• 제목/요약/키워드: Instantaneous Temperature

검색결과 211건 처리시간 0.025초

가열조건에 따른 동부묵의 기호도 (Effect of Heating Conditions on Preference of Cowpea Mook)

  • 김성곤;이애랑
    • 한국식품영양과학회지
    • /
    • 제27권6호
    • /
    • pp.1100-1104
    • /
    • 1998
  • The preference test of cowpea mook(gel prepared with air-dried sediment of cowpea) indicated that the optimum concentration and heating temperature for mook-making were 8% at 95$^{\circ}C$ or 9% at 90$^{\circ}$and 95$^{\circ}C$ with continuous heating method(A), and 8% at 85$^{\circ}C$ or 7% at 9$0^{\circ}C$ with instantaneous heating method(B). Among the samples the mook made from 9% at 95$^{\circ}C$ with the method A was the most preferable. The degree of increase in hardness of mook prepared by the method B stored at 6$^{\circ}C$ for 8hr was much slower than that by the method A. the preference test of the mook stored at 6$^{\circ}C$ for 1 day revealed that the mook by the method A with 8%(95$^{\circ}C$) and by the method B with 7 and 8% (85$^{\circ}C$) were not significantly different.

  • PDF

사출 성형품의 금형내 잔류응력과 이형후 냉각에 의한 후변형 해석 (Deformation Analysis of Injection Molded Articles due to In-mold Residual Stress and Cooling after Ejection)

  • 양상식;권태헌
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 춘계학술대회논문집C
    • /
    • pp.251-256
    • /
    • 2001
  • Deformation analysis of injection molded articles whose geometry is considered as the assembly of the thin flat plates has been conducted. For the in-mold analysis, thermo-viscoelastic stress calculation of rheologically simple amorphous polymer and in-mold deformation calculation considering the in-plane mold constraint has been done. Free volume theory has been used for the non-equilibrium density state by the fast cooling. At ejection, the redistribution of stress together with instantaneous deformation has been considered. During out-of-mold cooling after ejection, thermoelastic model based on the effective temperature has been adopted for the calculation of deformation. Two typical mold geometries are used to test the numerical simulation.

  • PDF

원주의 근접후류에 대한 자유흐름 난류강도의 영향 (The effect of free stream turbulence on the near wake behind a circualr cylinder)

  • 김경천;정양범
    • 대한기계학회논문집
    • /
    • 제15권6호
    • /
    • pp.2062-2072
    • /
    • 1991
  • 본 연구에서는 역류의 측정과 원주의 근접 후류의 난류 구조에 미치는 자유흐 름 난류의 영향을 정성적 및 정량적으로 조사하기 위하여, 역류가 존재할 경우나 순간 유입각이 매우 큰 경우에도 난류의 측정이 가능한 split film probe(이하 SFP로 줄여 표기함)를 사용하여 평균 유동장과 난류의 2차 및 3차 모멘트의 변화, 속도 변동 상관 의 변화 및 대규모 와류의 유출 주파수 특성 등을 측정 분석하여, 격자에 의해 형성된 서로 다른 자유흐름 난류특성에 따른 실험 결과들을 비교 검토 해보고자 한다.

ANALYSIS OF DIRECT INJECTION SI STRATIFIED COMBUSTION IN HYDROGEN LEAN MIXTURE - COMBUSTION PROMOTION AND COOLING LOSS BY HYDROGEN -

  • Shudo, Toshio;Tsuga, Koichiro
    • International Journal of Automotive Technology
    • /
    • 제2권3호
    • /
    • pp.85-91
    • /
    • 2001
  • Characteristics of methane direct-injection spark-ignition stratified combustion in lean hydrogen mixture were analyzed both in a single cylinder engine and in a constant volume combustion chamber. Combustion pressure and Instantaneous combustion chamber wall temperature during the combustion process were measured with a thin-film thermocouple and used in analyses of combustion and cooling loss. Results in this research show that the premixed hydrogen increases cooling loss to combustion chamber wall while achieving combustion promotion, and the combustion system is effective especially in lean mixture conditions. Analysis of flame propagation was also done with Schlieren photography in the constant volume combustion chamber.

  • PDF

자동차 열부하의 계산 (A Study on the Heat Load Transferred to a Passenger Vehicle)

  • 오상한;이창원;원성필
    • 한국자동차공학회논문집
    • /
    • 제4권2호
    • /
    • pp.50-59
    • /
    • 1996
  • The computer simulation program that calculates the transient heat load transferred to a passenger vehicle has been developed. Method for modeling mathematically various kinds of the heat load was presented and the derived equations were solved numerically. To find out the accuracy of the simulation program, the correlation of experimental and analytical results was demonstrated. By using this program, the typical characteristics about temperature distribution and instantaneous or of vehicle body color, material of glass, air-conditioning capacity, driving direction, and speed. Under a steady-state condition, the ratios of the heat load, resulting form vehicle body, glass, and interior part, were 35%, 29%, and 36%, respectively.

