Development of a numerical analysis model using a flow network for a plate heat exchanger with consideration of the flow distribution

The performance of a plate heat exchanger (PHE) is severely influenced by non-uniform distribution of flow among its channels. Not only the PHEs, but many other process equipment needs uniform flow distribution for their optimum performance. Flow maldistribution (non-uniform distribution) is a common design problem which always puzzles process equipment designers. Being important design parameters, it has been investigated by several researchers and case based solution has been proposed and documented. Present numerical work is intended to target this aspect of the problem of PHEs but starts with a general investigation with simple multichannel geometry. The numerical setup consists of two headers having multiple channels for U-and Z-turn flow configuration under multichannel geometry and a simplified PHE for plate heat exchanger simulation. The problem has been investigated from hydrodynamic and thermodynamic view point. For hydrodynamic study, flow has been varied for Reynolds number 120 to 17600. It has been found that channel flow goes on reducing along downstream side. In thermal study the effect of wall temperature on air flow mal distribution has been investigated. Numerical results have been validated with the experimental results. Investigation reveals new features of flow mal-distribution which is helpful in better understanding of associated mal-distribution physics.

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Numerical Analysis with Experimental Validation of Single-Phase Fluid Flow in a Dimple Pattern Heat Exchanger Channel

Strojniški vestnik – Journal of Mechanical Engineering ◽

10.5545/sv-jme.2020.6776 ◽

2020 ◽

Vol 66 (9) ◽

pp. 544-553

Author(s):

Urban Močnik ◽

Bogdan Blagojevič ◽

Simon Muhič

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Numerical Analysis ◽

Single Phase ◽

Flow Characteristics ◽

Turbulence Models ◽

Plate Heat Exchanger ◽

Low Velocity ◽

Plate Heat ◽

Phase Water

A plate heat exchanger with a dimple pattern heat plate has a large number of dimples. The shape of dimples defines the characteristics of the plate heat exchanger. Although such heat exchangers have become increasingly popular due to their beneficial characteristics, knowledge of the flow characteristics in such kind of channel is poor. A good knowledge of the flow conditions inside of such channel is crucial for the successful and efficient development of new products. In this paper single-phase water flow in dimple pattern plate heat exchanger was investigated with application of computational fluid dynamics and laboratory experiments. Numerical analysis was performed with two turbulence models, Realizable - with enhanced wall treatment function and - SST. The first predicts a slightly smaller pressure drop and the second slightly larger compared to the results of laboratory measurements. Our research found that despite the relatively low velocity of the fluid, turbulent flow occurs in the channel due to its shape. We also found that there are two different flow regimes in the micro plate heat exchanger channel. The first regime is the regime that dominates the heat transfer, and the second is the regime where a recirculation zone appears behind the brazing point, which reduces the surface for heat transfer. The size of the second regime does not change significantly with the velocity of the fluid in the volume considered.

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Effect of flow distribution to the channels on the thermal performance of a plate heat exchanger

Chemical Engineering and Processing - Process Intensification ◽

10.1016/s0255-2701(01)00105-2 ◽

2002 ◽

Vol 41 (1) ◽

pp. 49-58 ◽

Cited By ~ 75

Author(s):

B. Prabhakara Rao ◽

P. Krishna Kumar ◽

Sarit K. Das

Keyword(s):

Heat Exchanger ◽

Thermal Performance ◽

Flow Distribution ◽

Plate Heat Exchanger ◽

Plate Heat

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Numerical Analysis of Composite Fouling in Corrugated Plate Heat Exchanger

Volume 4: Heat and Mass Transfer Under Extreme Conditions; Environmental Heat Transfer; Computational Heat Transfer; Visualization of Heat Transfer; Heat Transfer Education and Future Directions in Heat Transfer; Nuclear Energy ◽

10.1115/ht2013-17075 ◽

2013 ◽

Author(s):

Wei Li ◽

Hongxia Li

Keyword(s):

Heat Exchanger ◽

Numerical Analysis ◽

Heat Exchangers ◽

Fluid Velocity ◽

Plate Heat Exchanger ◽

Complex Flow ◽

Wall Functions ◽

Plate Heat ◽

Particulate Fouling ◽

Realistic Geometries

This paper provides a numerical analysis on precipitation and particulate fouling in a corrugated plate heat exchanger. This analysis started from the mass balance fouling model, and Realizable κ-ε model with non-equilibrium wall functions is used in the 3D numerical simulation considering the realistic geometries of the flow channel to obtained Nusselt number and wall shear stress, while Von-Karman analogy is used to obtain mass transfer coefficient. The numerical analysis is verified by experimental study. The predicted influence of fluid velocity in fouling resistance is compatible with experimental data that it can help to optimize the design of plate heat exchangers. The investigation significantly simplifies the fouling analysis of complex flow fields and can be used to assess the fouling potential of corrugated plate heat exchangers.

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A STUDY ON PERFORMANCE OF AIR-TO-AIR HEXAGONAL PLASTIC PLATE HEAT EXCHANGER

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132514500023 ◽

2014 ◽

Vol 22 (01) ◽

pp. 1450002 ◽

Cited By ~ 2

Author(s):

QING CUI ◽

MYUNG-DO OH

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Plate Heat Exchanger ◽

3D Analysis ◽

Plastic Plate ◽

Analysis Model ◽

Plate Heat ◽

Crest Length

In this research, 3D analysis model of air-to-air hexagonal plastic plate heat exchanger (HX) is developed numerically and compared with the available experiment. The heat transfer performances with polypropylene (PP) and aluminum (Al) indicate that PP HX can transfer heat as good as Al under this HX application. On the basis of this model, the crest length, the crest pitch and the inlet and outlet chamfer size are designed as three key parameters to improve the heat transfer performances of HX.

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