• 제목/요약/키워드: temperature characteristic

검색결과 2,914건 처리시간 0.027초

엔진 크랭크새프트 베어링의 마찰 및 온도 특성에 대한 실험적 연구 (An Experimental Study of the Friction and Temperature Characteristics of Engine Crankshaft Bearings)

  • 조명래;문호지;장인배;한동철
    • Tribology and Lubricants
    • /
    • 제11권1호
    • /
    • pp.44-49
    • /
    • 1995
  • Friction characteristic of an engine crankshaft bearing is affected by revolution speed, applied loads, and viscosity of lubrication. So, experimental investigation is required to observe the friction characteristics using these factors. Hydraulic cylinder, servo controller system which can be modified the applied load, and test rig for the observation of the characteristics of engine crankshaft bearings were designed and fabricated, and some experiments were performed. Friction torque, journal locus and circumferential temperature variation of crankshaft bearing were measured according to applied load, revolution speed, and oil inlet temperature.

분지 특성을 고려한 초전도 전류도입선 설계 (Design of Superconducting Current Leads Considering Bifurcation Characteristic)

  • 설승윤
    • 한국초전도ㆍ저온공학회논문지
    • /
    • 제1권2호
    • /
    • pp.37-42
    • /
    • 1999
  • The stability of high-temperature superconducting current leads for cryogenic devices are investigated. By assuming full transition from superconducting state to normal state at a transition temperature, the HTS current at a transition temperature, the HTS current lead shows bifurcation phenomenon. There is a bifurcation shape-factor, HTS leads have three steady state. Below the bifurcation shape-factor, the superconducting current lead is unconditionally stable, because there exists only one steady-factor HTS current lead is conditionally stable depending on the shape and intensity of disturbance.

  • PDF

Symmetric high voltage MOSFET의 extended source/drain 길이에 따른 전기적 특성의 고온영역 신뢰성 분석 (A study on the reliability test of Symmetric high voltage MOSFET under the extended source/drain length)

  • 임동주;최인철;노태문;구용서
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2003년도 통신소사이어티 추계학술대회논문집
    • /
    • pp.309-312
    • /
    • 2003
  • In this study, the electrical characteristic of Symmetric high voltage MOSFET (SHVMOSFET) for display driver IC were investigated. Measurement data are taken over range of temperature (300K-400K) and various extended drain length. In high temperature condition(>400K), drain current decreased over 20%, and specific on-resistance increased over 30% in comparison with room temperature.

  • PDF

고정밀 공작기계주축계의 열특성 해석에 관한 연구 (A Study on the Thermal Characteristics of a High Precision Machine Tool Spindle)

  • 김용길
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 1996년도 춘계학술대회 논문집
    • /
    • pp.47-51
    • /
    • 1996
  • Unsteady-state temperature distributions and thermal deformations of a spindle system are studied in this paper. Three dimensional model is built for analysis, and the amount of heat generation of bearing and the thermal characteristic values including heat transfer coefficient are estimated. Temperature distributions and thermal deformations of a model are analyzed using the finite element method and the termal boundary values. Numerical results are compared with the measured data. The results show that thermal deformations and temperature distributions of a high precision spindle system can be reasonably estimated using the three dimensional model and the finite element method.

  • PDF

Aerodynamic Optimal Design of Nozzle Contour for Supersonic Exit Mach Number

  • ;이창진
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2010년도 제34회 춘계학술대회논문집
    • /
    • pp.335-338
    • /
    • 2010
  • A recent study for tracing the profiles of supersonic axisymmetric Minimum Length Nozzle with uniform and parallel flow at the exit section, the stagnation temperature is taken into account. The aim of this work is to add optimization algorithm to the supersonic nozzle design in order to get the optimum nozzle shape. The comparisons of the nozzle contours based on the method of characteristics are presented. The specific heats and their ratio vary with the stagnation temperature when this temperature of a perfect gas increases. An application is made for air in a supersonic nozzle.

  • PDF

DC sputtering법을 이용한 Al/AlN/Si MIS capacitor 제작 및 수소첨가가 전기적 특성에 미치는 영향 (Effect of hydrogen addition to use DC sputtering method on the electrical properties of Al/AlN/Si MIS capacitor fabrication)

  • 김민석;권정열;김지균;이헌용;이환철
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 하계학술대회 논문집 D
    • /
    • pp.1919-1921
    • /
    • 1999
  • AlN thin films were fabricated by sputter for the application of MIS device with Al/AlN/Si structure. We controled that sub-temperature room-temperature. Sputtering pressure 5 mTorr, flow ratio Ar:$N_2$=1:1(4sccm:4sccm), and appended hydrogen gas $0{\sim}5%$. AlN thin films thickness fabricated to maintain $2700{\AA}$ time control. Before the experiment remove to the contaminated material use the Ultrasonic every 10 minute use the acetone and ethanol, then use the HF remove oxide-substance at 10 second. To analyze characteristic of the $H_2$ gas addition period, C-V and I-V characteristic make and experiment $H_2$ gas at addition period progressive capability of I-V and C-V characteristic.

