Buildings play a significant role in global energy consumption and carbon emissions, representing 40% of energy use and 36% of CO2 emissions. The indoor environmental quality (IEQ) within these structures is crucial for ensuring occupant health and comfort. However, achieving a healthy and comfortable indoor environment frequently results in increased energy demands. In response to this deficiency, this study builds a modular-based integrated platform called Green Design Studio (GDS) designed for the preliminary phases of multi-scale building design and urban planning. The GDS platform combines Rhino-Grasshopper and Computational Fluid Dynamics (CFD), embedded with various plugins and parallel computing to facilitate rapid assessments and visualizations of IEQ, outdoor air pollution, and energy efficiency. It adopts a modular strategy for analyzing building and urban components across different scales, including site analysis, space planning, occupancy patterns, building enclosures, and service systems. Measurement data derived from complex building scales are employed to calibrate the platform's effectiveness. This calibration is subsequently scaled up to urban extents and integrated with parallel computing to achieve rapid feedback. Such capabilities underscore the efficacy of the GDS platform, marking a significant advancement in high-performance building design tools that effectively combine ease of use with comprehensive and scalable performance analysis.

Alternative drag approaches for representing unresolved buildings were proposed in literature for computational fluid dynamics (CFD) simulation of macroscopic urban airflow. As a contribution, the present work derives the volumetric drag coefficient (C & lowast;d) through canopy drag and velocity analysis and provides appropriate correlations for C & lowast; d against urban morphological parameters. A total of 72 cases across various urban configurations are investigated, categorized by building typology, horizontal layout, height variability, and plan area density (7p, from 0.0625 to 0.57). Reynolds-Averaged Navier-Stokes (RANS) simulations with periodic boundary conditions are performed to model fully developed flows. Results for the normalized drag force and superficial velocity and their relations with 7p are evaluated. Subsequent evaluation of the profiles for the sectional coefficients (C & lowast;d(Z)) reveals four distinct types with variations in uniform-height cases and combinations in varying-height cases. A throughout correlations analysis, facilitated by data transformation, identifies the straightforward relations between C & lowast; d and frontal area density (7f) and tortuosity (z). The followed stepwise regression provides a recommended formula for C & lowast; d , demonstrating a proper fit with the simulated values. These findings facilitate the understanding and appropriate estimation of C & lowast; d and C & lowast; d ( Z ), promoting the application of macroscopic turbulence models, for neighborhood-scale wind and air quality studies.

Building materials are major sources of indoor volatile organic compounds (VOCs) and odors. This study investigated the emissions of VOCs and odors from emulsion paint and laminate flooring over a 264-hour period using a dynamic environmental chamber by gas chromatography-mass spectrometry/olfactometry (GC-MS/O) and sensory assessment methods. The odor intensity (OI) of emulsion paint and laminate flooring ranged from 1.4 to 3.5 and from 2.0 to 3.2, respectively, peaking at 12 h and stabilizing after 24 h. Both acceptability and hedonic tone exhibited a significantly negative correlation with OI. The total VOCs (TVOC) concentration of emulsion paint ranged from 626.7 to 1041.1 mu g/m3, while that in laminate flooring ranged from 43.4 to 581.2 mu g/m3. Based on odor activity values (OAV), toluene, ethylbenzene, styrene, 2-ethyl-1-hexanol, and decanal were identified as primary odorants emitted from the two building materials. The GC-MS/O method detected a great number of odorants, including 2-methyl-butane, cyclopentane, 2-ethyl-1-hexanol, nonanal, decanal, o-xylene and styrene in emulsion paint. Laminate flooring exhibited odorants with the first five being consistent with those found in emulsion paint and an additional two identified as benzene and toluene. Some disparity was noted between the primary odorants identified by the OAV and GC-MS/O methods. TVOC concentration and OAVsum showed no significant correlation with OI in the air mixture. These findings provide a preliminary investigation of the dynamic odor emission characteristics of building materials, highlighting the importance of comprehensive odor assessments.

The growing need for energy retrofitting in residential buildings aims to improve energy efficiency and occupant comfort, and address climate change. However, studies documenting retrofit implementation demonstrate that the actual energy performance and thermal comfort of retrofitted buildings deviate from predicted performance, underscoring the need for more comprehensive assessment methods. Moreover, occupant behavior plays a critical role in influencing building performance, often surpassing the effects of technical factors associated with building envelope and service products. Current assessment protocols fail to capture the complex, interconnected aspects of pre- and post-retrofitting conditions in occupied residential buildings. Therefore, this study presents an integrated protocol for monitoring multiple performance factors in pre- and post-retrofit assessments. This protocol was initially implemented for the pre-retrofit evaluation of two residential buildings in Syracuse, NY, using power meters and various indoor environmental and building envelope sensors. Motion sensors and door/window monitors tracked occupant behavior, supplemented by surveys on habits and indoor environmental quality. Findings highlight the significant impact of occupant behavior on energy consumption, thermal comfort, and IAQ. Challenges, lessons learned, and future considerations are discussed. This study underscores the need for occupant-centric retrofit strategies to optimize energy efficiency, enhance indoor environmental quality, and minimize occupant inconvenience.

