• Title/Summary/Keyword: Plate Fins

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Thermal Performance Analysis of a Shell-and-Tube Heat Exchanger with Plate Fins of Various Shape (다양한 형상의 판형 휜을 장착한 원통다관형 열교환기의 열성능 해석)

  • 신지영;손영석
    • Journal of Advanced Marine Engineering and Technology
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    • v.28 no.4
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    • pp.648-656
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    • 2004
  • In this study, a highly efficient shell-and-tube heat exchanger with plate fins is considered to improve thermal performance of the conventional shell-and-tube heat exchanger. This type of shell-and-tube heat exchanger with plate fins of various shape is simulated three-dimensionally using a commercial thermal-fluid analysis code. CFX4.4. The effect of the shape of the plate fin on heat transfer characteristics is also investigated by the simulation. Plate fins of four different shapes. plane, plane-slit. wave. and wave-slit fins, are considered. The flow fields, pressure drop and heat transfer characteristics in the heat exchanger are calculated. It is proved that the shell-and-tube heat exchanger with plate fins is superior to the conventional shell-and-tube heat exchanger without plate fins in terms of heat transfer. The shape of the plate fin is important in the performance of a heat exchanger such as heat transfer and pressure drop.

Natural Convection from a Vertical Flat Plate with Horizontal Rectangular Fins (수직평판(垂直平板)에 부착(附着)된 수평(水平)핀에서의 자연대류(自然對流))

  • Kim, S.J.;Lee, J.C.;Seo, L.S.;Kwon, S.S.
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.17 no.4
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    • pp.448-455
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    • 1988
  • A study has been conducted experimentally on natural convection heat transfer characteristics of a vertical flat plate with horizontal rectangular fins in air. The effects of fin heights and Rayleigh numbers are mainly investigated. The experimental results are as follows; 1. The mean fin, plate and total Nusselt numbers decrease as dimensionless fin heights H/S increase at $0.50{\leq}H/S{\leq}2.00$. 2. The mean fin surface Nusselt number in case of H/S = 0.50 and $Ra_c=4.33{\times}10^3$ shows its maximum at $X_1$, surface where there is no interference with other fins. 3. Owing to the interference of fins the mean plate Nusselt numbers at H/S=0.50 and 2.00 for $Ra_S=6.57{\times}10^3$ are 35% and 80% respectively less than the mean fin Nusselt numbers. 4. The mean fin, plate and total Nusselt numbers of horizontal rectangular fins show higher values at short fins, but lower values at long fins than those of upward vertical fins.

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Flow and Heat Transfer Characteristics of Aluminum Foam Porous Fins (발포알루미늄 다공핀의 열유동특성)

  • 김서영;백진욱;강병하
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.5
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    • pp.511-518
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    • 2000
  • The present experimental study investigates the impact of porous fins on the pressure drop and heat transfer characteristics in plate-fin heat exchangers. Systematic experiments have been carried out in a simplified model of a plate-porous fin heat exchanger at a controlled test environment. Comparison of performance between the porous fins and the conventional louvered fins has been made. The experimental results indicate that friction and heat transfer rate are significantly affected by permeability as well as porosity of the porous fin. The porous fins used in the present study show a similar air-side performance to the louvered fin. The correlations of friction and modified j-factor are also given for the design of the plate-porous fin heat exchanger.

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An experimental investigation of natural convection heat transfer from fin arrays on a horizontal flat plate (水平平板에 附着된 핀配列에서의 自然對流 熱傳達에 관한 實驗的 硏究)

  • 오원균;조진호;권순석
    • Journal of the korean Society of Automotive Engineers
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    • v.10 no.1
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    • pp.26-32
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    • 1988
  • A study has been conducted experimentally on the natural convection heat transfer characteristics of fin arrays on a horizontal flat plate in air. The effects of fin heights and Rayleigh numbers are mainly investigated. The experimental results are as follows; 1. The mean fin and mean total Nusselt numbers increase as dimensionless fin heights increase at 0.67.leg.H/s.leg.1.67. The mean plate Nusselt numbers increase in case of upward facing fins, but they decrease in case of downward facing fins. 2. The mean Nusselt numbers increase as Rayleigh numbers increase. 3. The mean fin surface Nusselt numbers has its maximum outside surface (Y$_{1}$) where there is no interference from each other fin. 4. The mean total Nusselt numbers in case of upward facing fins increase by 47% and 26%, respectively at H/S=0.67 and 1.67 than those in case of downward facing fins for Ra$_{s}$=6.50*10$^{3}$.>.

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Numerical Analysis of Fluid Flow and Heat Transfer in a Parallel-Plate Channel with Transverse Fins (수직휜이 부착된 평행평판 채널내의 유동 및 열전달에 관한 수치해석)

  • Hwang, K.Y.;Kim, H.J.;Moh, J.H.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.4
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    • pp.642-653
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    • 1995
  • An analysis is made of the laminar fluid flow and heat transfer characteristics in a parallel-plate channel to whose walls are fitted with a series of equidistant staggered fins placed transversely to the flow direction. The governing equations are solved numerically by a finite-volume method for elliptic flows. Based on the obtained solutions of flow and temperature fields, the effects of Reynolds number and various geometric parameters on the heat transfer performance and pressure drop are evaluated. A comparson of the heat transfer characteristics between the channels with and without staggered fins is also made.

