• 제목/요약/키워드: contact stress analysis

검색결과 809건 처리시간 0.03초

자동차 헬리컬기어의 하중전달 특성해석 (Analysis of Load Transmission Characteristics for Automobile Helical Gear)

  • 박찬일;이장무
    • 한국자동차공학회논문집
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    • 제3권5호
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    • pp.1-9
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    • 1995
  • The purpose of this study is to develop a computer simulation program for analyzing load transmission characteristics of a helical gear system in design stage. In this analysis, the rotational delay, load distribution, root stress, and contact area are investigated. That is, the influence function of deflection is obtained by finite element analysis and the influence function of approach and gear tooth error are considered. Load distribution, rotational delay, and contact area are calculated by solving load-deflection equation which includes these influence functions and tooth error, and the influence function of the bending moment is obtained by finite element analysis. The root stress is calculated by the load distribution and the influence function of the bending moment. The results of the simulation are cross-checked through a specially designed experimental set-up.

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압축강도 평가를 위한 지능형 응력예측기 구축 (Construction of the Intelligence Stress Predictor for Compression Strength Evaluation)

  • 박원규;우영환;이종구;윤인식
    • 한국공작기계학회논문집
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    • 제10권6호
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    • pp.95-101
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    • 2001
  • This work is concerned with construction of the intelligence stress predictor far compression strength evaluation using neural network-ultrasonic waves. The contact pressure in jointed plates was measured by using ultrasonic technique. Neural network is used to evaluate and predict contact pressure from the results of the calibration curves. The organized neural system was leaned with the accuracy of 99%, as a result of learning the ultrasonic echo ratio to the contact pressure measurement between SM45C and STS410 materials. And it could be evaluated and predicted with the accuracy of 90% in the evaluation of ultrasonic echo ratio difference in the same surface roughness and contact pressure, and 85% in the prediction of virtual ultrasonic echo ratio. Thus the proposed stress predictor is very useful for the evaluation and prediction of the contact pressure between SM45C and STS410 materials.

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철도차량용 휠과 레일의 피로균열시작 수명에 관한 연구 (Study on the fatigue crack initiation life in rail wheel contact)

  • 김태완;설광조;조용주
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 추계학술대회 논문집(I)
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    • pp.733-738
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    • 2002
  • In this study, contact fatigue in wheel-rail contact is simulated. It is necessary to calculate contact stress and subsurface stresses accurately to predict fatigue behavior. Contact stresses are obtained by contact analysis of semi-infinite solid based on influence function and subsurface stress field obtained by using rectangular patch solutions. Based on these stress values, several multiaxial high-cycle fatigue criteria are used and the critical loads corresponding to fatigue limits are calculated. The simulation results show that the critical load is decreasing rapidly and the site of crack initiation also moves rapidly to the surface from the subsurface when friction coefficient exceeds a specific value for all of three fatigue criteria.

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슬루잉 링 베어링의 접촉응력분포에 관한 연구 (Analysis of Contact Stress in Slewing Ring Bearings)

  • 김청균;이승렬
    • Tribology and Lubricants
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    • 제11권2호
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    • pp.24-33
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    • 1995
  • This paper presents the contact stress distributions between the multi-contact bodies and the total reaction forces for various types of contact geometry for multi-load slewing ring bearings. The FEM results indicate that the slope of the roller type of slewing ring bearing has slightly steeper than that of the ball type. This is because the roller type wire race bearings is stiffer than the ball type bearing. The total reaction force of ball type slewing bearing shows much higher than that of wire race slewing bearings.

내연기관 밸브의 동적 접촉 및 응력 해석 (Analysis of Dynamic Contact and Stress of a Valve in Internal Combustion Engine)

  • 이기수;김동우;박상호;조성호;김방원
    • 한국자동차공학회논문집
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    • 제10권2호
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    • pp.159-165
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    • 2002
  • Numerical analysis of dynamic contact and stress developing in the high-speed driven valve of an internal combustion engine is presented. The valve is modeled by finite element techniques, and the dynamic contact between the valve and the valve seat is analyzed by the solution strategies of differential algebraic equations. Also an iterative scheme similar to the augmented Lagrange multiplier method is employed to enforce the contact constraints. It is shown that the contact and separation between the valve and the valve seat can be computed by the finite element techniques without assuming the artificial springs, and the efficiency and accuracy of the solution are demonstrated by the numerical examples.

