Article
Environmental Sciences
Sunil Kumar, Maria D. King
Summary: COVID-19 spreads through air and HVAC approach can reduce virus spread. By simulating the diffusion of virus-laden droplets under different HVAC configurations, this study finds that low-speed air curtains can effectively remove aerosolized droplets, reducing the spread of disease.
ENVIRONMENTAL RESEARCH
(2022)
Article
Construction & Building Technology
Chen Ren, Hao-Cheng Zhu, Shi-Jie Cao
Summary: This study compared several ventilation strategies in offices and found that stratum ventilation showed the best performance in mitigating the spread of infectious diseases.
Article
Construction & Building Technology
MinHo Kim, Hyung-Jun Park
Summary: The study proposes a new approach based on artificial neural network (ANN) for predicting thermodynamic parameters in an indoor environment. The approach consists of two independently trained ANN models, where the outputs of the first model are used as inputs to the second model. The predicted velocity distribution from the first model is employed as an additional input for the second model. The proposed approach outperforms existing ANN models and provides a reasonable solution for indoor airflow prediction.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Environmental Sciences
Yun Hu, Yihui Wu, Qun Wang, Jian Hang, Qingman Li, Jie Liang, Hong Ling, Xuelin Zhang
Summary: This paper evaluates the impacts of indoor-outdoor temperature differences on building ventilation and indoor-outdoor air pollutant dispersion in urban areas. The results show that cross ventilation increases the air change rate and mitigates the environmental health stress for the indoor environment.
Article
Construction & Building Technology
Yun Kyu Yi, Manal Anis, Keun Jang, You-Jeong Kim
Summary: The recent global pandemic highlights the importance of natural ventilation in reducing energy consumption and airborne contamination. This research aims to improve natural ventilation in classrooms with one-sided openings through the design of window wing walls and the utilization of data-driven design and Computational Fluid Dynamics (CFD) simulations.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Energy & Fuels
Yongliang Shen, Abdur Rehman Mazhar, Pengwei Zhang, Shuli Liu
Summary: The cascaded latent heat storage (CLHS) system is favored for its remarkable heat transfer rate and heat storage capacity. In previous studies, the influence of PCM volume distribution on the system performance has been overlooked. This study optimizes the volume distribution of CLHS system and shows that the heat storage performance can be improved. The performance indicator, charged exergy, exhibits more benefits with a more uniform PCM volume distribution.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Construction & Building Technology
Arman Ameen, Mathias Cehlin, Haruna Yamasawa, Tomohiro Kobayashi, Taghi Karimipanah
Summary: The performance of a corner based impinging jet ventilation system (CIJV) in an office environment was numerically evaluated, considering both local thermal comfort and indoor air quality. The results showed that CIJV outperforms a traditional mixing system in terms of indoor air quality. It was also found that CIJV creates a stronger temperature stratification in summertime compared to wintertime. The energy saving potential of CIJV was assessed, and a possible reduction of 7%, 8%, and 9% in ventilation flowrate was observed for different outdoor temperature ranges.
DEVELOPMENTS IN THE BUILT ENVIRONMENT
(2023)
Article
Construction & Building Technology
Ihab Hasan Hatif, Haslinda Mohamed Kamar, Nazri Kamsah, Keng Yinn Wong
Summary: This study compares the effectiveness of different air distribution systems, including mixing ventilation (MV), displacement ventilation (DV), and stratum ventilation (SV), and evaluates specific influencing factors for each system. The results show that no single system consistently outperforms others, and the effectiveness depends on different conditions. DV and SV systems may have higher infection risks in certain situations, while MV systems are recommended for use when people's locations and relative positions are unclear.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Yuanyuan Wang, Yanzhe Yu, Tianzhen Ye, Quan Bo
Summary: This study systematically compared the ventilation characteristics of different window-opening forms using CFD simulations, and found that a sliding window with a full opening has the highest discharge coefficients under wind-driven cross-ventilation and temperature-driven single-sided ventilation. Additionally, top-hung windows opening both inwards and outwards showed better ventilation performance than other window types under the two ventilation modes.
APPLIED SCIENCES-BASEL
(2021)
Article
Thermodynamics
Tianyi Zhang, Lei Chen, Jin Wang
Summary: The application of machine learning, specifically neural networks (NNs) and genetic algorithm (GA), is studied for multi-objective optimization of heat exchangers. Taking the tube fin heat exchanger (TFHE) as the research object, the study optimizes the inlet air velocity and tube ellipticity. Computational Fluid Dynamics (CFD) simulation is used to obtain optimal heat transfer performance and pressure drop performance for different Reynolds and tube ellipticity values. The simulation data is then used to train Back-Propagation neural networks and establish prediction models for heat transfer coefficient and pressure drop. The non-dominated multi-objective genetic algorithm (NSGA-II) is employed to optimize the NNs' prediction results. The optimization results show significant improvements in pressure drop and heat transfer coefficient for specific Reynolds and ellipticity values.