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A Study on the Condensation Heat Transfer Characteristics of a Loop Heat Pipe Heat Exchanger for High Speed Rotary Shaft Cooling (고속 회전축 냉각용 루우프 히트파이프 열교환기의 응축열전달 특성에 관한 연구)

  • Cho, Dong-Hyun;Lee, Jong-Sun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.16 no.4
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    • pp.147-152
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    • 2017
  • In the present study, we used a loop thermosyphon heat exchanger consisting of condensers with internal fins and external plate fins which are 480 mm wide, 68 mm long, and 1,000 mm high. The heat transfer pipes in the heat exchanger were 15 mm in diameter and 1,000 mm in length, and 98 heat transfer pipes were installed in the heat exchanger. According to the experimental results, as the spaces between the internal discontinuous pins decreased, the frequency of pressure drops increased and changes in temperature at the outlet of the condenser were shown to be a little smaller. Therefore, we can see that as the spaces between internal discontinuous pins decreased, the heat transfer performance increased. For the loop heat pipe heat exchanger consisting of a condenser with internal and plate fins, as the temperature of the air flowing into the condenser increased, the condensation heat transfer rate also increased, and as the condenser refrigerant inflow temperature increased, the condensation heat transfer rate increased as well.

Application of CFD to tile Calculation of 2 Phase Cryogenic Heat Transfer Processes (2상 극저온 열전달 과정 계산에서의 CFD 응용)

  • Liu, Jie.;Yue, Haibo;Chung, Mo;Bai, Cheol-Ho
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.141-147
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    • 2011
  • A two-phase numerical model for plate-fin heat exchangers with plain fins and wave fins is studied incorporating the thermodynamic properties and the characteristics of fluid flow. The numerical simulations for the two fins in cryogenic conditions are earned out by employing a homogenous two-phase flow model with the CFD code ANSYS CFX. The heat transfer coefficients and the friction factor for nitrogen saturated vapor condensation process inside two types of plate fin heat exchanger are evaluated including the effects of saturation temperature (pressure), mass flow rate and inlet vapor quantity. The convective heat transfer coefficients and friction factors will be used for design of plate-fin type heat exchangers operating under cryogenic conditions.

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Cooling Performance of Thermoelectric Module with Air-Cooled Heat Exchanger Fins (공랭식 열교환핀이 부착된 열전모듈의 냉각 성능에 관한 연구)

  • Shin, Jae-Hoon;Han, Hun-Sik;Kim, Yun-Ho;Kim, Seo-Young;Hyun, Jae-Min
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.22 no.3
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    • pp.171-179
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    • 2010
  • Thermal performance of louver fin and plate fin in a thermoelectric cooling system with a duct-flow type fan arrangement is analytically evaluated. The thermoelectric cooling system consists of a thermoelectric module and two heat exchanger fins. The analytic results show that the optimized louver fin has lower thermal resistance than plate fin. The COP and heat absorbed rate of the thermoelectric cooling system with optimized louver fins are 10.3% and 5.8% higher than optimized plate fins, respectively.

Convective Heat Transfer Correlations for the Compact Heat Exchanger with Circular Tubes and Flat Tubes-Plate Fins (원형관 및 납작관-평판휜 형상의 밀집형 열교환기에 대한 대류열전달 상관관계식)

  • Moh, Jeong-Hah
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.3
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    • pp.291-299
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    • 2010
  • Aspect-ratio-based numerical analysis is carried out to investigate the air-side convective heat transfer characteristics in compact heat exchangers with circular tubes and flat tubes-plate fins. The RNG $k-{\varepsilon}$ model is adopted for turbulence analysis. The numerical analysis is carried out for aspect ratios ranging from 3.06 to 5.44 and for Reynolds numbers ranging from 1,000 to 10,000. The calculated results indicate a correlation between the friction factor and Colburn j factor in the compact heat exchanger system for the range of aspect ratios under consideration. The results obtained for circular tubes and flat tubes-plate fins in this study can be utilized to realize the optimal design of an air conditioning system.

Optimization for the Internal Structure of a Recuperator with Offset Strip Fins (오프셋 스트립 휜을 가지는 리큐퍼레이터의 내부 형상 최적화)

  • Do, Kyu-Hyung;Han, Yong-Shik;Choi, Byung-Il;Kim, Myung-Bae
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.6
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    • pp.1178-1185
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    • 2011
  • In the present study, a recuperator is suggested to improve the thermal efficiency of a micro gas turbine. Primary design parameters of the recuperator are determined from the ideal cycle analysis. The counter flow plate-fin heat exchanger with offset strip fins is chosen as the type of the recuperator. In order to satisfy the design constraints which are the minimum effectiveness and the maximum pressure drop, the optimization for the internal structure of the recuperator is performed with varying the fin spacing and the fin height of offset strip fins. Also the effects of the thermal conductivity of fins and separation plates and the longitudinal heat conduction on the thermal performance of the recuperator are investigated.