연결고정, 인접면 접촉강도 및 치관길이에 따른 엔도포어 임플란트를 이용한 고정성 국소의치의 광탄성 응력 분석 (A PHOTOELASTIC STRESS ANALYSIS OF FIXED PARTIAL DENTURES WITH ENDOPOREIMPLANTS ACCORDING TO SPLINTING, CONTACT TIGHTNESS, AND CROWN LENGTH)

  • 정회열;최민호;김유리;조혜원
    • 대한치과보철학회지
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    • 제42권4호
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    • pp.425-442
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    • 2004
  • Statement of problem: A difficulty in achieving a passive-fitting prosthesis can be overcome by individual crown restoation of multiple implants. But individualized crown has another difficulty in control of contact tightness and stress distribution. Purpose: This in vitro study is to evaluate the stress distribution and the magnitude in the supporting tissues around Endopore implants with different crown lengths, interproximal contact tightness, and the splinting effects. Material & methods: Three Endopore implants($4.1{\times}9mm$) were placed in the mandibular posterior edentulous area distal to the canine and photoelastic model was made with PL-2 resin(Measurements Group, Raleigh, USA). Restorations were fabricated in two crown lengths: 9, 13 mm. For non-splinted restorations, individual crowns were fabricated on three custom-milled titanium abutments. After the units were cemented, 4 levels of interproximal contact tightness were evaluated: open, ideal($8{\mu}m$ shim stock drags without tearing), medium($40{\mu}m$), and heavy($80{\mu}m$). For splinted restorations, 3-unit fixed partial dentures were fabricated. This study was examined under simulated non-loaded and loaded conditions(6.8 kg). Photoelastic stress analysis was carried out to measure the fringe order around the implant supporting structure. Results: 1. When restorations were not splinted, the more interproximal contact tightness was increased among the three implants, the more stress was shown in the cervical region of each implant. When crown length was increased, stresses tended to increase in the apex of implants but there were little differences in stress fringes. 2. When nonsplinted restorations were loaded on the first or third implant, stresses were increased in the apex and cervical region of loaded implant. Regardless of interproximal contact tightness level, stresses were not distributed among the three implants. But with tighter interproximal contact, stresses were increased in the cervical region of loaded first or third implant. 3. When the nonsplinted restorations were not loaded, there were little stresses on the supporting structure of implants, but low level stresses were shown in the splinted restorations even after sectioning and soldering. 4. With splinted restorations, there were little differences in stresses between different crown lengths. When splinted restorations were loaded, stresses were increased slightly on the loaded implant, but relatively even stress distribution occurred among the three implants. Conclusions: Splinting the crowns of adjacent implants is recommended for Endopore implants under the overloading situation.

전 슬관절 치환 성형술에 사용되는 초고분자량 폴리에틸렌 삽입물의 접촉응력에 관한 유한요소해석 (Finite Element Analysis for the Contact Stress of Ultra-high Molecular Weight Polyethylene in Total Knee Arthroplasty)

