Article
Thermodynamics
Shuxue Xu, Zihao Chu, Jianhui Niu, Guoyuan Ma
Summary: This study introduced a new room heating system using heat pipes and air source heat pumps as heat sources. The system could operate stably and provide a comfortable indoor temperature of 20 degrees Celsius under outdoor temperatures ranging from -1.5 to 3.3 degrees Celsius. Additionally, the heating coefficient of performance (COP) of the system could reach 4.35-4.64.
APPLIED THERMAL ENGINEERING
(2021)
Article
Construction & Building Technology
Zhihua Wang, Guichen Li, Fenghao Wang, Yujia Zhang
Summary: A transcritical CO2 air-source heat pump system was developed for space heating in China, with performance and feasibility compared in different climate zones. Results showed that the CO2 air-source heat pump had higher coefficient of performance and heating seasonal performance factor compared to the benchmark system.
JOURNAL OF BUILDING ENGINEERING
(2021)
Article
Construction & Building Technology
Wenlei Heng, Ziyun Wang, Yuling Wu
Summary: The experimental platform investigated the thermal storage capacity of phase change floor through different operation schemes and circulating water flow rates. The results demonstrated that the night operation scheme with appropriate water flow rate can achieve energy saving and peak regulation.
ENERGY AND BUILDINGS
(2021)
Article
Thermodynamics
Chenjiyu Liang, Xianting Li, Xiangjun Meng, Wenxing Shi, Junqiang Gu, Baolong Wang, Yanbo Lv
Summary: In this study, a new type of air source heat pump was developed to provide stable heating during defrosting by using multiple air source heat exchangers and anti-icing fluid pipelines. Test results showed that the heating capacity decay rate during defrosting can reach within 20%. After optimization, the heating capacity decay rate can be reduced to within 10%.
APPLIED THERMAL ENGINEERING
(2023)
Article
Environmental Sciences
Mustafa Mutlu
Summary: Isolating doors and windows to reduce heating energy costs can result in zero air change rate in certain environments. Comparisons were made between radiator and floor heating systems in rooms with zero air change rate, showing that floor heating systems were better at removing pollutants dispersed homogeneously in the room.
AEROSOL AND AIR QUALITY RESEARCH
(2021)
Article
Energy & Fuels
Jie Jia, Xuan Zhou, Wei Feng, Yuanda Cheng, Qi Tian, Fenglei Li, Yanjun Chen, W. L. Lee
Summary: This study introduces a new gravity-driven radiator as the indoor heating terminal of ASHP systems to improve energy efficiency and indoor comfort. Through field tests, the proposed system shows rapid thermal response and stable indoor environment with high energy efficiency. Results indicate that the proposed system outperforms hydraulic-based ASHP systems, with a significant increase in first law efficiency and exergy efficiency.
FRONTIERS IN ENERGY RESEARCH
(2021)
Article
Thermodynamics
Jie Lu, Yitian Tang, Zhiyuan Li, Guoqing He
Summary: This study compared the seasonal energy performance of serial and parallel configurations of solar-assisted heat pump systems in 39 cities across China. Results showed that a parallel system with ASHP as auxiliary source generally performs better, while a serial system is favored when electrical heating is the auxiliary source. High solar radiation and warm climates are beneficial for parallel configuration, while a more efficient WSHP favors the serial configuration.
APPLIED THERMAL ENGINEERING
(2021)
Article
Construction & Building Technology
Zongjiang Liu, Wei Xu, Zhong Li, Linhua Zhang, Ji Li, Aisong Li, Airong Feng
Summary: This study investigates the heating performance of radiators at low temperature based on laboratory test data and analyzes the deviation between predicted and actual values, confirming the engineering calculation accuracy. Various types of radiators were studied for their performance at low temperature, obtaining an attenuation rate of heat output at different conditions and presenting a correction coefficient table for selection. Using a TRNSYS platform, the heating effect of radiators was compared with floor radiant heating, showing similar results after number correction, proving the reasonableness of the low-temperature radiator correction.
