Numerical and Experimental Analysis of Heat Transfer Rate and Effectiveness of Gas-solid Cyclone Heat Exchanger

In this article heat transfer rate and effectiveness analysis were carried out on tangential inlet gas solid cyclone heat exchanger, numerically and experimentally varying with input parameters such as velocity of air (5 - 25 m/s), solid mass feeding (0.5 - 2.5 g/s) and particle size (300 - 500 µm) at a constant input air temperature of 473 K. Computational Fluid Dynamics (CFD) software, Ansys Fluent R21 were used to analyze swirl flow in cyclone heat exchanger using RSM turbulence model and particles were analyzed using Discrete Phase model (DPM). Results revealed that increasing the air velocity enhances the heat transmission from 42 W to 82 W and improves effectiveness from 0.64 to 0.88, attributed to increased turbulence and extended residence time for better heat exchange. Increasing solid feed rate raised heat transfer from 42 W to 196 W due to increased quantity of particles available for heat exchange; however, effectiveness slightly decreased from 0.64 to 0.56 due to reduced exit temperature and residence time. Larger particles led to decreased heat transfer rate (289 W to 251 W) and effectiveness (0.55 to 0.45), as they took a lesser number of turns inside the heat exchanger before exiting the cyclone, limiting heat transmission. The CFD simulation confirmed the cyclone heat exchanger design reliability and efficiency by demonstrating strong agreement with experimental data and aligned with literature, with a variance in heat transfer rate ranging from 10% to 19%, confirming the reliability and efficiency of the cyclone heat exchanger design. The effectiveness value of CFD is also well aligned with experimental results, with an R2 value of 0.976.