Spatially-averaged wind profiles over the neighbourhood scale are commonly characterized in the literature as exhibiting exponential or logarithmic shapes. Further evaluation of in-canopy averaged velocity and its components-the main aim of this work-can contribute to a more comprehensive characterization of canopy wind conditions. The conventional computational fluid dynamics approach, modelling buildings by fully resolved method (FRM), is taken as the basis to evaluate the drag-based approaches: the porous media model (PMM) and the velocity reconstruction method (VRM). The VRM is particularly proposed as an engineering solution, implemented in Python, that uses drag-velocity functions to inversely calculate the averaged velocities in target neighbourhoods. Both fully-developed flows and flow adjustments through generic neighbourhoods within simplified districts under parallel and oblique inflows are investigated. The neighbourhoods feature moderate size, uniform height, regular and staggered arrangements, and varying plan area density (lambda p, from 0.07 to 0.40). Results reveal that the normalized volumetric drag coefficient (C & lowast;d) varies for the same neighbourhood under different flow conditions, e.g., with a median reduction of up to 20 % for regular-medium cases. The comparison demonstrates the PMM's ability to replicate wind profiles, despite with overestimation for windward neighbourhoods. The qualitative and statistical analyses (via R2 and RMSE) confirm that VRM predicts reasonable averaged velocity components, though it tends to slightly overestimate due to neglecting turbulence processes. Drag correlations, fitted in trigonometric Fourier series against wind direction, provide a lightweight program for estimating neighbourhood-averaged velocities, showing promise for integration into urban building energy modelling tools.

The SARS-CoV-2 virus caused the COVID-19 pandemic and brought major challenges to public health. It is transmitted via aerosols, droplets, and fomites. Among these, viral transmission through fomites is not well understood although it remains a very important transmission route. This motivated us to study how fomites play a role in viral transmission within controlled indoor environments. To achieve this, we investigated viral aerosol persistence on fomites under different humidity levels to mimic the built environment. We developed a protocol to study the effect of humidity on viral infectivity using a full-scale environmental chamber. The results show that the infectivity of aerosolized Phi6 in air decreased by ≥ 1 log10 as the relative humidity (RH) increased from 25% to 75% but then increased by ≥ 1 log10 as the RH further increased to 85%, resulting in a characteristic V-shape curve which varied with exposure time. Consistently, we show that although material properties may impact viral persistence, changes in the local humidity more significantly influence viral persistence on fomites. These results provide new insights into indoor fomite-mediated viral transmission under different environmental conditions. These findings will help guide the design of more effective strategies for viral control in indoor environments.

The office environment's indoor air quality (IAQ) and noise levels are critical factors that affect productivity and overall health. However, a research gap still exists on multi-domain impact of IAQ and noise on human physiological signals. The research aims to establish a comprehensive understanding of the multi-domain impact by analyzing physiological signals such as Electroencephalogram (EEG), Electrodermal Activity (EDA), eye blinks, jaw clenching, and heart rate. 30 human subjects participated in a series of tests in various indoor environments with portable air cleaner configurations. The study incorporated four scenarios with baseline condition and two noise levels. By comparing the different scenarios, the separate and combined impacts of IAQ and noise on office productivity were assessed. Meanwhile, physiological signals were collected and analyzed alongside productivity tests, which included typing and addition tasks, to determine the relationship between IAQ, noise, and office productivity. We discovered a strong relationship between EEG power and productivity, indicating that EEG power was a valuable indicator for evaluating indoor environmental quality, especially the multi-domain effects of IAQ and noise. When using the air cleaner, the relative power in the Theta, Alpha, and Beta bands indicated increased concentration and activity levels in the brain. Additionally, the increasing number of jaw clenching suggested that participants became more anxious and nervous in noisy environments. We also found that there were no gender differences for the analysis of EEG power, providing insights for future research. These findings have implications for smart control and built environment aimed at enhancing office workers' well-being and productivity.