JOURNAL OF BUILDING ENGINEERING
(2021)
Article
Energy & Fuels
Shuxue Xu, Jianhui Niu, Guoyuan Ma
Summary: This paper presents a new air source heat pump with multigroup heat pipe radiators (ASHPMP) system to solve the problems of low efficiency, complicated structure, freezing and bursting, and high energy consumption in the commonly used water loop system. Experimental results show that the system can operate stably under outdoor temperatures of -12.7°C to 6.5°C, and the heating coefficient of performance (heating COP) can reach up to 3.15 (at outdoor temperature -12.7°C) and 6.73 (at outdoor temperature 6.5°C) when the indoor temperature is set at 20°C.
Article
Green & Sustainable Science & Technology
Zhihua Wang, Yujia Zhang, Fenghao Wang, Guichen Li, Kaiwen Xu
Summary: This study focuses on addressing the issues encountered by CO2 air source heat pumps in space heating, by designing a heating system combined with thermal energy storage, optimizing its performance and analyzing its economy. The results show that the optimized system has increased costs but reduced annual operating costs, and improved the COP of the system by 7.4%.
Article
Construction & Building Technology
Wenzhe Wei, Chunsheng Wu, Long Ni, Wei Wang, Zongxi Han, Wenjun Zou, Yang Yao
Summary: In recent years, the application of air source heat pumps in centralized heating in North China has rapidly increased. However, there is a lack of theoretical investigation on the control methods of water pumps. This study established a mathematical model of variable-frequency air source heat pumps for heating and proposed three control methods for water pumps. The heating performance of the system and appropriate control methods for heating terminals were analyzed. The results showed that the power input of the water pump was the minimum in the pressure differential control method, and the power input of the ASHP system decreased by an average of 13.40% compared to the constant flow control method.
ENERGY AND BUILDINGS
(2022)
Article
Construction & Building Technology
Yang Wang, Wei He
Summary: The study proposes new approaches to accelerate the decarbonisation of domestic heating using heat pumps in the UK, including synthesising high-quality temporospatial energy datasets, a new framework for national-scale cost analysis, forward-looking analysis of potential subsidy structures and R&D directions. Currently RHI-subsidised ground source heat pumps have the lowest levelised cost of heat, but advances are needed to improve performance in various aspects.
ENERGY AND BUILDINGS
(2021)
Article
Construction & Building Technology
Yunseok Jang, Dongchan Lee, Jinyoung Kim, Se Hyeon Ham, Yongchan Kim
Summary: A waste-heat recovery water-source heat pump system has been proposed in this study, combining data centers and residential areas, which significantly reduces energy consumption, enhances system performance, and decreases CO2 emissions.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Construction & Building Technology
Jian Liu, Xue Tian, Zhang Lin
Summary: A novel dual heat source warm-air heating system (DWAHS) was developed in this study, utilizing a dual heat source air source heat pump to simultaneously supply 35°C and 60°C hot water, significantly reducing exergy loss. Eco-friendly refrigerants were used to improve system performance.
BUILDING AND ENVIRONMENT
(2021)
Article
Energy & Fuels
Yu-Jin Hwang, Jae-Weon Jeong
Summary: The research aims to optimize the operation ratio of radiant floor heating and air source heat pump systems, achieving significant energy savings and improved thermal comfort. Results show that a suitable floor temperature can be between 22-23 degrees C, leading to energy savings of 31.5-37.6% compared to using radiant floor heating alone.
Article
Construction & Building Technology
Jun Shinoda, Angelos Mylonas, Ongun B. Kazanci, Shin-ichi Tanabe, Bjarne W. Olesen
Summary: Wireless sensors are increasingly used in HVAC systems for their flexibility in positioning, with conventional wired sensors measuring closer to globe temperature sensors than commonly assumed. In high load settings, measurements in radiant systems show smaller deviations from reference sensors compared to all-air systems.
ENERGY AND BUILDINGS
(2021)
Article
Construction & Building Technology
Shady Attia, Ronnen Levinson, Eileen Ndongo, Peter Holzer, Ongun Berk Kazanci, Shabnam Homaei, Chen Zhang, Bjarne W. Olesen, Dahai Qi, Mohamed Hamdy, Per Heiselberg
Summary: The concept of climate resilience in building cooling design requires a clear definition and framework of key concepts before implementation. Critical issues include disruptions or climatic shocks, built domain scale, resilience timeline, disruption events, stages of resilience, indoor climate limits, and influencing factors. The paper suggests a definition and criteria for vulnerability, resistance, robustness, and recoverability to develop performance-driven indicators for passive and active cooling solutions against disruptions.
