    • /
    • 2015
  • The CFT(Concrete Filled Tube) system has been developed to behave well in a structural performance such as stiffness, stress, ductility, fire resistance that is derived from its mechanical advantages of composite structure. There were number of studies about unprotected CFT columns for improving their fire resistance through reinforcing bars or plates being placed inside the steel tube. It was also known that reinforcing plates of flat type need stiffeners in a certain distance to avoid their buckling failure so it cost as much as their using consequentially. This paper is planned to test the work of beam elements attached inner side of CFT depending on its shape. More discussions on beam's design could be followed after some fire tests accordingly conducted within this project.

  • PDF