• Title/Summary/Keyword: Wilson plot

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Experimental Study on Heat Transfer Characteristics for Single-phase Flow in Plate & Shell Heat Exchangers by Using Wilson Plot Method (Wilson plot법을 이용한 Plate & Shell 열교환기의 단상유동 열전달 특성에 관한 실험적 연구)

  • Seo, M.K.;Kim, Y.S.;Lee, S.K.
    • Journal of Power System Engineering
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    • v.3 no.4
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    • pp.22-27
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    • 1999
  • Single phase heat transfer coefficients were measured for turbulent water flow in a plate & shell heat exchangers by using Wilson plot method. An experiment for counterflow heat exchange between the plate and shell was performed. The shell side heat transfer resistance was varied and the overall heat transfer coefficients were measured. The single-phase heat transfer coefficients in a plate side were obtained by Wilson plot method. Single-phase heat transfer correlations based on projected heat transfer area have been proposed for a plate & shell heat exchanger.

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Measurement of Heat Transfer Coefficient in a Flooded Evaporator through Wilson Plot Method (Wilson Plot을 이용한 만액식 증발기의 열전달계수 측정)

  • 윤필현;강용태;정진희
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.8
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    • pp.698-706
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    • 2004
  • Heat transfer coefficients of enhanced tubes in a flooded evaporator are measured through Wilson Plot method. And the correlations are proposed to design a flooded evaporators. Overall heat transfer coefficients are composed of the heat transfer coefficients both inside and outside tubes. Usually the experiments have been conducted separately. But there have been many difficulties like setting up the equipments and measuring the wall temperature. Wilson Plot method makes it possible to measure the separated transfer coefficients at the same equipment through experimental skills. So the cost and time can be reduced. And the results are reliable enough to use for design. Heat transfer coefficients inside the tube were able to be correlated uniquely in spite of various outside conditions. Boiling heat transfer of R134a is more dependent on the saturation temperature and much higher than that of R123.

Heat transfer coefficients for single-Phase flow in a micro-fin tube (마이크로휜 관내의 단상유동 열전달계수)

  • 권정태;김무환
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.4
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    • pp.423-430
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    • 1998
  • Single phase heat transfer coefficients were measured for turbulent water flow in a micro-fin tube by using Wilson plot technique. An experiment for counterflow heat exchange between the micro-fin tube and its outer annulus passage was performed. The annulus side heat transfer resistance was varied and the overall heat transfer coefficients were measured. The single-phase heat transfer coefficients in a micro-fin tube were obtained by Wilson plot technique. Nusselt numbers based on the real heat transfer area and the nominal area were about 35% and 50% larger than those for smooth tube respectively Also, single-phase heat transfer correlations based on real heat transfer area and nominal area have been proposed for a micro-fin tube.

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Experimental Study on Heat Transfer and Pressure Drop Characteristics for Single-Phase Flow in Plate and Shell Heat Exchangers. (Plate and Shell 열교환기의 단상유동 열전달 및 압력강하 특성에 관한 실험적 연구)

  • 서무교;김영수
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.4
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    • pp.422-429
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    • 2000
  • Plate and shell heat exchanger(P&SHE) is widely applied as evaporators or condensers in the refrigeration and air conditioning systems for their high efficiency and compactness. In order to set up the database for the design of the P&SHE, heat transfer and pressure drop characteristics for single phase flow of water in a plate & shell heat exchanger are experimentally investigated in this study. Single phase heat transfer coefficients were measured for turbulent water flow in a plate and shell heat exchangers by Wilson plot method. The shell side heat transfer resistance was varied and the overall heat transfer coefficients were measured. The single-phase heat transfer coefficients in a plate side were obtained by Wilson plot method. Single-phase heat transfer correlations based on projected heat transfer area and friction factor correlations have been proposed for single phase flow in a plate and shell heat exchanger.

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Experimental Study on Heat Transfer and Pressure Drop Characteristics for R-718 in Plate and Shell Heat Exchanger (Plate & Shell 열교환기내에서 R-718의 열전달 및 압력강하 특성에 관한 실험적 연구)

  • Kang, Seok-Hyun;Seo, Moo-Kyo;Kim, Young-Soo
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.270-275
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    • 2000
  • In this study, heat transfer and Pressure drop characteristics for R-718 in the plate and shell heat exchanger (P&SHE) investigated experimentally. The plates are circular and welded into a stack which fits into a cylindrical shell in P&SHE. Although apparently very different from rectangular the compact brazed plate heat exchanger (CBE), the underlying flow passage structure through the P&SHE is the same as in the CBE. The R-718 between plate side and shell side was performed a counterflow heat exchange. Heat transfer characteristic of R-718 were measured for turbulent flow in P&SHE by using wilson plot technique. Heat transfer experiment Ivas performed in the $200{\leq}Re{\leq}500$ regime and Pressure drop experiment was performed in the $150{\leq}Re{\leq}1600$ regime. The purpose of this study is to investigate heat transfer and friction factor correlations for R-718 in P&SHE and to offer fundamental data for experiment

