• Title/Summary/Keyword: 다관형

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NUMERICAL STUDY ON THE PERFORMANCE CHARACTERISTICS OF SHELL AND TUBE HEAT EXCHANGER BY FLOW DISTRIBUTORS : PART(II) HEAT TRANSFER CHARACTERISTICS (유동분배판에 의한 원통-다관형 열교환기의 성능 특성에 관한 수치해석적 연구(II): 전열특성)

  • Park, Y.M.;Lee, T.H.;Chung, H.T.;Kim, H.B.
    • Journal of computational fluids engineering
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    • v.21 no.4
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    • pp.28-32
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    • 2016
  • In the previous study, it is proved by numerical simulation that the baffle shaped as the porous plate installed in the inlet chambers improves the redistribution of the flow injecting to the tube bundles. In the present study, numerical simulation has been performed to investigate the effects of the flow distributors on the thermal characteristics of the shell and tube heat exchangers. The flow fields have been analysed by the three-dimensional Navier-Stokes solvers including the thermal conditions on the shell sides. The numerical results showed that the presence of the baffles improves the redistribution of the heat transfer to the tube bundles though the overall performance drop slightly on the present flow conditions.

A Study on Performance of the Circulating Gas-Solid Fluidized Bed Heat Exchanger with Multiple Vertical Tubes (다관형 가스-고체입자 순환유동층 열교환기의 성능 연구)

  • 박상일;최경빈;고창복;김정근
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 2002.05a
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    • pp.3-8
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    • 2002
  • 산업체에서 배출되는 여러 가지 배가스에는 부식성 오염물질을 함유한 경우가 많다. 따라서 이러한 배가스로 부터의 폐열회수를 위하여 부식성 오염물질에 의한 열교환기에서의 파울링의 문제점을 해결할 필요가 있다. 세라믹과 같은 고체입자는 대개 내식성이 강하므로 부식성의 배가스에 사용이 가능하고 유동층 열교환기에서는 고체입자의 비표면적이 매우 크므로 전열효율이 매우 높은 것이 특징이다.(중략)

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Study on Heat Transfer Characteristic of Shell-and-Tube Heat Exchanger with Plate Fin (판형 핀을 가진 원통-다관형 열교환기의 열전달 특성에 관한 연구)

  • Lim, Tae-Woo;Cho, Dong-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.1
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    • pp.46-51
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    • 2009
  • In this work, the experimental investigation was carried out to evaluate the heat transfer performance on the shell side of shell-and-plate finned tube heat exchanger with three different tube numbers(9, 13 and 19). Oil flowing on the shell side was cooled by cold water flowing inside the tubes. A shell-and-tube heat exchanger of an oil cooler consisted of one shell pass and two tube passes with the inner tube diameter of 8.82 mm and the tube length of 575 mm. Mass flow rate was varied from 1.2 to $6.0\;m^3/h$ for oil and from 0.6 to $3.0\;m^3/h$ for cold water, respectively. From the experiment of shell-and-plate finned tube heat exchanger, the overall heat transfer coefficient of heat exchanger with 9 tubes was compared with that of 13 and 19 tubes. It was found that the heat transfer coefficients in shell side of heat exchanger with 9 plate finned tubes showed averagely 1.8 times and 2.3 times higher than those of 13 and 19 tubes, respectively.

Inductive Inverse Kinematics Algorithm for the Natural Posture Control (자연스러운 자세 제어를 위한 귀납적 역운동학 알고리즘)

  • Lee, Bum-Ro;Chung, Chin-Hyun
    • Journal of KIISE:Computing Practices and Letters
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    • v.8 no.4
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    • pp.367-375
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    • 2002
  • Inverse kinematics is a very useful method for control]ing the posture of an articulated body. In most inverse kinematics processes, the major matter of concern is not the posture of an articulated body itself but the position and direction of the end effector. In some applications such as 3D character animations, however, it is more important to generate an overall natural posture for the character rather than place the end effector in the exact position. Indeed, when an animator wants to modify the posture of a human-like 3D character with many physical constraints, he has to undergo considerable trial-and-error to generate a realistic posture for the character. In this paper, the Inductive Inverse Kinematics(IIK) algorithm using a Uniform Posture Map(UPM) is proposed to control the posture of a human-like 3D character. The proposed algorithm quantizes human behaviors without distortion to generate a UPM, and then generates a natural posture by searching the UPM. If necessary, the resulting posture could be compensated with a traditional Cyclic Coordinate Descent (CCD). The proposed method could be applied to produce 3D-character animations based on the key frame method, 3D games and virtual reality.

Design of an 6 axial vertical multi-joint modular manipulator (6축 수직다관절 모듈형 매니퓰레이터 설계)

  • Ko, Young-Jun;Kim, Sang-Hoon
    • Proceedings of the Korea Information Processing Society Conference
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    • 2021.05a
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    • pp.525-528
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    • 2021
  • 본 논문은 산업현장이 아닌 카페등 생활현장에서의 폐기용 컵 처리를 목적으로, 사람을 대신해 지능적이고 기구학적으로 효율적인 다관절 메니퓰레이터의 설계 방법을 연구하였다. 다양한 장소에서 인간을 대신하여 임의의 위치에 있는 다양한 폐기 컵을 3D 카메라로 인식하여 알맞은 위치로 분리수거하는 6축 수직 다관절 모듈형 매니퓰레이터의 안정적인 동작을 위하여 기구부를 Yaw-Pitch-Pitch-Pitch-Yaw-Yaw의 6축 구조로 설계하고, 이를 구동하기 위한 관절 구동기의 용량을 분석하여 관절 구동기를 선정하며 전체적인 이해와 효율적인 분석을 위해 기구 전체의 외관을 3D 모델링 프로그램을 이용하여 구현하고 동작을 검증하였다.

Study on the Thermal Storage Characteristics of a Multi-capsule type LTES System -Analysis for Heat Charging and Discharging Process for Water Flow- (다관형 잠열축열장치의 축열특성연구 -물을 매체로 한 축열 및 방열과정 분석-)

  • Kim, Y.B.
    • Journal of Biosystems Engineering
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    • v.19 no.1
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    • pp.62-69
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    • 1994
  • This study was designed to seek information on the heat charging and discharging characteristics of a multi-capsule type LTES(Latent Heat of Fusion Thermal Energy Storage) system, and especially prediction equation of outlet water temperature from the system. During heat charging process, the water temperature in the LTES tank increased very slowly in comparison with a predicted one and was kept near the melting point of the PCM for about 25 minutes. During heat discharging process, the latent heat discharging period of the outlet water temperature became longer as the inlet water temperature became higher and/or mass flow rate became lower. The dimensionless temperature of the outlet water was predicted by linking three equations of ${\theta}=1.1Exp(-{\tau}/0.82)$, ${\theta}=-0.06{\tau}+0.3$, ${\theta}=0.8Exp(-{\tau}/1.4)$ ($r^2{\leq}0.88$) depending on discharging period regardless of mass flow rates on the case of the inlet water temperature at $21.5^{\circ}C$.

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