Article
Energy & Fuels
Ewa Zender-Swiercz
Summary: The study analyzed a decentralized ventilation unit in a building facade and conducted Computational Fluid Dynamics (CFD) simulations under real conditions, demonstrating its effectiveness in improving indoor microclimate by reducing carbon dioxide concentration and maintaining indoor air temperature.
Article
Construction & Building Technology
Zhaoji Wu, Yufeng Zhang, Jinbo Mai, Fulin Wang, Yongchao Zhai, Zhongjun Zhang
Summary: In this study, a new adaptation-based control with night ventilation (NV) was proposed and tested in an office building in hot-humid areas. The results showed that the adaptation-based control could reduce energy consumption, and the addition of NV further improved the energy-saving effect.
BUILDING AND ENVIRONMENT
(2023)
Article
Thermodynamics
Peng-Yi Cui, Wei-Qiu Chen, Jia-Qi Wang, Jin-Hao Zhang, Yuan-Dong Huang, Wen-Quan Tao
Summary: This study investigated the Re-independence of indoor airflow and pollutant dispersion within an isolated building using numerical models validated by wind-tunnel experiments. The critical Reynolds number for indoor flow and turbulent diffusion was found to be position-dependent and should be suggested as the optimal value at the most unfavorable position. The study recommends different critical Reynolds numbers for outdoor and indoor flows, and emphasizes that indoor pollutant diffusion is completely determined by flow structures.
BUILDING SIMULATION
(2022)
Article
Construction & Building Technology
Arturs Staveckis, Anatolijs Borodinecs
Summary: This study investigates the effectiveness of impinging jet ventilation system in providing desired indoor climate in office buildings through experiments and CFD simulations. Results show that the shape of the air opening has little impact on contaminant and heat removal effectiveness, while circular air openings perform better.
ENERGY AND BUILDINGS
(2021)
Article
Construction & Building Technology
Tianhu Zhang, Yuxin Zhang, Aoqi Li, Yi Gao, Yandi Rao, Qingxin Zhao
Summary: Ventilation is an effective method for removing indoor air pollutants, and the computational fluid dynamics (CFD) method provides an efficient approach to studying the removal efficiency. However, the CFD method is often constrained by long computational times. This study investigates the kinetic characteristic of air pollutant removal by ventilation to reduce computational time. The results show that the Langmuir-Hinshelwood (L-H) kinetic model accurately predicts the removal efficiency of VOCs in the absence of barriers, while the removal of particulate matter is less accurately predicted. The L-H kinetic model is a useful tool for designing ventilation strategies when airflow-determined pollutants are present.
BUILDING AND ENVIRONMENT
(2022)
Article
Construction & Building Technology
Parth Bansal, Steven Jige Quan
Summary: This study investigates the relationship between urban form and canopy layer urban heat island (CUHI) using a relatively large sample of microclimate sensors in Seoul, Korea. The study compares different statistical models and finds that the spatially explicit gradient boosting decision tree (GBDT) model has the highest accuracy. The study also shows that the effect of urban form on CUHI varies at different time instances during the day. These findings provide valuable insights for planners to understand the complexity of urban climate and reduce CUHI magnitude.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Miaomiao Liu, Salah Almazmumi, Pinlu Cao, Carlos Jimenez-bescos, John Kaiser Calautit
Summary: Windcatchers provide effective low-energy ventilation and summer passive cooling in temperate climates. However, their use in winter is limited due to significant ventilation heat loss and potential discomfort. This study evaluates the applicability of windcatchers in low-temperature conditions, highlighting the need for control strategies to reduce over-ventilation and the integration of heat recovery or thermal storage to enhance winter thermal conditions.