  • PDF

최신 화상 재료의 소개 -마이크로 캡슐 토너- (Introduction of the Advanced Imaging Materials -Micro-encapsulating Treatment of Toner-)

  • 이용규;정경모;코세키 켄이치
    • 펄프종이기술
    • /
    • 제44권6호
    • /
    • pp.79-86
    • /
    • 2012
  • The aim of this general remarks is to introduce the results concerning the thermo physical, charging, developing and fusing characteristics of micro-encapsulated (MC) model toners in order to apply to the toner of electrophotographic system at the condition of a low temperature. In order to clarify the fusing mechanism of MC toner, rheological analysis of the toner was chosen. It was suggested that MC toner had a different fusing mechanism compared with non-MC toner. Some kinds of MC model toners showed a good result on adhesion test as well as cohesion test. Also, it was possible to get the good charging and development characteristic of MC toner for printing test with laser printer.

열재현에 의한 SS300 및 STS304의 기계적 성질 및 초음파 특성 (Mechanical Properties and Ultrasonic Characteristic of SS400 and STS304 by Simulated Heats)

  • 정정환;안석환;박인덕;남기우
    • 한국해양공학회:학술대회논문집
    • /
    • 한국해양공학회 2003년도 추계학술대회 논문집
    • /
    • pp.127-132
    • /
    • 2003
  • In a today industry, the welding is doing a many portion in structure manufacture. This study is simulated heat of heat-effected zone and researched a mechanical properties and ultrasonic characteristic in used the SS400 and the STS304. As the result mechanical properties of steel that become drawing decreased because of remaining stress by strain gardening according as simulated heat temperature rises, but according as temperature rises in material that do simulated heat after have done annealing, mechanical propensity was improved. The velocity and attenuation become different by effect of remaining stress than effect of material internal microstructure in ultrasonic wave test. In the case of STS304, there was change in mechanical properties by effect that is by strain hardening, but there was no change in material that simulated heat after annealing. When become drawing in ultrasonic waves test, according as simulated heat temperatures rise, change of attenuation coefficient is looked, but material that simulated heat after annealing was no change almost both the volocity and attenuation.

  • PDF

자동차 배기성능개선을 위한 확장형 공동파이프에 관한 연구 (A Study on the Expansion Cavity Pipe for Performance Improvement of Exhaust System in Automotive)

  • 손성만;박경석
    • 한국자동차공학회논문집
    • /
    • 제17권5호
    • /
    • pp.1-6
    • /
    • 2009
  • The temperature of exhaust gas was raised by increasing of engine movement on developing engine. Thermal of high temperature and pressure reverse in bellows, because of increasing of engine movement and the thermal performance of converter in combustion. As a result, thermal loss is increased and thermal efficiency is decreased rapidly in bellows, it can occur to damage in mechanical structure. In this study, it was necessary to analyze back pressure performance and thermal characteristic on driving condition in exhaust system. It was adapted braid type bellows and straight type exhaust pipe. It was compared with curve type exhaust pipe for lay-out on considering to design of exhaust system. It was necessary to improve thermal characteristic and back pressure performance so that expansion cavity pipe(ECP) was installed between bellows and catalyst convert. Not only decreasing back pressure was solved but also thermal characteristic problems in exhaust pipe because of increasing capacity. According to this study, the basis of data is presented when new exhaust system is designed.

촉매연소를 이용한 수소버너의 작동 특성에 관한 연구 (A Study about an Operating Characteristic of Hydrogen Burner by Using Catalytic Combustion)

  • 김태영;박창권;오병수
    • 한국수소및신에너지학회논문집
    • /
    • 제19권1호
    • /
    • pp.1-9
    • /
    • 2008
  • Human has faced in lack of fossil fuel and environmental crisis because of high population growth and development of industry. Hydrogen, unlimited amount and clean resource from water electrolysis, is remarkably known as the solution of recent energy crisis. One of the special characteristics of hydrogen is that a little amount of catalytic such as platinum and palladium makes nonflammable combustion, in other words catalyst combustion. Catalytic combustion fueled by hydrogen is environmentally friendly. This paper considers some comparisons of characteristic of catalytic combustion between a single layer of platinum catalyst, double layer of platinum and nickel catalysts and mixture of platinum and nickel catalysts. Some experiments of temperature distribution at different positions and characteristic of combustion in low temperature region were done in order to find an applicable possibility as a house-cooking burner.