• Title/Summary/Keyword: belt

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Turbulent Drag Reduction Using the Sliding-Belt Device (미끄러지는 벨트 장치를 이용한 난류 항력 감소)

  • Choi, Byunggui;Choi, Haecheon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.11
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    • pp.1481-1489
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    • 1999
  • The sliding-belt concept introduced by Bechert et al. (AIAA J., Vol. 34, pp. 1072~1074) is numerically applied to a turbulent boundary layer flow for the skin-friction reduction. The sliding belt is moved by the shear force exerted on the exposed surface of the belt without other dynamic energy input. The boundary condition at the sliding belt is developed from the force balance. Direct numerical simulations are performed for a few cases of belt configuration. In the ideal case where the mechanical losses associated with the belt can be ignored, the belt velocity increases until the integration of the shear stress over the belt surface becomes zero, resulting in zero skin friction on the belt. From practical consideration of losses occurred In the belt device, a few different belt velocities are given to the sliding belt. It is found that the amount of drag reduction is proportional to the belt velocity.

A Study on the Prediction Method of Belt Edge Separation due to the Belt Width Variation of a Tire (타이어의 Belt Width 변화에 따른 Belt Edge Separation 예측 방법에 관한 연구)

  • Kim Seong-Rae;Sung Ki-Deug;Kim Son-Joo;Cho Choon-Tack
    • Journal of the Korean Society for Precision Engineering
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    • v.23 no.8 s.185
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    • pp.137-144
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    • 2006
  • This study is concerned with the relation between steelbelt width and belt edge separation of a tire. Belt edge separation causes tire burst and threatens passenger's safety. For the reason, it is important to predict durability caused by belt edge separation in the early stage of the tire structure design. Usually, passenger car tires have two layers of steelbelts having opposite steel cord's angles, which makes a shear behaviour between each belt layer. Shear behaviour is one of reason to cause belt edge separation. In this study, to predict belt edge separation, we suggested the prediction method of belt edge separation and evaluated the effect of steelbelt width on the belt edge separation using FEM. We also studied on main parameters to affect shear behaviour at the belt edge area.

Analysis of OHC drive timing belt system behavior for fixed and automatic tensioner (고정 및 자동장력식 텐셔너에 대한 OHC 구동 타이밍 벨트 시스템의 거동해석)

  • 김현수;이인환;여창기
    • Journal of the korean Society of Automotive Engineers
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    • v.14 no.4
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    • pp.79-89
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    • 1992
  • The behavior of belt tension in OHC drive timing belt system was investigated analytically and experimentally for (1)fixed and (2)automatic tensioner. From the numerical results it was found that the automatic tensioner makes the belt tension larger than those of the fixed tensioner. When the initial belt tension decreased due to the belt elongation, the belt tension of the fixed tensioner could decrease to near zero while the belt tension for the automatic tensioner maintained above zero by the tensioner spring. The mean valve and the difference between the maximum and the minimum belt tension for the automatic tensioner increased compared with those of the fixed tensioner. Also, the numerical results for a hydraulic tensioner showed that the hydraulic tensioner has the good parts of both tensioners; i.e., thesmaller amplitude in belt tension and the higher mean tension. Experimental results for the automatic and fixed tensioner of the OHC timing belt system were in agreement with the theoretical results.

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A Study on the Belt width and Separation of Tire using FEM (FEM을 이용한 Belt Width와 Separation에 관한 연구)

  • Kim S.R.;Sung K.D.;Kim S.S.;Cho C.T.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.2006-2010
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    • 2005
  • This study is concerned with the relation between steelbelt and belt edge separation. Belt edge separation causes tire burst and threatens passenger's safety. For that reason, it is important to predict durability caused by belt edge separation first in tire structure design step. In this study, to predict belt edge separation, we suggest the prediction method of belt edge separation and evaluate the effect of steelbelt width on the belt edge separation using FEM. We study on analysis parameter also to do exact estimation about the shear behaviour of belt edge area.

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Seat Belt Usage Rate and Unconscious Behavior in the Fastening Process (안전벨트 착용과정에서 무의식적 행위와 착용비율)

  • Hong, Seung-Kweon
    • Journal of the Ergonomics Society of Korea
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    • v.29 no.6
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    • pp.959-964
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    • 2010
  • Seat belt is an important means to protect drivers and passengers from the damages by car accidents. Many ways to increase the seat belt wearing rate have been proposed through human factors researches. The primary ways to increase seat belt use rate have emphasized the intention-behavior cycle. This study focused on the gap between intention and behavior. The gap may be bridged by the habit for seat belt use behavior. Divers following a desirable car starting sequence, from sitting on the chair, fastening seat belt, starting engine to moving a car, reported that higher belt wearing rate and unconscious behavior (automated response). That is, the habitualized procedure knowledge prevented drivers from forgetting to fasten their seat belt. The reminder systems such as warning light and warning sound could not significantly give an influence in remembering to fasten seat belt. In order to increase the seat belt use rate, the desirable car starting procedure should be included in the driving education program.