BUILDING AND ENVIRONMENT
(2024)
Review
Construction & Building Technology
Behrouz Nourozi, Aneta Wierzbicka, Runming Yao, Sasan Sadrizadeh
Summary: This article presents a systematic review of ventilation solutions in hospital wards, aiming to enhance pathogen removal performance while maintaining patient and healthcare staff comfort using air-cleaning techniques. The study reveals the importance of proper ventilation systems in reducing infection risk and adverse effects of cross-contamination.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Zhen Yang, Weirong Zhang, Hongkai Liu, Weijia Zhang, Mingyuan Qin
Summary: The study examines the influence of personalized local heating on the thermal comfort of occupants in old residential buildings. The findings reveal that personalized local heating can increase the overall thermal sensation of occupants, but only a few methods are effective in enhancing thermal comfort. The chosen heating methods and background temperature affect the participants' selection of heating parts.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Hong Cheng, Dan Norback, Huilin Zhang, Liu Yang, Baizhan Li, Yinping Zhang, Zhuohui Zhao, Qihong Deng, Chen Huang, Xu Yang, Chan Lu, Hua Qian, Tingting Wang, Ling Zhang, Wei Yu, Juan Wang, Xin Zhang
Summary: The home environment and sick building syndrome (SBS) symptoms in five southern Chinese cities have been studied over time. The study found a decrease in asthma prevalence and an increase in allergic rhinitis. Cockroaches, rats, mice, mosquitoes or flies were identified as consistent biological risk factors for SBS symptoms, while redecoration, buying new furniture, and traffic air pollution were identified as other risk factors.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Chaojie Xing, Zhengtao Ai, Zhiwei Liu, Cheuk Ming Mak, Hai Ming Wong
Summary: This study experimentally investigated the emission characteristics of droplets around the mouth during dental treatments. The results showed that the peak mass fraction of droplets occurs within the size range of 20 μm to 100 μm, and droplets with a diameter less than 200 μm account for over 80% of the mass fraction. The dominant emission direction of droplets is towards the dummy's head and chest, forming an approximately cone shape.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Zhijian Liu, Zhe Han, Lina Hu, Chenxing Hu, Rui Rong
Summary: This study compared the effects of different respiratory behaviors on the distribution of aerosols in a ward and the risk of infection for healthcare workers using numerical simulation. It was found that talking in the ward significantly increased aerosol concentrations, particularly short periods of talking. Wards designed with side-supply ventilation had lower overall infection risk. Talking alternately between healthcare workers and patients slightly extended the impact time of aerosols.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Yan Yan, Mengyuan Kang, Haodong Zhang, Zhiwei Lian, Xiaojun Fan, Chandra Sekhar, Pawel Wargocki, Li Lan
Summary: In a high-density city, opening windows for sleep may lead to increased indoor temperature, higher PM2.5 concentration, and noise disturbance, which can negatively impact sleep quality.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Yan Bai, Liang Liu, Kai Liu, Shuai Yu, Yifan Shen, Di Sun
Summary: This study developed a non-intrusive personal thermal comfort model using machine learning techniques combined with infrared facial recognition. The results showed that the ensemble learning models perform better than traditional models, and the broad learning model has a higher prediction precision with lower computational complexity and faster training speed compared to deep neural networks. The findings provide a reference for optimizing building thermal environments.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Yue Lei, Zeynep Duygu Tekler, Sicheng Zhan, Clayton Miller, Adrian Chong
Summary: Mixed-mode ventilation is a promising solution for achieving energy-efficient and comfortable indoor environments. This study found that occupants can thermally adapt when switching between natural ventilation (NV) and air-conditioning (AC) modes within the same day, with the adaptation process stabilizing between 35 to 45 minutes after the mode switch. These findings are important for optimizing thermal comfort in mixed-mode controls, considering the dynamic nature of thermal adaptation.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Nan Mo, Jie Han, Yingde Yin, Yelin Zhang
Summary: This study develops a method based on the LCZ framework for a comprehensive evaluation of urban-scale heat island effects, considering the impact of geographic factors on LST. The results show that Guilin's geomorphological conditions lead to abnormal heat island effects during winter, and the cooling effects of mountains and water bodies vary seasonally in different built areas, with LCZ 2 exhibiting the strongest cooling effect.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Tunga Salthammer
Summary: Monitoring the potential formaldehyde emission of wood-based materials through test chamber investigations has significantly contributed to reducing indoor formaldehyde concentrations. However, the different methodologies used in these procedures prevent direct result comparison. Empirical models for converting formaldehyde steady-state concentrations based on temperature, humidity, air change rate, and loading were developed in the 1970s and have been modified to accommodate the development of lower-emitting materials. Formaldehyde emissions from wood-based materials are complex and require nonlinear regression tools for mathematical analysis.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Katarina Stebelova, Katarina Kovacova, Zuzana Dzirbikova, Peter Hanuliak, Tomas Bacigal, Peter Hartman, Andrea Vargova, Jozef Hraska
Summary: This study investigated the impact of reduced short-wavelength light on the hormone melatonin metabolite 6-sulfatoxymelatonin (u-sMEL) and examined the association between previous day's light exposure and u-sMEL. It was found that reducing short-wavelength light during the day did not change the concentration of u-sMEL. Personal photopic illuminance was positively correlated with u-sMEL in the reference week. The illuminance had a significant impact on u-sMEL, as shown by the evaluation of the mean of all three urine samples. However, this correlation was not found in the experimental week.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Ruoxin Xiong, Ying Shi, Haoming Jing, Wei Liang, Yorie Nakahira, Pingbo Tang
Summary: This study proposes a data-model integration method to identify and calibrate uncertainties in machine learning models, leading to improved thermal perception predictions. The method utilizes the Multidimensional Association Rule Mining algorithm to identify biased human responses and enhances prediction accuracy and reliability. The study also evaluates different calibration techniques and discovers their potential in enhancing prediction reliability.
BUILDING AND ENVIRONMENT
(2024)
Article
Construction & Building Technology
Beichao Hu, Zeda Yin, Abderrachid Hamrani, Arturo Leon, Dwayne McDaniel
Summary: This paper introduces an innovative super-resolution approach to model the air flow and temperature field in the cold aisle of a data center. The proposed method reconstructs a high-fidelity flow field by using a low-fidelity flow field, significantly reducing the computational time and enabling real-time prediction.
BUILDING AND ENVIRONMENT
(2024)