Thermal–Hydraulic Performance Analysis of a Convergent Double Pipe Heat Exchanger

The present investigation proposes an innovative convergent double pipe heat exchanger (C-DPHE). A two-dimensional (2D) axisymmetric heat transfer model with counterflow is employed to analyze the thermal and hydraulic performance of this configuration numerically. The impact of convergence in the flow direction, using a wide range of contraction ratio (Cr), is explored. The effect of Reynolds and Prandtl numbers on the flow and heat transfer is addressed, as well. The model results were validated with available data from the literature, and an excellent agreement has been confirmed. In general, the findings of the present study indicate that increasing the contraction ratio increases heat transfer and pressure drop in the C-DPHE. Moreover, this configuration has a prominent and sustainable performance, compared to a conventional double pipe heat exchanger (DPHE), with an enhancement in heat transfer rate up to 32% and performance factor (PF) higher than one. Another appealing merit for the C-DPHE is that it is quite effective and functional at low Reynolds and high Prandtl numbers, respectively, since no high-operating pumping power is required. Further, the optimal operating conditions can be established utilizing the comprehensive information provided in this work.

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A Semi Empirical Methodology for Performance Estimation of a Double Pipe Finned Heat Exchanger

Volume 4: Fatigue and Fracture; Fluids Engineering; Heat Transfer; Mechatronics; Micro and Nano Technology; Optical Engineering; Robotics; Systems Engineering; Industrial Applications ◽

10.1115/esda2008-59124 ◽

2008 ◽

Author(s):

G. Arvind Rao ◽

Yeshyahou Levy

Keyword(s):

Heat Transfer ◽

Nusselt Number ◽

Heat Exchanger ◽

Heat Exchangers ◽

Operating Conditions ◽

Performance Estimation ◽

Wide Range ◽

Double Pipe ◽

Semi Empirical ◽

Pipe Heat

Finned tubes are one of the most widely used means of passively enhancing the heat transfer in circular tubes. Many investigators have proposed different correlations for predicting the performance of such heat exchangers based on their experimental investigations. However, the practical usage of such correlations is limited because of the variety of parameters that can influence Nusselt number and friction factor. Most of the correlations either have been developed with limited databases, or are geometry specific. Using CFD for analyzing performance of such heat exchangers is very computational intensive and hence cannot practically be applied for design optimization purposes. On the other hand, empirical correlations have many limitations in terms of their applicability. The objective of the present article is to present a physically based model for evaluating heat transfer and frictional loss for an internally and / or externally finned double pipe heat exchanger that can be applied in a wide range of operating conditions of practical importance. This paper describes a simple semi-empirical-numerical methodology to evaluate heat transfer and pressure drop characteristics in a finned tube heat exchanger with internal and/or external fins. Conduction and turbulent forced convection are the prominent modes of heat transfer. In order to resolve the operational characteristics of double pipe finned heat exchangers, a numerical methodology is presented which uses well known existing correlations for flow in a smooth pipe and flow over a flat plate. The method of successive substitution is used to solve the problem numerically. The proposed methodology is applied to some simple cases and the results compare well with existing data and correlations available in the literature. It is found that the addition of fins to such double pipe heat exchangers reduce the Nusselt Number; however the corresponding heat transfer rate is enhanced owing to the increase in the overall heat transfer area.

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3D Numerical Study of Conical and Fusiform Turbulators for Heat Transfer Improvement in a Double-Pipe Heat Exchanger

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2021.120995 ◽

2021 ◽

Vol 170 ◽

pp. 120995

Author(s):

Qingang Xiong ◽

Mohsen Izadi ◽

Mozafar Shokri rad ◽

S.A. Shehzad ◽

Hussein A. Mohammed

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Numerical Study ◽

Double Pipe ◽

Heat Transfer Improvement ◽

Pipe Heat

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Experimental study of heat transfer and friction factor in a double pipe heat exchanger using twisted tape with dimple inserts

Energy Sources Part A Recovery Utilization and Environmental Effects ◽

10.1080/15567036.2021.1927248 ◽

2021 ◽

pp. 1-30

Author(s):

Sanjay Kumar Singh ◽

Arvind Kumar

Keyword(s):

Heat Transfer ◽

Experimental Study ◽

Heat Exchanger ◽

Friction Factor ◽

Twisted Tape ◽

Double Pipe ◽

Pipe Heat

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Investigation of Overlapped Twisted Tapes Inserted in a Double-Pipe Heat Exchanger Using Two-Phase Nanofluid

Nanomaterials ◽

10.3390/nano10091656 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1656 ◽

Cited By ~ 1

Author(s):

Mehdi Ghalambaz ◽

Hossein Arasteh ◽

Ramin Mashayekhi ◽

Amir Keshmiri ◽

Pouyan Talebizadehsardari ◽

...

Keyword(s):

Heat Transfer ◽

Reynolds Number ◽

Performance Evaluation ◽

Heat Exchanger ◽

Evaluation Criterion ◽

Twisted Tape ◽

Performance Evaluation Criterion ◽

Twisted Tapes ◽

Double Pipe ◽

Pipe Heat

This study investigated the laminar convective heat transfer and fluid flow of Al2O3 nanofluid in a counter flow double-pipe heat exchanger equipped with overlapped twisted tape inserts in both inner and outer tubes. Two models of the same (co-swirling twisted tapes) and opposite (counter-swirling twisted tapes) angular directions for the stationary twisted tapes were considered. The computational fluid dynamic simulations were conducted through varying the design parameters, including the angular direction of twisted tape inserts, nanofluid volume concentration, and Reynolds number. It was found that inserting the overlapped twisted tapes in the heat exchanger significantly increases the thermal performance as well as the friction factor compared with the plain heat exchanger. The results indicate that models of co-swirling twisted tapes and counter-swirling twisted tapes increase the average Nusselt number by almost 35.2–66.2% and 42.1–68.7% over the Reynolds number ranging 250–1000, respectively. To assess the interplay between heat transfer enhancement and pressure loss penalty, the dimensionless number of performance evaluation criterion was calculated for all the captured configurations. Ultimately, the highest value of performance evaluation criterion is equal to 1.40 and 1.26 at inner and outer tubes at the Reynolds number of 1000 and the volume fraction of 3% in the case of counter-swirling twisted tapes model.

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A Conjugate Heat Transfer Analysis of a Triangular Finned Annulus Based on DG-FEM

Mathematical Problems in Engineering ◽

10.1155/2018/6947565 ◽

2018 ◽

Vol 2018 ◽

pp. 1-18

Author(s):

Muhammad Ishaq ◽

Khalid Saifullah Syed ◽

Zafar Iqbal ◽

Ahmad Hassan

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Conjugate Heat Transfer ◽

Strong Influence ◽

Heat Transfer Analysis ◽

Conductivity Ratio ◽

Geometric Configurations ◽

Specific Configuration ◽

Double Pipe ◽

Pipe Heat

A DG-FEM based numerical investigation has been performed to explore the influence of the various geometric configurations on the thermal performance of the conjugate heat transfer analysis in the triangular finned double pipe heat exchanger. The computed results dictate that Nusselt number in general rises with values of the conductivity ratio of solid and fluid, for the specific configuration parameters considered here. However, the performance of these parameters shows strong influence on the conductivity ratio. Consequently, these parameters must be selected in consideration of the thermal resistance, for better design of heat exchanger.

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