  • PDF

Von-Kármán 회전 유동 하에서의 액체 실리콘의 응고와 열전달 (Heat Transfer and Solidification of Liquid Silicon in von-Kármán Swirling Flow)

  • 유주식
    • 대한기계학회논문집B
    • /
    • 제23권2호
    • /
    • pp.185-197
    • /
    • 1999
  • Heat transfer and solidification of liquid silicon in von-$K{\acute{a}}rm{\acute{a}}n$ swirling flow is investigated. The moving boundary is fixed for all times by a coordinate transformation, and finite difference method Is used to obtain the instantaneous location of the solid-liquid Interface and the heat transfer from the surfaces of solid and liquid. For small Stefan number or low wall temperature, the transient heat transfer from the surface of solid(QS(t)) is much larger than that from the liquid side of solid-liquid interface(QL(t)) and QL(t) reaches its quasi-steady-state value much faster than QS(t).

自然形 太陽熱暖房裝置 에 관한 硏究 (A Study on Natural Solar Heating System)

  • 박희용
    • 대한기계학회논문집
    • /
    • 제8권6호
    • /
    • pp.553-563
    • /
    • 1984
  • 본 연구에서는 선정한 난방모델에 대하여 열회로망을 만들어 각 구성성분에 대하여 에너지평형식을 세워 시뮬레이션 모델을 구하고 여기에 경계조건과 초기조건을 대입하여 수치해석으로 푼 결과를 실측치와 비교하였다. 또한 축열벽의 열용량변화, 통기구의 개폐, 통기구에 자동온도조절 홴(fan)의 설치, 야간단열의 설치 및 온실크기 의 변화 등이 온방온도에 미치는 영향을 규명하였다.

PIV/POD 기법을 이용한 냉장고 냉기류 성능평가 (Performance Tests of the Frozen Air Flows in a Refrigerator using PIV/POD Technique)

  • 김경천;김석로;김종욱
    • 한국가시화정보학회:학술대회논문집
    • /
    • 한국가시화정보학회 2007년도 추계학술대회
    • /
    • pp.97-100
    • /
    • 2007
  • A new evaluation method for the performance tests of the frozen air in a refrigerator using PIV(Particle Imaging Velocimetry) and POD(Proper Orthogonal Decomposition) techniques is introduced. A two-door refrigerator model was tested for the experiments. Actual temperature measurements were carried out for the drawer No.4 in refrigerator. By evaluating the characteristics of the interior flow of the refrigerator, an optimal shape of the drawer could be suggested through the PIV evaluation test. In this research, in order to find influences the turbulent kinetic energy contribution associated with the dynamic structures, we executed a POD analysis using the method of snapshots and the instantaneous fluctuating velocity field.

  • PDF

단순 급수관로에서의 워터 햄머 현상에 관한 연구 (The Experimental Study of Water Hammer by Valve Closure in Water Supply Piping System)

  • 이용화;유지오;박효석;김영호
    • 설비공학논문집
    • /
    • 제12권7호
    • /
    • pp.697-702
    • /
    • 2000
  • This study is to investigate the pressure wave characteristics and the maximum pressure rise generated by instantaneous valve closure at the end of the straightening copper piping system. Experiments were conducted under the following conditions : initial pressure 1~5 bar, flow velocity 0.6~3.0 m/s and water temperature $20^{\circ}C$ . Results indicated that the peak pressure generated by quick valve closure reached Joukowsky's value. And we also found that the maximum pressure rise and the pressure history were depended on not only closing time but also flow velocity.

  • PDF

열간압연중 발생하는 미세조직 변화에 관한 연구 (A Study On The Microstructural Evolution In Hot Rolling)

  • 조현중;김낙수
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 1995년도 추계학술대회논문집
    • /
    • pp.16-29
    • /
    • 1995
  • A full three-dimensional thermo-coupled rigid-viscoplastic finite element method and the currently developed microstructural evolution system which includes semi-empirical mathematical equations suggested by different research groups were used together to form an integrated system of process and microstructure simulation of hot rolling. The distribution and time history of thermomechanical variables such as temperature, strain, strain rate, and time during pass and between passes were obtained FEM analysis of multipass hot rolling processes. Then distribution of metallurgical variables were calculated successfully on the basis of instantaneous thermomechanical data. For the verification of this method the evolution of microstructure in plate rolling and shape rolling was simulated and their results were compared with the data available in literature. Consequently, this approach makes it passible to describe the realistic evolution of microstructure by avoiding the use of erroneous average value and can be used in CAE of multipass hot rolling.

  • PDF