Optimizing Thermo-Hydraulic Performance in Heat Exchanger with Gradient and Multi-Layered Porous Foams

Abstract

In this study, the effect of gradient and multi-layered porous media is assessed for the optimized properties and arrangement in the tested novel baffle design arrangement, which results in further enhancement in its thermo-hydraulic performance. The computational study is carried out using ANSYS FLUENT; wherein the permeability and porosity for each layer is varied. It’s executed in two steps: case 1 – porous layers with variations implemented (constant, linear/stepwise, increasing/decreasing) and case 2 – porosity varied over the length. The findings show that the linear/stepwise increments in both cases give almost similar performance evaluation criteria (PEC) values. The increase in heat transfer rate and pressure drop can be compared using PEC, for better evaluation of the performance of different arrangements. With the simulation data genetic algorithm optimization model is used to find the optimal arrangement of the porous layers for both cases to maximize PEC further. The optimal arrangement for case 1 and case 2 taken individually, gives PEC of 2.425 and 2.401 respectively. And their simultaneous optimization gives highest PEC of 2.508. Additionally, to improve the heat transfer rate further, Al₂O₃ (5 w/v %) nanoparticles in water is tested with optimized conditions, which improves the PEC by almost double magnitude.

Additional information

Funding

This work is financially supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (No.51721004) and the 111 Project (B16038).

Notes on contributors

Syed Murawat Abbas Naqvi

Syed Murawat Abbas Naqvi is an Assistant Professor in NFC-IEFR, Faisalabad, Pakistan. He has done his Ph.D. from the Key Laboratory of Thermo-Fluid Science and Engineering, MOE, Xi’an Jiaotong University, China. His research interests are performance enhancement of heat exchangers, porous media, and numerical simulation.

Qiuwang Wang

Qiuwang Wang is a Professor of School of Energy & Power Engineering, Xi’an Jiaotong University, China. His research interests include heat transfer enhancement, high temperature/high-pressure heat transfer & fluid flow, transport phenomena in porous media, numerical simulation and prediction & optimization. He is the China Delegate of Assembly for Intl Heat Transfer Confs (AIHTC), a member of Scientific Council of Intl Center for Heat & Mass Transfer (ICHMT), a vice president of Chinese Society of Engineering Thermophysics in Heat & Mass Transfer, an Associate Editor of Heat Transfer Engineering, and Editorial Board Member for several international journals.

Muhammad Waqas

Muhammad Waqas is currently working at University of Sargodha, Sargodha, Pakistan. He has done his Ph.D. from CAS, China. His research interests are heat transfer enhancement, catalytic combustion for energy and environment applications, renewable energy, and CFD.

Ranjeetkumar Gupta

Ranjeetkumar Gupta is a Post-Doc. researcher at Heriot-Watt University, Edinburgh, UK. In his research he has specialized in the area of nanoparticles functionalization and polymer nanocomposites. He also specializes in CFD/FEA, modeling & simulation and works on design and performance optimization using Genetic Algorithm.

Faisal Rafique

Faisal Rafique is a Ph.D. student in the School of Mechanical Engineering, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University, China. His research interests are CFD, optimization, acoustics, and noise and vibration control of mechanical structures.