• Title/Summary/Keyword: Plate finned tube

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Experimental Study on Heat Transfer Performance of Oil Cooler (오일 쿨러의 열전달 성능에 관한 실험적 연구)

  • Cho, Dong-Hyun;Lim, Tae-Woo
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2328-2333
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    • 2008
  • The experimental study 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 shell side heat transfer coefficient of heat exchanger with 9 tubes was compared with that of 13 and 19 tubes. It was found that the heat exchanger with 9 plate finned tubes showed more performance of heat transfer than that of 13 and 19 tubes.

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Heat Transfer Characteristics of Flat Plate Finned-Tube Heat Exchangers with a Variation of Fin Pitch and Number of Tube Row (핀-튜브 열교환기의 핀피치 및 열수 변화에 따른 열전달 성능특성에 관한 연구)

  • Kim Yong-Han;Lee Ho-Seong;Kim Yong-Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.10
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    • pp.930-937
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    • 2005
  • The objective of this study is to investigate the heat transfer performance of flat plate finned-tube heat exchangers with large fin pitch. In this study, twenty-two heat exchangers were tested with a variation of fin pitch, number of tube row, and tube alignment. The heat transfer coefficient decreased with a reduction of the fin pitch and an increase of the number of tube row. The staggered tube alignment improved heat transfer performance more than $10\%$ compared to the inline tube alignment. A heat transfer correlation was developed from the measured data for flat plate finned-tubes with large fin pitch. The correlation yielded good predictions of the measured data with mean deviations of $3.6\%\;and\;6.4\%$ for the inline and staggered tube alignment, respectively.

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.

Numerical Simulation of Plate Finned-Tubes Condenser (평판휜-관 응축기의 수치 시뮬레이션)

  • Min, M.S.;Choi, S.G.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.6 no.3
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    • pp.193-205
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    • 1994
  • A simulation program of the plate finned-tubes condenser widely used in the air conditioning system was developed. The program took into account the variations of the flow properties and fluid friction factor of refrigerant, and the heat transfer coefficients of refrigerant and air sides. The program was applied to a copper tube condenser which has outside diameter of 10.05mm, inside diameter of 9.35mm, length of 5.20m and three rows arraied staggered. Simulation results were such that refrigerant was super-heated state from the entrance to the 0.14m point, two-phase flow from the 0.14m point to the 4.10m point, sub-cooled state from the 4.10m point to the outlet. The degree of sub-cooled was $6.1^{\circ}C$. The variations of refrigerant quality, temperature, pressure, velocity, specific enthalpy, specific volume and air temperature, tube temperature were showed.

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A Study on Heat Transfer Enhancement of Oil Cooler (유냉각기의 열전달 촉진에 관한 연구)

  • Cho, D.H.;Lim, T.W.
    • Journal of Power System Engineering
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    • v.15 no.3
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    • pp.25-30
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    • 2011
  • A shell-and-tube oil cooler with plate fins was suggested to improve the defect of the conventional shell-and-tube oil cooler. Experiments were conducted to evaluate the heat transfer performance on the shell side of shell-and-plate finned tube oil cooler 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. From the experiment of shell-and-tube oil cooler, it was found that the heat transfer coefficient of oil cooler with 9 tubes, as oil flow rate was increased, was approximately 140% and 250% higher than that of 13 and 19 tubes, respectively. The heat transfer coefficient at the water flow rate of $3m^3/h$, also was 120% and 140% higher than that of 2.4 and $1.8m^3/h$, respectively.

Simulation of Coextrusion Process of Cladded Finned Tube by Plasticine (동시 압출법에 의한 핀형 튜브 Cladding 공정의 Plasticine 압출 모사)

  • Lee, Hyun-Woo;Park, Jin-Sung;Kim, Woo-Sik;Shin, Dong-Hyuk;Kim, Yong-Seog
    • Transactions of Materials Processing
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    • v.7 no.1
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    • pp.59-65
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    • 1998
  • In this study an attempt was made to simulate the coextrusion process of the cladded finned tube manufacturing by extrusion of plasticine. The effects of the billet and the plate inserted between the ingot and extrusion die on the variation of clad thickness of the extruded tube were studied. The results showed that cladded tube with uniform thickness can be obtained by a proper combination of clad thickness of billet and the plate. The relative strength of the billet and clad materials did not affect significantly on the variation of the clad thickness of the extruded tubes.

