Thermal comfort modelling and empirical validation of predicted air temperature in hot-summer Mediterranean courtyards

The street thermal environment is important for thermal comfort, urban climate and pollutant dispersion. A 24-h vehicle traverse study was conducted over the Kowloon Peninsula of Hong Kong in summer, with each measurement period consisting of 2–3 full days. The data covered a total of 158 loops in 198 h along the route on sunny days. The measured data were averaged by three methods (direct average, FFT filter and interpolated by the piecewise cubic Hermite interpolation). The average street air temperatures were found to be 1–3 °C higher than those recorded at nearby fixed weather stations. The street warming phenomenon observed in the study has substantial implications as usually urban heat island (UHI) intensity is estimated from measurement at fixed weather stations, and therefore the UHI intensity in the built areas of the city may have been underestimated. This significant difference is of interest for studies on outdoor air temperature, thermal comfort, urban environment and pollutant dispersion. The differences were simulated by an improved one-dimensional temperature model (ZERO-CAT) using different urban morphology parameters. The model can correct the underestimation of street air temperature. Further sensitivity studies show that the building arrangement in the daytime and nighttime plays different roles for air temperature in the street. City designers can choose different parameters based on their purpose.

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Energy-saving potential of intermittent heating system: Influence of composite phase change wall and optimization strategy

Energy Exploration & Exploitation ◽

10.1177/0144598720969217 ◽

2020 ◽

pp. 014459872096921

Author(s):

Yanru Li ◽

Enshen Long ◽

Lili Zhang ◽

Xiangyu Dong ◽

Suo Wang

Keyword(s):

Energy Consumption ◽

Thermal Comfort ◽

Phase Change ◽

Air Temperature ◽

Indoor Air ◽

Thermal Environment ◽

Optimization Strategy ◽

Indoor Thermal Environment ◽

Indoor Thermal Comfort ◽

Intermittent Heating

In the Yangtze River zone of China, the heating operation in buildings is mainly part-time and part-space, which could affect the indoor thermal comfort while making the thermal process of building envelope different. This paper proposed to integrate phase change material (PCM) to building walls to increase the indoor thermal comfort and attenuate the temperature fluctuations during intermittent heating. The aim of this study is to investigate the influence of this kind of composite phase change wall (composite-PCW) on the indoor thermal environment and energy consumption of intermittent heating, and further develop an optimization strategy of intermittent heating operation by using EnergyPlus simulation. Results show that the indoor air temperature of the building with the composite-PCW was 2–3°C higher than the building with the reference wall (normal foamed concrete wall) during the heating-off process. Moreover, the indoor air temperature was higher than 18°C and the mean radiation temperature was above 20°C in the first 1 h after stopping heating. Under the optimized operation condition of turning off the heating device 1 h in advance, the heat release process of the composite-PCW to the indoor environment could maintain the indoor thermal environment within the comfortable range effectively. The composite-PCW could decrease 4.74% of the yearly heating energy consumption compared with the reference wall. The optimization described can provide useful information and guidance for the energy saving of intermittently heated buildings.

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THE EFFECTS OF VERTICAL AIR TEMPERATURE DEFFERENCES ON THERMAL COMFORT AND PHYSIOLOGICAL RESPONSES

Journal of Architecture Planning and Environmental Engineering (Transactions of AIJ) ◽

10.3130/aijax.417.0_31 ◽

1990 ◽

Vol 417 (0) ◽

pp. 31-42

Author(s):

Kazuaki BOHGAKI ◽

Nozomu IMAGAWA ◽

Hiroyasu ITOH ◽

Masato OHMORI ◽

Shigeru YAMADA

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Physiological Responses

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An Interactive Task Conditioning System Featuring Personal Comfort Models and Non-Intrusive Sensing Techniques: A Field Study in Shanghai

Technologies ◽

10.3390/technologies9040090 ◽

2021 ◽

Vol 9 (4) ◽

pp. 90

Author(s):

Siliang Lu ◽

Erica Cochran Hameen

Keyword(s):

