• 제목/요약/키워드: tangential force

검색결과 171건 처리시간 0.028초

종동력을 받는 외팔보의 진동특성에 미치는 세장비의 영향 (Effects of Slenderness ratio on Dynamic Behavior of Cantilever Beam Subjected to Follower Force)

  • 손인수;윤한익;안태수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2008년도 춘계학술대회논문집
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    • pp.575-578
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    • 2008
  • In this paper, the purpose is to investigate the stability and variation of natural frequency of a Timoshenko cantilever beam subjected to follower force and tip mass. In addition, an analysis of the flutter instability(flutter critical follower force) of a cantilever beam as slenderness ratio is investigated. The governing differential equations of a Timoshenko beam subjected to an end tangential follower force is derived via Hamilton;s principle. The two coupled governing differential equations are reduced to one fourth order ordinary differential equation in terms of the flexural displacement. Finally, the influence of the slenderness ratio and tip mass on the critical follower force and the natural frequency of a Timoshenko beam are investigated.

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비접촉 회전 스테이지에의 구동 원리로서의 횡자속 원주형 유도 방법 (Transverse flux circumferential induction method as a driving principle of the contact-free revolving stage)

  • 김효준;정광석
    • 한국정밀공학회지
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    • 제22권10호
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    • pp.72-79
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    • 2005
  • Compared with linear induction principle, the transverse flux circumferential induction principle is suggested as a driving mechanism of the revolving stage, which can rotate contactlessly without any supporting structure. The stage realizes the integrated motion of levitation, rotation, and planar perturbation, using the two-axis forces, normally directed force of the air-gap and tangential force, of the induction drivers mounted on the stator uniformly. In this paper, the force generating mechanism of the stage is described in detail. First, the various core shapes generating the transverse flux are analyzed to guarantee the proper thrust force. And the vector force intensity of the circumferential induction driver constituting the stage is compared with that of the linear induction driver. Especially it is shown that the magnetic force of the suggested system can be modeled with the linear equivalent model, including the test verification.

종동력을 받는 첨단질량을 갖는 외말보의 안전성에 관한 실험적 연구 (Experimental Study on the Stability of the Cantilever Beam with Tip Mass Subjected to a Follower Force)

  • 노광춘;박영필
    • 대한기계학회논문집
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    • 제10권2호
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    • pp.183-187
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    • 1986
  • 본 연구에서 종동력을 받는 첨단질량을 갖는 외팔보의 동적 안정성을 연구 하기 위해 접선 종동력을 전자석의 자기력에 의해 만들었으며, 이 비보존 종동력하에 서 보의 고유진동수의 변화와 임계하중에 대해 이론과 실험을 비교하였다.

경사 종동력을 받는 티모센코 보의 안정성에 미치는 크랙의 영향 (Effects of Crack on Stability of Timoshenko Beams Subjected to Subtangential Follower Force)

  • 손인수;윤한익
    • 한국소음진동공학회논문집
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    • 제18권12호
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    • pp.1327-1334
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    • 2008
  • In this paper, the purpose is to investigate the stability of cracked Timoshenko cantilever beams subjected to subtangential follower force. In addition, an analysis of the instability(critical follower force of flutter and divergence) of a cracked beam as slenderness ratio and subtangential coefficient is investigated. The governing differential equations of a Timoshenko beam subjected to an end tangential follower force is derived via Hamilton's principle. The crack is assumed to be in the first mode of fracture and to be always opened during the vibrations. The results of this study will contribute to the safety test and stability estimation of structures of a cracked beam subjected to subtangential follower force.

정면밀리에서 공구경사각을 고려한 비절삭저항 예측 (Prediction of Specific Cutting Pressure in Face Milling Considering Tool Rake Angles)

  • 류시형;주종남
    • 한국정밀공학회지
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    • 제14권2호
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    • pp.169-177
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    • 1997
  • In this study, investigated are the effects of tool rake angles and the change of cutting conditions on the specific cutting pressure in face milling. The cutting force in face milling is predicted from the double cutting edge model in3-dimensional cutting. Conventional specific cutting pressure model is modified by considering the variation of tool rake angles. Effectiveness of the modified cutting force model is verified by the experiments using special face milling cutters with different cutter pockets and various rake angles. From the comparison of the presented model and the specific cutting pressure, it is shown that the axial force can be predicted by the tangential force, radial force and geometric conditions. Also, the rela- tionship between specific cutting pressure and cutting conditions including feedrate, cutting velocity and depth of cut is studied.

