Study on the thermal and hydraulic performance of fin-and-tube heat exchanger based on topology optimization

Thermal hydraulic performance of the fin-and-tube heat exchanger is presented in this paper. The purpose of this investigation was to investigate the heat transfer mechanism and flow characteristics in the finned tube heat exchanger with streamline tube. The streamline tube in this paper had the streamline cross section which was composed of a semicircle and a half diamond. Three-dimensional numerical simulation was presented and validated by the experiment and the other numerical simulation from public articles. The present simulation had good agreement with the experimental results. The difference of the j factor and f factor between the experimental results and present simulation results by k-ε-enhance model was less than 7.6%. The geometrical parameters were considered as every single variable to investigate the thermal hydraulic performance. The results showed that smaller transversal and larger tube pitch provided greater compactness and better thermal performance. Moreover, a larger angle was not only beneficial to enhance the thermal performance, but also helpful to improve the overall performance. Secondly, the effects of angle on the heat transfer performance and fluid flow characteristics were investigated as the perimeter kept constant. It was shown that the overall performance of the streamline tube was better than the circular tube. Lastly, the entropy generation including frictional entropy generation and the thermal entropy generation were analyzed. It can be concluded that by using the streamline tube, the wake region can be obviously reduced, and thermal performance can be improved.

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Impact of an Anisotropic Fin Surface Design on the Thermal-Hydraulic Performance of a Plain-Fin-and-Tube Heat Exchanger

Volume 10: Heat and Mass Transport Processes, Parts A and B ◽

10.1115/imece2011-63102 ◽

2011 ◽

Author(s):

Rong Yu ◽

Andrew D. Sommers ◽

Nicole C. Okamoto ◽

Koushik Upadhyayula

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Pressure Drop ◽

Heat Exchangers ◽

Hydraulic Performance ◽

Normal Operation ◽

Surface Design ◽

Tube Heat Exchanger ◽

Silane Coating ◽

Side Pressure

In this study, we have explored the effectiveness of heat exchangers constructed using anisotropic, micro-patterned aluminum fins to more completely drain the condensate that forms on the heat transfer surface during normal operation with the aim of improving the thermal-hydraulic performance of the heat exchanger. This study presents and critically evaluates the efficacy of full-scale heat exchangers constructed from these micro-grooved surfaces by measuring dry/wet air-side pressure drop and dry/wet air-side heat transfer data. The new fin surface design was shown to decrease the core pressure drop of the heat exchanger during wet operation from 9.3% to 52.7%. Furthermore, these prototype fin surfaces were shown to have a negligible effect on the heat transfer coefficient under both dry and wet conditions while at the same time reducing the wet airside pressure drop thereby decreasing fan power consumption. That is to say, this novel fin surface design has shown the ability, through improved condensate management, to enhance the thermal-hydraulic performance of plain-fin-and-tube heat exchangers used in air-conditioning applications. This paper also presents data pertaining to the durability of the alkyl silane coating.

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Comparison of Different Fin and Tube Compact Heat Exchanger with Longitudinal Vortex Generator in CFU-CFD Configurations

International Journal of Heat and Technology ◽

10.18280/ijht.390514 ◽

2021 ◽

Vol 39 (5) ◽

pp. 1523-1531

Author(s):

Katherine Barquín ◽

Alvaro Valencia

Keyword(s):

Heat Exchanger ◽

Vortex Generator ◽

Hydraulic Performance ◽

Vortex Generators ◽

Longitudinal Vortex ◽

Tube Heat Exchanger ◽

Tube Arrangement ◽

First Case ◽

Delta Winglet ◽

Oval Tube

Over the last decades several studies have searched for improved Fin and Tube Heat Exchanger (FTHE) designs capable of providing the best thermo-hydraulic performance. The present study aims at quantifying and comparing the thermo-hydraulic performance of different FTHE configurations. Six different designs were analyzed. The first FTHE consisted of an in-line circular tube arrangement and the last one was a FTHE with staggered oval tube with two pairs of Delta Winglet Vortex Generators (DWVG) in common flow up–common flow down (CFU-CFD) configuration. The best performance was obtained using DWVG in CFU-CFD orientation. This configuration enabled a 90% increase of the thermal performance factor when compared with the first case, using only two pairs of vortex generator´s per tube.

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Thermal-Hydraulic Performance and Optimization of Tube Ellipticity in a Plate Fin-And-Tube Heat Exchanger

Journal of Electronic Packaging ◽

10.1115/1.4043482 ◽

2019 ◽

Vol 141 (3) ◽

Author(s):

Hua Zhu ◽

Zhuo Yang ◽

Tariq Amin Khan ◽

Wei Li ◽

Zhijian Sun ◽

...

Keyword(s):

Heat Exchanger ◽

Pressure Drop ◽

Friction Factor ◽

Hydraulic Performance ◽

Pareto Optimal ◽

Maximum Heat ◽

Tube Heat Exchanger ◽

Simulation And Optimization ◽

Colburn Factor ◽

Overall Performance

The flow field inside the heat exchangers is associated with maximum heat transfer and minimum pressure drop. Designing a heat exchanger and employing various techniques to enhance its overall performance has been widely investigated and is still an active research. The application of elliptic tube is an effective alternative to circular tube which can reduce the pressure drop significantly. In this study, numerical simulation and optimization of variable tube ellipticity is studied. The three-dimensional numerical analysis and a multi-objective genetic algorithm (MOGA) with surrogate modeling are performed. Tubes in staggered arrangement in fin-and-tube heat exchanger are investigated for combination of various elliptic ratios and Reynolds numbers. Results show that increasing elliptic ratio increases the friction factor due to increased flow blocking area, however, the effect on the Colburn factor is not significant. Moreover, tube with lower elliptic ratio followed by higher elliptic ratio tube has better thermal-hydraulic performance. To achieve the best overall performance, the Pareto optimal strategy is adopted for which the computational fluid dynamics (CFD) results, artificial neural network (ANN), and MOGA are combined. The tubes elliptic ratio and Reynolds number are the design variables. The objective functions include Colburn factor (j) and friction factor (f). The CFD results are input into ANN model. Once the ANN is computed, it is then used to estimate the model responses as a function of inputs. The final trained ANN is used to drive the MOGA to obtain the Pareto optimal solution. The optimal values of these parameters are finally presented.

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