10th International Aerosol Conference
September 2 - September 7, 2018
America's Center Convention Complex
St. Louis, Missouri, USA

Abstract View


Numerical Investigations on the Effectiveness of Urban-scale SALSCS under Idealized Atmospheric Conditions by Using a Large-eddy Simulation Model

QINGFENG CAO, Lian Shen, Sheng-Chieh Chen, David Y. H. Pui, University of Minnesota

     Abstract Number: 1428
     Working Group: Control and Mitigation

Abstract
In recent years, many urban regions have been experiencing severe air pollution, adversely affecting the health and living quality of city populations. A Solar-Assisted Large-Scale Cleaning System (SALSCS) was proposed as an innovative strategy aiming at utilizing buoyancy principle to generate airflow in large quantities with solar heating and facilitate the separation of fine particulate matter (PM) from atmospheric air for urban air pollution remediation. Previously, atmospheric simulations have been conducted over the terrain of Beijing in China by using the Weather Research and Forecasting (WRF) model, demonstrating that eight full-scale SALSCSs installed in the suburb of the city can reduce about 11 – 15% of the air pollution concentration in Beijing. In order to further improve the pollution cleaning efficiency of the system, an urban-scale SALSCS has been proposed recently, which has a solar collector and tower with dimensions of less than 120 m by definition, so that it can be directly installed inside city blocks to remove air pollutants and deliver clean air. In the current study, we performed atmospheric simulations by using a large-eddy simulation (LES) model, where large scale motions of a turbulent flow are computed directly and only small scale (sub-grid scale) motions are modelled. To evaluate the effectiveness of urban-scale SALSCS on combating air pollution, various idealized ambient conditions were considered, such as SALSCS operating in quiescent atmosphere or under different ambient wind speeds. Air pollutants and SALSCS airflow pattern have been implemented into the numerical model. The efficiency of urban-scale SALSCS in reducing air pollution concentration within a certain ambient range has been determined quantitatively based on the obtained numerical results. Flow patterns at the SALSCS surrounding regions were studied in detail, and interesting animations were created accordingly.