Air side pressure drop in plate finned tube heat exchangers

In shell and tube heat exchangers, the triple segmental baffle arrangement has been infrequently used, even though the potential of this baffle system for high thermal effectiveness with low pressure drop is generally known. This neglect seems to stem from the lack of published design guidelines on the subject. Lately, however, with the rapid growth in the size of nuclear heat exchangers, the need to develop unconventional baffling pattern has become increasingly important. A method to effectively utilize the triple segmental concept to develop economical designs is presented herein. The solution technique given in this paper is based on a flow model named “Piecewise Continuous Cosine Model.” The solution procedure easily lends itself to detailed analysis to determine safety against flow-induced vibrations.

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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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Influence of Circuitry Arrangement on the Pressure Drops of Two-Row Finned Tube Evaporators

Journal of Energy Resources Technology ◽

10.1115/1.1348271 ◽

2000 ◽

Vol 123 (1) ◽

pp. 100-103 ◽

Cited By ~ 1

Author(s):

Chi-Chuan Wang ◽

Min-Sheng Liu ◽

Jin-Sheng Leu

Keyword(s):

Pressure Drop ◽

Flow Pattern ◽

Cross Flow ◽

Finned Tube ◽

Parallel Flow ◽

Pressure Drops ◽

Heat Addition ◽

Side Pressure ◽

Flow Pattern Transition ◽

Flow Circuit

This study experimentally investigates the effect of circuitry on the refrigerant-side pressure drops of plate finned tube evaporators. Experiments were performed with countercross, parallel-cross, and z-shape arrangements. The results showed that the parallel-cross-flow circuit gives a lower pressure drop than other arrangements. Generally, the refrigerant-side pressure drops increase with air frontal velocities. However, for G=200 kg/m2s˙s and parallel flow, the pressure drops decrease with increase of air frontal velocity. This unusual characteristic is most likely related to the flow pattern transition when subjected to heat addition.

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Shell Side Pressure Drop of Shell-and-Tube Heat-Exchangers with Baffte Plates

Transactions of the Japan Society of Mechanical Engineers ◽

10.1299/kikai1938.31.419 ◽

1965 ◽

Vol 31 (223) ◽

pp. 419-426

Author(s):

Seikan ISHIGAI ◽

Eiichi NISHIKAWA ◽

Yoshiaki NAKAYAMA ◽

Shigeo TANAKA ◽

Ikuo SAIDA ◽

...

Keyword(s):

Pressure Drop ◽

Heat Exchangers ◽

Shell Side ◽

Side Pressure ◽

Shell And Tube

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Heat transfer and pressure drop characteristics of peripheral-finned tube heat exchangers

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2012.01.037 ◽

2012 ◽

Vol 55 (11-12) ◽

pp. 2835-2843 ◽

Cited By ~ 7

Author(s):

Bruno F. Pussoli ◽

Jader R. Barbosa ◽

Luciana W. da Silva ◽

Massoud Kaviany

Keyword(s):

Heat Transfer ◽

Pressure Drop ◽

Heat Exchangers ◽

Finned Tube

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Comparison of Additively Manufactured Louvered Plate-Fin Heat Exchangers

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4044348 ◽

2019 ◽

Vol 12 (1) ◽

Author(s):

Michael Bichnevicius ◽

David Saltzman ◽

Stephen Lynch

Keyword(s):

Heat Transfer ◽

Surface Roughness ◽

Pressure Drop ◽

Heat Transfer Rate ◽

Heat Exchangers ◽

Transfer Rate ◽

Print Quality ◽

Side Pressure ◽

Oil Cooler ◽

Fin Thickness

Abstract Additive manufacturing (AM) enables improved heat exchanger (HX) designs where performance is based on the achievable geometry. However, consequences of the AM process that affect HX performance such as increased surface roughness, dimensional tolerance issues, and defects like cracks may vary among identically designed AM parts due to AM machine settings. This paper experimentally compares the thermal and hydraulic performance of three AM HXs built using a traditionally manufactured, stamped aluminum oil cooler design. The AM HXs exhibited significantly higher air-side pressure drop and higher heat transfer rate than the traditional HX in large part due to increased AM surface roughness. Among AM HXs, one AM HX had notably higher heat transfer rate and air-side pressure drop due to poor print quality on the thin air-side fin features. The fin thickness among AM HXs also varied by about 15%, and there were only slight differences in surface roughness. This study indicates that functional HXs built using AM vary in performance even when the same digital model is used to print them and that AM HXs as a group can perform considerably differently than their traditional counterparts.

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FRTCOILS: A General Purpose Simulation Software for Design and Prediction of Thermal and Hydraulic Performance of Finned-Tube Compact Heat Exchangers

Volume 8: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A and B ◽

10.1115/imece2007-41409 ◽

2007 ◽

Author(s):

Maung Naing Naing Tun ◽

Nilufer Egrican

Keyword(s):

Heat Transfer ◽

Pressure Drop ◽

Heat Exchangers ◽

Water Solution ◽

Finned Tube ◽

Simulation Software ◽

Operating Conditions ◽

Object Oriented Programming ◽

Compact Heat Exchangers ◽

Cooling Coils

This paper presents computer software developed for rating and optimum selection of finned circular tubes compact heat exchangers with various coil geometries. The software is developed to use as a computing tool for commercial and R&D purposes in FRITERM A.S, an original equipment manufacturer (OEM) of finned tube heat exchangers. Finned-tube heat exchangers are highly utilized in refrigeration and process industries and heat transfer and pressure drop calculations are very important to manufactures and design engineers. For this purpose, a simulation and design software to predict the performance of finned-tube heat exchangers is presented. In finned-tube coils fin side fluid is air and tube side fluid can be water, oil, glycol water solution mixture and refrigerants. The analysis and rating of coils at dry and wet operating conditions are presented. Design and the most suitable selections of coils at the given parameters and design constraints from many different coil geometries are also performed in the software. User-friendly object-oriented programming C# is applied in developing the software. The software is developed in modular basic. Six modules are developed: Heating Coils, Cooling Coils, Condenser Coils, Steam Coils, Heat Recovery Coils and Evaporator (DX) Coils. REFPROP is also integrated in the software and all fluids’ thermal and transport properties are obtained from REFPROP. Heat transfer and pressure drop correlations available from literature are evaluated with recommendations. Simulated results are verified against experimental results.

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