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A Study on the Characteristics of Plate Finned-Tubes Evaporator (평판핀이 부착된 증발기의 특성에 관한 연구)

  • 손병진;민묘식;김홍배
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.3
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    • pp.982-991
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    • 1991
  • 본 연구에서는 냉방기에서 널리 이용되고 있는 평판핀이 연속적으로 부착된 다관식 증발 열교환기에 대하여 (1) 냉매의 열역학적 물성치의 변화 (2) 냉매와 공기 측 열전달 계수의 변화 (3) 냉매측 관 마찰 손실등을 고려한 시뮬레이션 프로그램을 작성하고 그 결과를 실험을 통하여 보정 완성하였다. 계산결과로 부터 공조기기의 설계조건, 공조계통 해석을 위한 기초자료를 제시하였다.

Numerical investigation of plate fin performance for a compact heat exchanger (밀집형 열교환기에 사용하는 평판핀 성능에 관한 수치적 연구)

  • 유재욱;송태호
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.3
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    • pp.292-300
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    • 1999
  • Fin conduction not only enhances heat transfer to the ambient air but also increases tube-to-tube conduction. The latter is known to deteriorate the heat exchanger performance. Heat conduction between neighboring tubes thorough the fin is numerically investigated for accurate performance analysis of plate finned-tube heat exchangers. Governing equations for arbitrary plate fin are solved and the temperature distribution is obtained using the principle of superposition. Analysis is made using finite element method by changing the shapes of fin, the arrangements of tubes and the fin parameter mD. It is found that tube-to-tube conduction is significant when mD is small or the distance between neighboring tubes is small.

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Computation of Compact Heat Exchanger Performance by the Heat Exchangelet Method : Effect of Tube-to-tube Conduction along the Fin (미소열교환기법에 의한 밀집형 열교환기의 성능 계산 : 핀을 통한 튜브간 전도의 영향)

  • 성시경;송태호;최영철
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.5
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    • pp.494-501
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    • 2000
  • Effectiveness of a 3-pass plate finned-tube heat exchanger is calculated using heat exchangelet method by changing the shape of fin and the arrangement of tubes. The alternative refrigerant R134a is taken in this study. Conduction between neighboring tubes along the fin is taken into account in addition to convection between the fin and the surrounding air. Governing equations are obtained by using energy balance in a small control volume containing a tube and fins. They are numerically solved following the tube. Effect of tube-to-tube conduction is investigated in single-phase and two-phase flows with various fin shapes and arrangements of tubes. Improvement of effectiveness by fin perforation is studied too. The results shows that perforating fins, increasing the number of tubes, and increasing the distance between neighboring tubes at the same fin area enhance the effectiveness.

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Air-side Heat Transfer and Friction Characteristics of Finned Tube Beat Exchangers with Slit Fin or Plain Fin (슬릿과 평판 핀-관 열교환기의 공기측 열전달 및 마찰특성)

  • Kwon, Young-Chul;Chang, Keun-Sun;Park, Byung-Kwon;Kwon, Jeong-Tae;Jeong, Ji-Hwan
    • Journal of Energy Engineering
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    • v.16 no.1 s.49
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    • pp.7-14
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    • 2007
  • An experimental study is performed to investigate the effect of air-side heat transfer and friction on characteristics of finned tube heat exchanger under dry surface and wet surface conditions (RH 50%, 70%). Air enthalpy calorimeter is used to obtain the performance evaluation and analysis of a fined tube heat exchanger. Four finned tube heat exchangers with slit fin or plain fin are tested. The number of tube rows are 2 and 3, and the tube diameter is 7 mm. Air-side heat transfer and friction are presented in terms of j factor and friction factor. At dry surface condition, j factor decreases with increasing Re and j factor of 3 row is lower than that of 2 row. Also, the friction factor of a slit fin is larger than that of a plain fin. At wet surface condition, the heat transfer effect is more significant in the case of the slit fin than the plain fin and 2 row than 3 row. The j factor and friction factor are affected by humidity, tube row and fin configuration.