  • 조철형;최재봉;최귀원;윤강섭;강승백
    • 대한의용생체공학회:의공학회지
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    • 제20권1호
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    • pp.37-44
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    • 1999
  • 인공 슬관절에 사용되는 초고분자량 폴리에틸렌(Ultra-high molecular weight polyethylene : UHMWPE)의 마모는 삽입물의 수명을 결정하는 주요 요인으로 작용한다. UHMWPE의 마모로 입자가 발생하여 조직반응을 일으키고 이에 따른 일련의 반응으로 골용해가 일어나 인공관절의 실패의 원인으로 작용한다. 여러 보고들에 의하면 관절 운동시 발생하는 접촉응력은 UHMWPE의 마모에 영향을 미치는 주요한 인자 중 하나로 알려져 있다. 그러나 이러한 보고들은 관절 접촉면에서의 접촉 조건만을 고려했고 UHMWPE 삽입물을 지지하고 있는 금속 지지판과의 접촉면에서의 접촉 조건은 고려하지 않았다. 본 연구에서는 이러한 접촉 조건들을 고려하여 UHMWPE의 모양, 두께, 마찰, 굴곡 정도 그리고 구성 요소들에 대한 UHMWPE 표면과 내부에서의 응력해석을 통해 이들 변수가 UHMWPE의 마모현상에 미치는 영향을 알아보았다. UHMWPE의 모양에 따른 관절의 일치정도(conformity)에 대한 영향의 경우, 일치정도가 높은 모델이 응력을 줄여줄 수 있는 유형으로 나타났으며, 금속 지지판과의 접촉면에서 접촉조건을 준 경우가 완전히 결합된 것으로 가정한 경우보다 UHMWPE 내부에서의 최대 응력이 1-2mm 더 아래에서 나타났다. 또한 UHMWPE로만 된 유형이 금속 지지판이 있는 유형보다 낮은 응력분포를 보여줌으로써 높은 응력으로 인한 UHMWPE의 마모와 균열을 줄이기 위해서는 UHMWPE로만 된 유형의 삽입물의 사용이 좋을 것으로 사료되었다.

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유한요소법을 이용한 Coating Layer의 접촉응력 해석에 관한 연구 (A Study on the Contact Stress Analysis of the Coating Layer Using Finite Element Method)

  • 김청균;오병택
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1996년도 제24회 추계학술대회
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    • pp.183-188
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    • 1996
  • Films and coatings are used for an enormous and diverse set of applications including mechanical, electronic and optical devices, protection at high temperature, cutting tools enhancement and automotive use. Many of these applications require the various properties associated with inorganic and metallic / non-metallic materials; i.e., with ceramics. Therefore, a large number of coatings have been developed and used for a long time in the various fields, especially in mechanical one. As one of the mutual surface actions, the problems of contact stresses are complex. The relationship between load and stress are nonlinear. Besides, the material is often apt to deform plastically under low load. However, analytical solutions exist only for some simple problems. If a material has a complicated shape or inhomogeneous properties, numerical method must be used. In this paper, the analysis of the contact stress of the coating layer was solved, using the finite element method.

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궤도형 전투차량의 궤도박리 발생 및 성장모드 예측에 관한 연구 (Separation Mode Analysis of Track Assembly of Main Battle Tank)

  • 이경호;박병훈
    • 한국군사과학기술학회지
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    • 제10권3호
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    • pp.173-180
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    • 2007
  • In this paper, we have proposed a simple finite element model for separation mode analysis on the roadwheel and track assembly of main battle tank and established a contact stress-based mechanism which could explain the initiation and growth of separation defect occurred during the test of padreplacable track. It was proved that the longitudinal contact shear stress component on the pin hole region of the track shoe body which is parallel to the driving direction is consistent with the crack initiation at the bonding surface between track shoe and wheel-side rubber. The longitudinal shear stress increased locally near the separated region after the separation initiated. So we could assume that the local stress concentration accelerates the separation growth according to the shear mode.

탄소/탄소 브레이크 디스크의 과도기 열탄성 해석과 3차원 응력해석 (Transient Thermoelastic Analysis and 3 Dimensional Stress Analysis of Carbon/Carbon Brake Disks)

  • 오세희;유재석;김천곤;홍창선;김광수
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2000년도 추계학술발표대회 논문집
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    • pp.147-152
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    • 2000
  • This paper presents the thermoelastic analysis and 3-D failure analysis of the carbon/carbon brake disk. The mechanical properties of the carbon/carbon brake disk were measured for both in-plane and out of plane directions. The mechanical properties were used as the input of the thermoelastic analysis and 3-D stress analysis for the brake disk. The gap between rotor clip and clip retainer was an important parameter in the loading transfer mechanism of the rotor. The change of gap was considered separating the mechanical deformation and thermal deformation. Because the rotor clip and clip retainers were not contacted, the clip retainers and rivets were excluded from the rotor analysis model. The disk was modeled by using the cyclic symmetry condition and the contact problem between the rotor disk and rotor clip was considered. From the results of the 3-D stress analysis, the stress concentration at the key hole of the brake disk was confirmed.

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