Building surface cool materials are novel materials that can reduce urban heat island intensity and decrease building energy consumption. This study investigated the impact of radiative properties of materials, façade orientation, and morphological parameters on energy consumption in six typical residential neighborhoods in Nanjing, China. The neighborhood energy consumption of 16 application schemes considering the façade orientation factor is compared to determine the best energy-saving scheme. Seasonal and annual energy-saving rates, savings in electricity costs, and the price ceiling for materials per unit area are analyzed. The results show that for low-rise buildings, using cool materials only on the roof can reduce the annual energy consumption by 1%. When cool or super cool materials are also used on the building façade, the annual energy saving rate can be up to 3.4% and 4.3%, respectively. Using cool materials on the south façade of buildings is not recommended due to significant heat loss in winter. Considering savings in electricity costs and the price ceiling for materials per unit area, the price of cool and super cool materials should be less than 3.0 and 3.7 RMB/m 2 , respectively, assuming a lifespan of eight years in Nanjing.

Cool materials, with their high reflectivity, can significantly reduce the heat absorbed by buildings in summer and thus reduce energy consumption. The amount of solar radiation received by building surfaces varies with their orientation, so the effectiveness of cool materials on different building surfaces may vary. This study investigated the effects of using cool materials on scaled-down building models and full-scale real buildings through a combination of experiments and simulations, considering factors including building surfaces of different orientations, material properties, and weather conditions. Both experimental measurements and simulation studies showed that applying cool materials on roofs has the best cooling effect, reducing indoor temperatures by 0.93 degrees C in full-scale models. The south and west fa & ccedil;ades also showed good cooling effects when using cool materials. The north fa & ccedil;ade has the least cooling effect when using cool materials. Compared to exposed cement boards and regular materials, cool materials showed significantly better cooling effects, similar to those of 2 cm thick XPS insulation boards. Overall, buildings with poorer thermal insulation performance benefit more from the cooling effect of cool materials in summer. Additionally, the cooling effect of cool materials is ineffective on cloudy and rainy days. We found that the cooling effect of cool materials was significantly reduced when the solar radiation was less than 400 W/m(2). The findings of this study provide guidance for the use of cool materials in energy retrofitting of existing buildings and the construction of low-carbon cities.

Indoor environmental quality (IEQ) significantly impacts human health, well-being, and productivity. However, a comprehensive and in-depth review of the combined effects of IAQ and other multi-domain factors on human productivity is lacking. There has not been any prior review that encapsulates the impact of multi-domain factors on productivity and physiological responses of occupants. To address this gap, this review paper investigates and highlights the impact of IAQ and multi-domain factors (thermal, visual, and acoustic) on human productivity and occupant well-being in the built environment. The review explores various research methods, including evaluation of human productivity and creativity, data collection, and physiological signal analysis. We also examined the interactions between IAQ and multi-domain factors, as well as strategies for optimizing productivity through integrated building design and smart systems. The key findings from this review reveal that IAQ significantly impacts human productivity and occupant well-being, with interactions between IAQ and other IEQ factors further impacting these effects. Despite advances in the field, there are several limitations and gaps in the current research methods and study designs, including small sample sizes, limited and insufficient experimental design and control, reliance on laboratory or simulated environments, lack of follow-up and long-term data, and lack of robust performance metrics. The review proposes future research directions, including specific applications, and follow-up work to address these limitations and further advance the understanding of IAQ and multi-domain factors in the built environment. The implications of this review for policy and practice include the need for holistic and integrated approaches to IAQ and IEQ management, with a focus on creating healthy and productive indoor environments. This review emphasizes the importance of considering the complex interplay between IAQ and multi-domain factors, as well as the potentials of adopting smart control systems and sustainable design strategies to optimize productivity and occupant well-being in the built environment. By addressing these critical issues, we can enhance the overall quality of life for building occupants and contribute to a more sustainable future.