ENERGY AND BUILDINGS
(2021)
Article
Construction & Building Technology
Pawel Wargocki, Wenjuan Wei, Jana Bendzalova, Carlos Espigares-Correa, Christophe Gerard, Olivier Greslou, Mathieu Rivallain, Marta Maria Sesana, Bjarne W. Olesen, Johann Zirngibl, Corinne Mandin
Summary: The EPBD mandates Member States to support energy performance upgrades of existing buildings for a healthier indoor environment. The TAIL rating scheme was developed to address the lack of a widely accepted method for rating overall IEQ. By standardizing the rating of thermal, acoustic, indoor air, and luminous environments, the scheme provides a comprehensive assessment of IEQ levels.
ENERGY AND BUILDINGS
(2021)
Article
Construction & Building Technology
Jose Joaquin Aguilera, Dragos-Ioan Bogatu, Ongun Berk Kazanci, Charalampos Angelopoulos, Daniel Coakley, Bjarne W. Olesen
Summary: A control framework for mixed-mode buildings was defined based on the adaptive comfort model and PMV-PPD method, tested using simulation analysis of an office building module, and shown to reduce energy use by 12-51% compared to mechanically cooled buildings. Utilizing the upper limit of the adaptive comfort zone as cooling set point led to additional energy savings and fewer switchovers between operation modes, demonstrating the potential for large reductions in energy use without compromising comfort or indoor air quality in mixed-mode buildings.
ENERGY AND BUILDINGS
(2021)
Article
Construction & Building Technology
Dragos-Ioan Bogatu, Ongun B. Kazanci, Bjarne W. Olesen
Summary: This study investigated a novel macro-encapsulated PCM panel (MEP) with embedded pipes as an active ceiling cooling component, compared to commercially available radiant cooling technologies. The MEP showed high specific cooling power and performance close to radiant ceiling panels, providing a thermal environment within Category II of EN16798 for 83% of the occupied time.
ENERGY AND BUILDINGS
(2021)
Article
Construction & Building Technology
Zheng Li, Qingwen Zhang, Ongun Berk Kazanci, Feng Fan, Bjarne W. Olesen
Summary: This study investigated group differences in human perceptions in 22 open-plan offices in Harbin, China. The findings revealed gender, age, education level, BMI, and the location of subjects as factors influencing human comfort. Differences in comfort temperatures, comfort votes, and reactions to indoor environmental parameters were analyzed among different groups.
BUILDING AND ENVIRONMENT
(2022)
Review
Construction & Building Technology
Runming Yao, Shaoxing Zhang, Chenqiu Du, Marcel Schweiker, Simon Hodder, Bjarne W. Olesen, Jorn Toftum, Francesca Romana D'Ambrosio, Hansjuergen Gebhardt, Shan Zhou, Feng Yuan, Baizhan Li
Summary: This paper reviews the historical evolution of thermal comfort research, focusing on adaptive thermal comfort studies and evaluating representative prediction models. Based on the analysis, three thermal environment assessment approaches are classified and their strengths and constraints are analyzed.
BUILDING AND ENVIRONMENT
(2022)
Article
Multidisciplinary Sciences
Bing Dong, Yapan Liu, Wei Mu, Zixin Jiang, Pratik Pandey, Tianzhen Hong, Bjarne Olesen, Thomas Lawrence, Zheng O'Neil, Clinton Andrews, Elie Azar, Karol Bandurski, Ronita Bardhan, Mateus Bavaresco, Christiane Berger, Jane Burry, Salvatore Carlucci, Karin Chvatal, Marilena De Simone, Silvia Erba, Nan Gao, Lindsay T. Graham, Camila Grassi, Rishee Jain, Sanjay Kumar, Mikkel Kjaergaard, Sepideh Korsavi, Jared Langevin, Zhengrong Li, Aleksandra Lipczynska, Ardeshir Mahdavi, Jeetika Malik, Max Marschall, Zoltan Nagy, Leticia Neves, William O'Brien, Song Pan, June Young Park, Ilaria Pigliautile, Cristina Piselli, Anna Laura Pisello, Hamed Nabizadeh Rafsanjani, Ricardo Forgiarini Rupp, Flora Salim, Stefano Schiavon, Jens Schwee, Andrew Sonta, Marianne Touchie, Andreas Wagner, Sinead Walsh, Zhe Wang, David M. Webber, Da Yan, Paolo Zangheri, Jingsi Zhang, Xiang Zhou, Xin Zhou
Summary: This paper presents a global database on building occupant behavior, which includes 34 datasets collected from various countries and institutions. These datasets provide more realistic inputs for building energy simulation and load forecasting.