Thermal Comfort ◽

Field Study ◽

Air Temperature ◽

Indoor Air ◽

Thermal Environment ◽

Thermal Sensation ◽

New Paradigm ◽

Dynamic Task ◽

Current Task ◽

Open Plan

Heating, ventilation and air-conditioning (HVAC) systems play a key role in shaping office environments. However, open-plan office buildings nowadays are also faced with problems like unnecessary energy waste and an unsatisfactory shared indoor thermal environment. Therefore, it is significant to develop a new paradigm of an HVAC system framework so that everyone could work under their preferred thermal environment and the system can achieve higher energy efficiency such as task ambient conditioning system (TAC). However, current task conditioning systems are not responsive to personal thermal comfort dynamically. Hence, this research aims to develop a dynamic task conditioning system featuring personal thermal comfort models with machine learning and the wireless non-intrusive sensing system. In order to evaluate the proposed task conditioning system performance, a field study was conducted in a shared office space in Shanghai from July to August. As a result, personal thermal comfort models with indoor air temperature, relative humidity and cheek (side face) skin temperature have better performances than baseline models with indoor air temperature only. Moreover, compared to personal thermal satisfaction predictions, 90% of subjects have better performances in thermal sensation predictions. Therefore, personal thermal comfort models could be further implemented into the task conditioning control of TAC systems.

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Assessing The Thermal Comfort Conditions In Open Spaces: A Transversal Field Survey On The University Campus In India

International Journal of Built Environment and Sustainability ◽

10.11113/ijbes.v8.n3.786 ◽

2021 ◽

Vol 8 (3) ◽

pp. 77-92

Author(s):

Pardeep Kumar ◽

Amit Sharma

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Arid Regions ◽

Thermal Sensation ◽

Probit Analysis ◽

Outdoor Thermal Comfort ◽

Cold Weather ◽

Open Spaces ◽

Physiological Equivalent Temperature ◽

Preferred Temperature

Outdoor thermal comfort (OTC) promotes the usage frequency of public places, recreational activities, and people's wellbeing. Despite the increased interest in OTC research in the past decade, less attention has been paid to OTC research in cold weather, especially in arid regions. The present study investigates the OTC conditions in open spaces at the campus area in the arid region. The study was conducted by using subjective surveys(questionnaire) and onsite monitoring (microclimate parameters). The study was conducted at the Deenbandhu Chhotu Ram University of Science and Technology, Murthal, Haryana-India campus during the cold season of 2019. The timings of surveys were between 9:00 and 17:00 hours. The authors processed the 185 valid questionnaire responses of the respondents to analyze OTC conditions. Only 8.6% of the respondents marked their perceived sensation "Neutral." Regression analysis was applied between respondents' thermal sensations and microclimate parameters to develop the empirical thermal sensation model. The air temperature was the most dominant parameter affecting the sensations of the respondents. The empirical model indicated that by increasing air temperature, relative humidity, and solar radiation, the thermal sensations also increased while wind speed had an opposite effect. Physiological equivalent temperature (PET) was applied for assessing the OTC conditions; the neutral PET range was found to be 18.42-25.37°C with a neutral temperature of 21.89°C. The preferred temperature was 21.99 °C by applying Probit analysis. The study's findings could provide valuable information in designing and planning outdoor spaces for educational institutions in India's arid regions

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Human Thermal Comfort Situation in the Goller (Lakes) District of Turkey

New Trends and Issues Proceedings on Advances Pure and Applied Sciences ◽

10.18844/gjpaas.v0i7.3172 ◽

2016 ◽

pp. 137-144

Author(s):

Yuksel Guclu

Keyword(s):

Relative Humidity ◽

Thermal Comfort ◽

Human Health ◽

Air Temperature ◽

Mediterranean Region ◽

Human Thermal Comfort ◽

Almost All ◽

Relative Humidity Data ◽

Recreation Activities

Abstract In this study, the determination of the human thermal comfort situation in the Goller District (in the Mediterranean Region) of Turkey has been aimed. In the direction of the aim, the air temperature and relative humidity data of total 11 meteorology stations have been examined according to The Thermo-hygrometric Index (THI) and the New Summer Simmer Index (SSI). According to this, it has been determined that the thermal comfort conditions are not appropriate in the period of October-May on average monthly. The months of June and September are the most appropriate to almost all kinds of tourism and recreation activities in the outdoor in terms of thermal comfort. When THI and SSI indices’ values are evaluated together, the periods between 5th – 25th June and 29th August-16th September are the most appropriate periods in the study area on average in terms of the thermal comfort for the tourism and recreation activities in the outdoor. Keywords: Thermal comfort, human health, The Thermo-Hygrometric Index, The Summer Simmer Index, Goller District, Turkey.