Thorough investigations of urban-canopy drag primarily stemming from pressure drag on building surfaces are necessary given the turbulent flows within complex urban areas. Moreover, a gap persists regarding the relationships between canopy drag and breathability. Therefore, this work delves into the canopy-layer airflow dynamics for generic urban neighborhoods by performing three-dimensional Reynolds-Averaged Navier-Stokes simulations. A total of 32 subcases are examined, encompassing uniform- and varying-height and diverse plan area densities (λp, categorized into groups of sparse: 0.0625/0.067, medium: 0.23/0.25, and dense: 0.53/0.56). Results for the drag distribution highlight the windward-row shelter effect for the medium and the dense, local shelter by taller buildings, and distinct shapes of sectional drag forces (F* Z). Local velocity and mean age of air are found strongly positively and negatively correlated to F* Z, respectively, with distinct slopes in relation to λp. For the uniform-height, the normalized bulk drag (F* bulk, referred to as drag coefficient in literature) peaks for the medium with wake-interference regime; F* bulk demonstrates a maximum increase of over two times with height variation; moreover, F* bulk for varying-height groups exhibits a marked increase from the sparse to the medium, while remaining comparable values for the dense. The frontal area averaged drag (FAf,ave) exhibits a decreasing trend against λp across all cases. Further, FAf,ave exhibits strong correlations with λp and porosity, and with bulk ventilation indices such as spatially averaged velocity, air change rate, and normalized net escape velocity. Throughout the ‘suburban-urban-suburban’ canopy, medium neighborhoods exerting larger drag cause greater streamwise outdoor pressure drops and flow reductions compared to the sparse. However, dense neighborhoods with lower drag exhibit even larger pressure losses, which should be carefully scrutinized. The findings can inform urban planners in designing more aerodynamically efficient neighborhoods and guide strategies for improving air quality within urban environments.

Cool materials for building surfaces have been invented to reduce building energy consumption. This study aimed to investigate the impact of cool and super cool materials on the energy consumption of residential neighbourhoods in Nanjing. First, the impact of microclimate on building energy consumption simulation is investigated. An energy correction model is obtained to consider the impact of microclimate factors when energy consumption is calculated using meteorological data. Compared to meteorological data, the wind speed in the microclimate data for the urban centre is significantly lower, and the temperature is significantly higher. In addition, the seasonal and annual energy saving rates of cool and super cool materials in six typical residential neighbourhoods are analyzed. The results show that cool and super cool materials are very effective for reducing building energy consumption in summer, with energy saving rates of up to 13.85 % for cool materials and 17.74 % for super cool materials. However, building energy consumption increases in winter when using cool and super materials, so it is necessary to evaluate the energy saving effect of cool materials based on annual energy consumption. Overall, for residential neighbourhoods in Nanjing with a sky view factor less than 0.45, the annual energy saving rate is 1.95 % for cool materials and 2.35 % for super cool materials. The conclusions of this study can provide a guide for energy conservation policy in residential neighbourhoods in Nanjing.

Relevant drag measurements in wind tunnels contributed to the drag parametrization. This reduced-scale numerical work further examines drag distribution and the relation between drag force and outdoor ventilation efficiency. Neighbourhood-like block arrays with planar area densities (lambda p) from 0.0625 to 0.25 and five distinct form types are investigated, extending a prior drag experiment solely on cube regular arrays. The approaching flow reshaped by these arrays exhibits flow adjustment and drag evolution. Drag distribution analysis demonstrates varied shelter effects and different shapes of sectional drag profiles. Arrays featuring larger lambda p and staggered layout generally exhibit higher normalized bulk drag force (F*bulk), but lower normalized frontal area-averaged drag (F*Af ,ave). Further, F*bulk and F*Af ,ave demonstrate strong negative correlations with normalized spatially averaged velocity, showing the potential to reflect the ventilation efficiency within neighbourhoods. Drag area density and drag-to-frontal area ratio are assessed as alternatives to interpret the drag, and it reveals half of the physical frontal area for medium arrays can serve as approximately estimated drag area. It is noted that the qualitative evaluation provides insights into the drag distribution and drag interpretation, while the quantitative correlation is limited to the examined morphological scenarios.

Four building arrays, each comprising 25 building models, were utilized to investigate the effects of cool materials on building surface temperatures, indoor temperatures, and street microclimates in Guangzhou, China. The experiments are divided into three groups. The first group of the experimental models is used to investigate the cooling effect of the roof using cool materials on the roof surface and indoor environment. The results show that using cool materials on roofs can significantly reduce roof surface and indoor temperatures of the top floor by 13.5 degrees C and 3.9 degrees C at noon under an average global solar radiation (GSR) of 727 W/m2. The second group of experiments included four arrays: one control group without cool materials and three other arrays applying cool materials on the third, second, and first floors, respectively. Using cool materials on the fa & ccedil;ades of the third, second, and first floors reduced the indoor temperature by an average of 1.9 degrees C, 0.8 degrees C, and 0.5 degrees C (average GSR = 404 W/m2), respectively. As a result, higher floors receive more solar radiation, and cool materials show better cooling capacity. The third group is used to investigate the effect on street air temperatures when cool materials are used on all building fa & ccedil;ades. Overall, the effect of cool materials on the street air temperature is very small, with a maximum reduction of only 0.2 degrees C in the street air temperature.