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A study on the single-phase heat transfer in a counter-flow double-pipe heat exchanger by Wilson plot technique (Wilson plot기법을 이용한 2중관식 대향류 열교환기의 단상 열전달에 관한 연구)

  • Ohm, Ki-Chan
    • Journal of the Korean Solar Energy Society
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    • v.26 no.4
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    • pp.93-100
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    • 2006
  • An experimental study of a counterflow heat exchanger was performed. The heat exchanger had an effective heat transfer length of 1000mm and was operated in a counterflow arrangement with hot water($30{\pm}0.5^{\circ}C$, $Re_i=3500{\sim}20000$) in the inner tube(copper tube, $d_0=9.52mm$) and cold water($15{\pm}0.5^{\circ}C$, $Re_{DH}=10700{\sim}39000$) in the annulus(copper tube, $D_0=19.05mm$). Overall heat transfer coefficients were calculated and heat transfer coefficients in the inner tube and the annulus were determined using Wilson plots. The inner Nusselt number was compared with that of Gnielinski's correlation and they agreed within ${\pm}10%$ error. The trends were typical for a fluid-to-fluid heat exchanger with the overall heat transfer coefficient increasing with both inner and annulus flow rates. In the range of this experiment, Nusselt numbers for the inner tube flow were almost identical with those of the annulus flow at the same Reynolds number.

Heat Transfer Coefficients of Concentric Annuli for Testing Heat Transfer Characteristics of Alternative Refrigerants in Tubes (대체냉매 관내 열전달특성 시험을 위한 동심이중원관의 환상유로의 열전달계수)

  • KIM, MAN-HOE
    • Journal of Hydrogen and New Energy
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    • v.32 no.1
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    • pp.63-67
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    • 2021
  • Accurate measurements of the heat transfer coefficients of concentric annular space for the test section is important to measure the tube-side heat transfer coefficients of working fluids. This paper presents the annular side heat transfer coefficients of concentric annuli with variation of tube diameter ratios using Wilson plot method. The test facility has a straight, horizontal test section with an active length of 3.0 m. Inner/outer diameters of test tubes are 7.0/7.5 and 8.0/8.56 mm, respectively. An outer diameter of annulus side is 16.0 mm. The test results show that convective heat transfer coefficients in annuli increase with annular diameter ratio. The correlations for convective heat transfer coefficients in annuli are also developed.

Flow Boiling Heat Transfer Characteristics of R22 Alternative Refrigerants in a Horizontal Smooth Tube (R22 대체냉매의 수평원관내 흐름비등 열전달 특성)

  • 한재웅;김신종;정동수;김영일
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.4
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    • pp.242-251
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    • 2001
  • Flow boiling heat transfer coefficients (HTCs) of R22, R134a, R407C, and R410A were measured for a horizontal plain tube. The test section was made of a copper tube of 8.8mm inner diameter and 1000mm length respectively. The refrigerant was heated by passing hot water through an annulus surrounding the test section. All tests were performed at a fixed refrigerant saturation temperature of $5^{\circ}C$ with mass fluxes of 100~300 kg/$m^2$,/TEX>s. HTCs were measured by two methods: the direct wall temperature measurement method and the indirect Wilson plot method. Experimental results showed that the Wilson plot method was affected greatly by the external test conditions and yielded inconsistent results. For the mass flux of 100kg/$m^2$,/TEX>s, HTCs were almost constant regardless of the quality for a given refrigerant HTCs of R134a and R407C were similar to those of R22 while those of R410A were 60% higher than those of R22. For the mass fluxes of 200 and 300kg/$m^2$,/TEX>s, HTCs of R407C were almost the same as those of R22, while HTCs of R134a and R410A were 12-13% and 20~23% higher than those of R22 respectively. For pure refrigerant, Shah\`s correlation yielded a good agreement with the measured data both qualitatively and quantitatively.

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Performance Characteristics of Fin-Tube Heat Exchanger having Large Diameter Oval Tube for Dryer (대구경 타원관을 적용한 건조기용 핀-관 열교환기의 성능특성)

  • Bae, Kyung-Jin;Cha, Dong-An;Kwon, Oh-Kyung
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.1
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    • pp.8-13
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    • 2015
  • The objective of this paper is to provide design data of fin-tube heat exchanger which have a large diameter oval tube for dryer application. In this study, the heat transfer and pressure drop performance characteristics of the fin-tube heat exchanger were compared with Dittus-Boelter and a new correlation equation using Wilson plot method. The simulation results based on section by section method were compared with experimental results. These results showed that a new correlation equation using Wilson plot method provided better prediction, about 3 to 12%, than the Dittus-Boelter equation, from the experiment comparison. Also, the pressure drop of simulation results showed much more deviation with the experimental results.