Article
Energy & Fuels
Francesca Romana d'Ambrosio Alfano, Bjarne Wilkens Olesen, Daniela Pepe, Boris Igor Palella
Summary: Energy consumption calculations and thermal comfort conditions assessment are crucial in building simulations with BEPS tools. Different software validation and operating conditions can lead to inconsistent predictions. This study clarifies building model preparation and input data definition for using different software. It also compares the energy and temperature output of two BEPS tools for the same building under the same weather conditions, showing differences in temperature values but agreement in energy predictions.
Article
Construction & Building Technology
Xiaowen Su, Ongun Berk Kazanci, Zhaojun Wang, Bjarne W. Olesen, Liangliang Sun, Yanping Yuan
Summary: This study emphasizes the importance of a unified quantitative index for non-uniform environments and adopts the equivalent temperature (teq) as an integral evaluation index. The study analyzes data from laboratory measurements of different types of non-uniform environments in offices and vehicles, and develops a new teq comfort chart. The results show that overall sensible heat loss of the human body remained constant, but local thermal discomfort and sensation changed with non-uniform environments.
BUILDING AND ENVIRONMENT
(2023)
Article
Construction & Building Technology
Shahla Ghaffari Jabbari, Zora Vrcelj, Hing-Wah Chau, Aida Maleki, Bjarne W. Olesen
Summary: This study investigated the impact of individual differences and heating system types on perceived thermal comfort, neutral temperature, and thermal sensitivity in cold outdoor conditions. Results showed that temperament and thermal past experience directly affected occupants' thermal preference and influenced thermal sensation indirectly through clothing level. The type of heating system had the greatest impact on neutral temperature. Individual factors did not directly influence neutral temperature, but thermal sensitivity was influenced by temperament. Control over the heating system could lead to thermal adaptation at lower temperatures.
JOURNAL OF ARCHITECTURAL ENGINEERING
(2023)
Review
Construction & Building Technology
Dragos-Ioan Bogatu, Jun Shinoda, Jose Joaquin Aguilera, Bjarne W. Olesen, Futa Watanabe, Yosuke Kaneko, Ongun B. Kazanci
Summary: There are standardized methods for assessing thermal comfort, but subjective evaluation is still the only reliable method to determine individual comfort. Personal comfort models using machine learning have shown promising results in predicting thermal response. The challenge lies in identifying relevant indicators and finding a simple way to acquire them. Integrating anthropometric and physiological data could enhance the performance of personal comfort models. However, implementing automatic control using physiological indicators still faces challenges in establishing acceptable thresholds and identifying the optimal set of indicators and their combinations.
BUILDING AND ENVIRONMENT
(2023)
Article
Construction & Building Technology
Kan Shindo, Jun Shinoda, Ongun B. Kazanci, Dragos-Ioan Bogatu, Shin-ichi Tanabe, Bjarne W. Olesen
Summary: There is an urgent need to reduce carbon emissions from the building sector. This study compares the whole life carbon emissions of different HVAC systems in a case study in Denmark. The study finds that the Thermally Active Building System (TABS) has lower operational carbon emissions and whole life carbon emissions compared to the all-air system.
ENERGY AND BUILDINGS
(2023)
Article
Construction & Building Technology
L. Zaniboni, M. Sarey Khanie, G. Pernigotto, J. Toftum, A. Gasparella, B. W. Olesen
Summary: The satisfaction of occupants is positively influenced by daylight access, but issues still exist with artificial lighting levels. Therapists tend to assess their environmental perception more globally and show more concern about light and daylight satisfaction when comfort issues are present.
LIGHTING RESEARCH & TECHNOLOGY
(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)