Development of Conveyor Belt Monitoring System (컨베이어 벨트상태 모니터링 시스템 개발)

  • 유재상
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.436-436
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    • 2000
  • In order to monitor the belt from being damaged by impact of large lump of materials in ores being transported on conveyor belt, we developed a conveyor belt monitoring system using vision. By the information such as the position and size of the damage of belt obtained by vision system, it is expected that not only the span of belt life will be lengthened, but also this system can enable operators to plan scheduled maintenance and prevent the enlargement of damaged parts in conveyor belt at an early stage

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Analysis of belt behavior for a metal V-belt CVT (금속 V-벨트 CVT의 벨트거동 해석)

  • 김현수;이재신
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.2
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    • pp.557-566
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    • 1991
  • The metal V-belt behavior of a continuously variable transmission was investigated analytically and experimentally. Numerical results showed that nondimensional belt radial displacement increased in the radial inward direction for the driven pulley, while that of the driver pulley increased for the first 90 degrees of the active are and decreased with the increasing torque load. Experimental results for the belt radial displacement were in good agreement with the theoretical results. However, the absolute magnitude of the belt radial displacement was so small that the change in the belt displacement could not be measured in the experimental range except for the inlet region of the driven pulley, where the radial inward displacement was observed due to the effect of bending moment. The speed ratio-axial force relationship derived from the belt behavior analysis also showed god agreement with the experiment.

Study on Continuously Variable System Using to Centrifugal Belt Pulley

  • Do, Hyung-jin;Youm, Kwang-Wook
    • International journal of advanced smart convergence
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    • v.9 no.1
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    • pp.10-18
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    • 2020
  • In the case of a belt-pulley type CVT that transmits a driving force by using a variable pulley and a metal belt, slippage occurs due to transmission of power by using a belt, which results in a decrease in efficiency. Therefore, in this study, the rails were machined on the plate surface of the pulley to reduce the friction and slip between the belt and the pulley while applying the characteristics of the CVT. As the plate is rotated by the shape of the rail, a centrifugal belt pulley type continuously variable transmission system which shifts while varying the radius of rotation of the belt that transmits power is studied. Accordingly, the structure of the pulley was designed and the centrifugal belt pulley type continuously variable transmission was Manufactured. In addition, to verify the suitability of the manufactured transmission, the power transmission efficiency was monitored by establishing an interface with the controller. The structural analysis of the plate proved the suitability of the centrifugal belt pulley type continuously variable transmission.

Behavior of Belt Running over the Rollers (롤러 위를 주행하는 벨트의 거동)

  • 윤여훈;윤준현
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.05a
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    • pp.900-905
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    • 2004
  • Development of color printer, postal classification machine, ATM and so on requires higher moving performance of the flat belt. Skew of the flat belt running over misaligned roller has a bad effect on performances of media transport. The vibration of loose side of belt causes the escape of the belt from roller and the drop of velocity of driven roller after the start of driving roller revolution. The skew of flat belt is investigated by FEM and dynamic simulation. FEM results show parameters which affect the skew of belt and match with dynamic results qualitatively. The shape of loose side of belt can be found by dynamic simulation. Increase of the acceleration time and initial tension have diminished the unstable movement of the loose side of belt.

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Belt Tension Distribution for Belt Contact Abrasive Belt Drive (벨트접촉식 연삭 벨트구동의 벨트 장력 분포)

  • 임영호;김현수;안효원
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.13 no.5
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    • pp.837-846
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    • 1989
  • Belt tension distribution for an abrasive blet grinding was investigated analytically and experimentally for (1) slack side and (2) tight side blet grinding. Classical Eytelwein equation was used to predict the belt tension distribution with dividing contact angles into (1) inactive and (2) active angles. General friction theory was modified based on the friction force between the belt and the support in the grinding contact area that was obtained by experiments. It was found that analytical results were in good agreement with the experimental results. Also, the tight side belt grinding was recommended since it could carry out more grinding load than that of slack side belt grinding.