Influence of electrode arrangements on Electrohydrodynamics and transport phenomenon within water and porous samples connected to rectangular duct

A numerical study based on the concept of conjugate transport phenomena analysis has been developed for the investigation of heat transfer and fluid flow within a rectangular duct and a sample by Electrohydrodynamics technique. High electrical voltage and average velocity of inlet hot-airflow are applied at 20 kV and 0.1 m/s, respectively. Electrode arrangements or angle between electrode and ground are varied in a range of θ = 0-360°. The effect of swirling flow on EHD-enhanced heat transfer is also examined. The results show that electric field from various angles can induce the difference swirling flow pattern. By fluid flow within the sample is depended on the swirling flow and hot-airflow direction. Besides the shear flow effect, swirling flow is affected by temperature distribution. Therefore, it affects the sample. Furthermore, fluid flow from swirling flow effect and sample properties is the main mechanism of natural convection and conduction modes, respectively. Finally, the comparison of heat transfer enhancement between water sample and porous sample are also presented.