This study numerically investigates the influence of different vegetation types and layouts on microclimate air quality in residential districts based morphology green layout Nanjing, China. Simulations were performed using Computational Fluid Dynamics model ENVI-met. Four indices, i.e., cover ratio, grass shrub ecological landscaping plot ratio isolation index, combined to evaluate thermal wind fields, as well district models. Results show that under same (i.e., quantity all vegetation),...

The Air quality in student dormitories can have a major impact on the health of millions students China. This study aims to investigate ventilation and air dormitories. Questionnaire survey was conducted eight dormitory buildings field measurements were one during summer Nanjing. result reveals that most thought indoor outdoor neutral correlation between perceived is statistically significant. There are few PM2.5 ozone sources natural common form ventilation. However, there no significant...

Using computational fluid dynamic (CFD) simulations, the correlation between residential building arrangement designs and ventilation efficiency of various outdoor spaces is explored. Three indices—purging flow rate (PFR), visitation frequency (VF) air residence time (Tp)—are adopted to quantify regional spaces. these indices, changes in lateral spacing, length, stagger size were investigated under effects different surrounding arrays for wind directions. The simulation results indicated...

This research attempts to probe into the correlation between residential building layout and ventilation performance of various spaces in an operative level. To quantify influence design change on outdoor ventilation, numerical modeling technology is adopted with ANSYS-Fluent as simulation tool. As evaluate efficiency exterior space, local mean age air (L-MAA), which common used recent urban form studies, further discussed for region's neighborhoods. Using this index, several cases are...

Both outdoor and indoor ozone concentrations have negative health effects on human. This paper proposes an artificial neural network to estimate the a mass balance model tool concentrations. The prediction of concentration levels is great significance for people's health. estimation models are validated by measured data selected from monitoring stations field measurements in room Nanjing, respectively. accuracy evaluated. built this can generally some extent, while single zone useful...

To gain further insight into the ventilation at urban street intersections, this study conducted 3D simulations of right- and oblique-angled intersections under eight wind directions by using Reynolds-averaged Navier–Stokes (RANS) κ-ε turbulence model. The divergent responses pollution concentration for pedestrian zone (ped), near-wall (nwz), canopy layer to change in intersection typology direction were investigated. flow characteristics taken as air hub, explored employing indices such...

This paper discusses the influence of design variations on spatial distribution Ventilation Efficiency (VE) in idealized residential building groups. Series cases referring length and spacing changing are investigated using Computational Fluid Dynamics (CFD) simulation method. Air change rate (ACH) purging flow (PFR) adopted as evaluation indices ventilation efficiency. Simulation results indicate that these changes have evident effects Widening could improve efficiency different spaces....

The Covid-19 virus can spread rapidly in the air and cause epidemic to rage around world. This study takes a typical office as research object proposes four different partition settings suppress of based on displacement ventilation. And these strategies are verified by DPM model simulations two daily situations indexed person for coughing talking. then employed modified Wells-Riley evaluate effectiveness mitigating risk viral infection. As expected, absence partition, susceptible at other...

Respiratory diseases such as COVID-19 can be spread through airborne transmission, which is highly dependent on the airflow pattern of studied room. Indoor air typically not perfectly mixed even using a mixing ventilation, especially in large spaces. Airflow patterns open spaces hotel banquet rooms and plan offices, are particular concern, these usually accommodate more occupants thus have potential to rapidly leading outbreaks. Therefore, understanding help estimate detailed infection risk...

Abstract Buildings consume approximately 39% of the total energy used in US, which 53% is consumed by residential buildings. Besides, indoor air quality (IAQ) have significant impacts on occupant health since people spend average around 90% their time indoors. Nowadays, a great number green building technologies (GBTs) been developed and implemented buildings for reducing consumption improving IAQ. This paper proposes an approach to develop technology database including technology’s feature...