This study is specifically aimed at evaluating commercially available metal oxide (MOx) sensors for real-time monitoring of volatile organic compounds (VOCs) in typical indoor environments. To evaluate MOx sensors' performance, we used a 50 L environmental chamber system to provide a well-controlled testing environment. The VOC types and test concentrations were based on relevant indoor air quality (IAQ) standards and guides in the literature. Test VOCs included toluene, formaldehyde, m-Xylene, phenol, benzene, naphthalene, acetaldehyde, acetone, dichloromethane, tetrachloroethylene, 1,1,1-trichloroethane. The evaluation tests are categorized into individual VOC tests, mixture VOCs tests, temperature and relative humidity dependence tests, short-term stability tests, and long-term drifting tests to investigate the sensitivity to specific VOC, mixture coinfluence under realistic condition, moisture compensation, and reliability. This paper focuses on the procedures and results of the toluene test, identifying necessary improvements in the algorithm through comparisons between rawsignals and TVOC readings. Results of this study will help provide guidance on the selection and utilization of MOx VOC sensors for VOC monitoring and IAQ control.

The Covid-19 virus can spread rapidly in the air and cause the epidemic to rage around the world. This study takes a typical office as the research object and proposes four different partition settings to suppress the spread of the virus in the air based on displacement ventilation. And these strategies are verified by DPM model simulations of two daily situations of indexed person for coughing and talking. This study then employed a modified Wells-Riley model to evaluate the effectiveness of these strategies in mitigating the risk of viral infection. As expected, in the absence of a partition, a susceptible person at the other end of the seat greatly increased the risk of infection. Partitions can significantly reduce the risk of infection (100% → 20%), while partitions with a full-wrapped structure can reduce the risk of infection to less than 1%. For the instantaneous release scenario of coughing, the barrier can capture a large particle diameter (>50 μm) particles, and the smaller particle diameter can be discharged out of the room with the thermal plume. The strategies provided in this study can provide recommendations for indoor epidemic prevention and control in the context of the Covid-19 pandemic.

New York State (NYS) has over 750,000 dwelling units with inefficient HVAC and domestic hot water (DHW) supply. To explore the opportunities of carbon neutrality, in this paper, we investigated and evaluated an integrated HVAC and domestic hot water system that could meet all the heating, cooling, ventilation, dehumidification, DHW and air cleaning requirements for a single dwelling unit. To evaluate its feasibility in the U.S., lab testing was conducted at first. It focused on the air side to evaluate the system capacities in an environmental chamber that could mimic different outdoor conditions in lab space. Then, a nation-wide EnergyPlus simulation was conducted in seven different climate zones. Lastly, a nation-wide energy simulation using MPC was also conducted. Compared to the results of EnergyPlus, it showed around 60

Air-side economizers are increasingly used to take advantage of"free-cooling"in data centers with the intent of reducing the carbon footprint of buildings.However,they can introduce outdoor pollutants to indoor environment of data centers and cause corrosion damage to the information technology equipment.To evaluate the reliability of information technology equipment under various thermal and air-pollution conditions,a mechanistic model based on multi-ion transport and chemical reactions was developed.The model was used to predict Cu corrosion caused by Cl2-containing pollutant mixtures.It also accounted for the effects of temperature(25 ℃ and 28 ℃),relative humidity(50％,75％,and 95％),and synergism.It also identified higher air temperature as a corrosion barrier and higher relative humidity as a corrosion accelerator,which agreed well with the experimental results.The average root mean square error of the prediction was 13.7 Å.The model can be used to evaluate the thermal guideline for data centers design and operation when Cl2 is present based on pre-established acceptable risk of corrosion in data centers'environment.

Three-dimensional computational fluid dynamics (CFD) simulations based on the discrete phase model were performed to explore the spatial distribution of traffic-related PM2.5 in summer and winter in nine typical neighborhoods (300 x 300 m) established through investigating realistic samples in Nanjing, China. These cases have different building typologies, building heights, and neighborhood layouts. The focus was on the pollutant dispersion along horizontal and vertical directions and the average near-facade (0.5 m away) concentration of different floors. The harm to residents' health caused by excessive concentration (>25 mu g/m3) was quantified by decrease in life expectancy (DLE). Results show the pollutant dispersion distance along the horizontal direction was limited, up to 100 m; and the concentration decreased, following a nonlinear trend, with increasing height. Facades experiencing excessive concentrations were found to be mainly in the upwind areas for neighborhoods with 3 floor and 6 floor buildings, while in the downwind areas for those with 11 floor and 18 floor buildings. The median DLE was lower than three years, and only a few floor positions experienced a DLE of above 20 years. This study provides insight into pollutant dispersion patterns in typical neighborhoods, which is helpful to improve the early design.