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Personal Atmosphere: Estimation of Air Conditioner Parameters for Personalizing Thermal Comfort

Applied Sciences ◽

10.3390/app10228067 ◽

2020 ◽

Vol 10 (22) ◽

pp. 8067

Author(s):

Tomohiro Mashita ◽

Tetsuya Kanayama ◽

Photchara Ratsamee

Keyword(s):

Machine Learning ◽

Thermal Comfort ◽

Air Temperature ◽

Fine Tuning ◽

Air Conditioner ◽

Data Set ◽

Air Conditioning System ◽

Air Conditioners ◽

Uniform Distributions ◽

Machine Learning Model

Air conditioners enable a comfortable environment for people in a variety of scenarios. However, in the case of a room with multiple people, the specific comfort for a particular person is highly dependent on their clothes, metabolism, preference, and so on, and the ideal conditions for each person in a room can conflict with each other. An ideal way to resolve these kinds of conflicts is an intelligent air conditioning system that can independently control air temperature and flow at different areas in a room and then produce thermal comfort for multiple users, which we define as the personal preference of air flow and temperature. In this paper, we propose Personal Atmosphere, a machine learning based method to obtain parameters of air conditioners which generate non-uniform distributions of air temperature and flow in a room. In this method, two dimensional air-temperature and -flow distributions in a room are used as input to a machine learning model. These inputs can be considered a summary of each user’s preference. Then the model outputs a parameter set for air conditioners in a given room. We utilized ResNet-50 as the model and generated a data set of air temperature and flow distributions using computational fluid dynamics (CFD) software. We then conducted evaluations with two rooms that have two and four air conditioners under the ceiling. We then confirmed that the estimated parameters of the air conditioners can generate air temperature and flow distributions close to those required in simulation. We also evaluated the performance of a ResNet-50 with fine tuning. This result shows that its learning time is significantly decreased, but performance is also decreased.

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Importance of Behavioral Adjustments for Adaptive Thermal Comfort in a Condominium with HEMS System

Journal of the Institute of Engineering ◽

10.3126/jie.v15i3.32175 ◽

2020 ◽

Vol 15 (3) ◽

pp. 163-170

Author(s):

Rajan KC ◽

Hom Bahadur Rijal ◽

Masanori Shukuya ◽

Kazui Yoshida

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Energy Use ◽

Thermal Environment ◽

Residential Buildings ◽

Outdoor Environment ◽

Adaptive Behaviors ◽

Outdoor Air ◽

Indoor Thermal Environment ◽

Indoor Thermal Comfort

The energy use in residential dwellings has been increasing due to increasing use of modern electric appliances to make the lifestyle easier, entertaining and better. One of the major purposes of indoor energy use is for improving indoor thermal environment for adjusting thermal comfort. Along with the use of passive means like the use of mechanical devices, the occupants in any dwellings use active means such as the use of natural ventilation, window opening, and clothing adjustment. In fact, the use of active means when the outdoor environment is good enough might be more suitable to improve indoor thermal environment than the use of mechanical air conditioning units, which necessarily require electricity. Therefore, the people in developing countries like Nepal need to understand to what extent the occupants can use active means to manage their own indoor thermal comfort. The use of active means during good outdoor environment might be an effective way to manage increasing energy demand in the future. We have made a field survey on the occupants’ adaptive behaviors for thermal comfort in a Japanese condominium equipped with Home Energy Management System (HEMS). Online questionnaire survey was conducted in a condominium with 356 families from November 2015 to October 2016 to understand the occupants’ behaviors. The number of 17036 votes from 39 families was collected. The indoor air temperature, relative humidity and illuminance were measured at the interval of 2-10 minutes to know indoor thermal environmental conditions. The occupants were found using different active behaviors for thermal comfort adjustments even in rather harsh summer and winter. Around 80% of the occupants surveyed opened windows when the outdoor air temperature was 30⁰C in free running (FR) mode and the clothing insulation was 0.93 clo when the outdoor air temperature was 0⁰C. The result showed that the use of mechanical heating and cooling was not necessarily the first priority to improve indoor thermal environment. Our result along with other results in residential buildings showed that the adaptive behaviors of the occupants are one of the primary ways to adjust indoor thermal comfort. This fact is important in enhancing the energy saving building design.

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