• 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.

• 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.

• 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.

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.43-43
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• 2003

• 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.

• 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.

• 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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.1
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• pp.10-17
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• 1999

The present work presents condensation heat transfer and pressure drop data for the flow of R-12 in flat extruded aluminum tubes with small hydraulic diameters. The tube outside dimensions are $18mm(width){\times}1.7mm(height)$. Three types of internal geometry with the same outside dimensions are tested : sample 1 (7 tube holes), sample 2 (13 tube holes) and sample 3 (7 tube holes, micro-fin). The overall heat transfer coefficient is obtained for air-to-refrigerant heat transfer, and the Wilson plot method is used to determine the heat transfer coefficient for refrigerant flow. The sample 2 and sample 3 show significantly higher performance than sample 1. The heat transfer rates for the sample 2 and sample 3 are 9% and 12% higher, respectively, than sample 1. The friction factors for the sample 2 and sample 3 are 11.9% and 2.4% higher, respectively, than sample 1.

• Journal of the Korean Applied Science and Technology
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• v.37 no.1
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• pp.83-90
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• 2020

Plate heat exchangers(PHE) have been commercialized since the 1920s. Since then, although the basic concept of PHEs has changed little, its design and construction have progressed significantly to accommodate higher temperatures, higher pressures, and large heat exchanging capacities. The development trend of PHEs is consistent with heat plate developments with better thermal efficiency, lower pressure drop, and good flow distribution. The purpose of this paper is to introduce the main development processes of a plate cooler for medium-speed engine lubricant oil cooling in vessels which is in line with the development trend of PHEs and to provide its thermal performance data that were found out during experimental tests. The plate cooler in this study cannot measure the wall temperatures directly due to its structural characteristics, so the heat transfer coefficients were calculated using the modified Wilson Plot method. The water-to-water tests were first conducted experimentally to figure out the characteristics of heat transfer coefficients and pressure drops on the water side and then the water-to-oil tests followed to obtain the heat transfer coefficients on the oil side. The test results showed that heat transfer coefficients and pressure drops on both water and oil side increased with flow rates, and it was also found that all the development targets of the plate cooler in this study were achieved successfully.

• Journal of Power System Engineering
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• v.18 no.5
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• pp.22-27
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• 2014

The objectives of this paper are to obtain an empirical equations regarding the correlations between heat transfer and pressure drop of oval fin-tube heat exchanger having large diameter using wilson plot method. It was difficult to find any recommendable heat transfer and friction factor correlation available for our large diameter experimental cases. Overall heat transfer coefficients are composed of the heat transfer coefficients both inside and outside tubes. The resulting empirical correlations for the Nui and f-factor are given as $Nu_i=0.0146Re^{0.809}Pr^{0.3}$ and $f=4.366Re^{-0.64}$, respectively. The empirical correlations of the Nui and f-factors were developed for the large diameter oval finned-tube heat exchanger as a function of the Reynolds number. As the EG(Ethylene glycol) and air flow rate increases, the heat transfer rate and pressure drop is increased largely.