Numerical study on the effects of pollution source surface roughness on vortex ventilation performance, RoomVent 2024

¹ State Key Laboratory of Green Building, Xi’an University of Architecture and Technology, 710055, Xi’an, PR China
² School of Building Services Science and Engineering, Xi’an University of Architecture and Technology, 710055, Xi’an, PR China

^* Corresponding author: caozx@xauat.edu.cn

Abstract

To clarify the applicability of the complex pollution source for the vortex ventilation system and promote the practical application of vortex ventilation technology in the control of an industrial workshop environment, the influence of the surface roughness of pollution sources on the vortex ventilation system is analyzed in this study in terms of both the parameters of the vortex airflow field and the performance of the ventilation system by using reduced-scale experiment and numerical simulation methods. The results show that with the increase of the roughness density of the pollution source, the minimum pressure and maximum tangential velocity of the vortex decrease, while the magnitude of the maximum vertical velocity presents a trend of first increasing and then decreasing. Under the influence of roughness elements, the “vortex-dominated” particle transport characteristic of the vortex airflow is no longer significant, and the dispersion range and non-uniformity of the particles increase. When the roughness density λ<0.209, the enhancement of vertical airflow can shorten the capture time of particles. When designing a vortex ventilation system to capture pollutants generated by rough pollution sources, it is helpful to increase the lift angle of the supply airflow to improve the capture efficiency of particles.