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이온질화 처리강의 마모현상 분석에 관한 연구 (Study on the Analysis of Wear Phenomena of Ion-Nitrided Steel)

  • 조규식
    • Tribology and Lubricants
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    • 제13권1호
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    • pp.42-52
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    • 1997
  • This paper deals with wear characteristics of ion-nitrided metal theoretically and experimentally in order to analysis of wear phenomena. Wear tests show that compound layer of ion-nitrided metal reduces wear rate when the applied wear load is mall. However, as th load becomes large, the existence of compound layer tends to increase wear rate. The residual stress at the surface of ion-nitrided metal is measured, and the internal stress distribution is calculated when the normal and tangential forces are applied to the surface of metal. Compressive residual stress is largeest at the compound layer, and decreases as the depth from the surface increases. Calculation shows that the maximum stress exists at a certain depth from the surface when normal and tangential force are applied, and that the larger the wear load is the deeper the location of maximum stress becomes. In the analysis, it is found that under small applied wear load the critical depth, where voids and cracks may be created and propagated, is located at the compound layer, as the adhesive wear, where hardness is an important factor, is created the existence of compound layer reduces the amount of wear. When the load becomes large the critical depth is located below the compound layer, and delamination, which may be explained by surface deformation, crack nucleation and propagation, is created, and the existence of compound layer increases wear rate.

연삭 벨트-풀리간의 내접촉 특성에 대한 연구 (A Study on the Inside Contact Characteristics Between Abrasive Belt and Pulley)

  • 김현수
    • 대한기계학회논문집
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    • 제12권3호
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    • pp.457-465
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    • 1988
  • 본 연구에서는 벨트 연삭시 즉 집중하중을 받는 평벨트 구동에서 벨트와 풀리 사이의 내접촉 특성을 구하고자 하였다.준 정적평형(quasi-static equilibrium) 상 태에서 벨트구동계의 이론적 해석을 하여 집중하중점을 포함한 벨트-풀리 전접촉구간 에서 벨트장력분포를 구하고 이 결과를 실험치와 비교하였다. 본 연구에서는 집중하 중점 보다는, 집중하중의 벨트-풀리 전접촉구간에 대한 영향을 밝히는데 주안점을 두 었다.

타이어 공동의 공명에 의한 차량 실내음 전달경로 연구 (Study on Interior Noise Transfer Path Analysis by Tire Cavity Resonance)

  • 이상주;강현석
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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    • pp.129-133
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    • 2005
  • Vibration transmitted through rolling tire is a major source of road noise in vehicle interior noise on the range of low frequency.($0{\sim}500Hz$) Among various road noises, tire cavity noise has very peak on $200{\sim}250Hz$. And generally it is generated by cavity resonance of tire. In this paper, tire cut-sample is used to calculate the tire cavity frequency. Cavity resonance frequency of tire is measured through vertical/tangential forces at load cell of axle using drum cleat impact. This method is useful to find cavity peak because measured forces do not have complex peaks. And changing the test conditions (air inflation, loads), tire cavity resonance characteristics are identified. Finally, vehicle interior noise is measured as tire/vehicle are changing. As difference of tire vertical force is bigger, interior noise level is higher at cavity frequency. Also we can assume that vehicle sensitivity is important factor at tire cavity noise.

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기체-액체 원심분리기의 설계를 위한 매개변수 연구 (A Parametric Study for the Design of Gas-Liquid Centrifugal Separator)

  • ;오성진;김희동;김동선;곽경민
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.218-219
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    • 2008
  • A gas-liquid centrifugal separator is widely used in industry because of its simple geometry and little maintenance. Also, these separators have considerable advantages over filters, scrubbers or precipitators in term of compact design, low pressure drop and higher capacity. A gas-liquid centrifugal separator is a device that utilizes centrifugal force and low pressure to separate liquid from gas by density difference. Design parameters such as length of separation space, swirl vane exit angle, inlet to outlet pipe diameter ratio, models for separation efficiency and low pressure drop as a function of physical dimension are not available in literature. In present study, length of separation space (from vane to gas exit opening) has been studied using CFD. The 3-D Navier-Stokes equations are numerically solved using a fully implicit finite volume scheme. Based upon the obtained solutions, tangential velocities, centrifugal forces, vortices and total pressure losses are analyzed to find the best design parameters.

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