COMPARISON OF INDOOR AIR TEMPERATURE AND OPERATIVE TEMPERATURE -DRIVEN HVAC SYSTEMS BY MEANS OF THERMAL COMFORT AND ENERGY CONSUMPTION

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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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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Experimental study on coupling effect of indoor air temperature and radiant temperature on human thermal comfort in non-uniform thermal environment

Building and Environment ◽

10.1016/j.buildenv.2019.106387 ◽

2019 ◽

Vol 165 ◽

pp. 106387 ◽

Cited By ~ 3

Author(s):

Dengjia Wang ◽

Guixia Chen ◽

Cong Song ◽

Yanfeng Liu ◽

Wenfang He ◽

...

Keyword(s):

Experimental Study ◽

Thermal Comfort ◽

Air Temperature ◽

Indoor Air ◽

Thermal Environment ◽

Coupling Effect ◽

Human Thermal Comfort ◽

Radiant Temperature

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Comparative thermal performance of static sunshade and brick cavity wall for energy efficient building envelope in composite climate

Thermal Science ◽

10.2298/tsci1403925c ◽

2014 ◽

Vol 18 (3) ◽

pp. 925-934 ◽

Cited By ~ 5

Author(s):

Meghana Charde ◽

Sourabh Bhati ◽

Ayushman Kheterpal ◽

Rajiv Gupta

Keyword(s):

Energy Consumption ◽

Air Temperature ◽

Indoor Air ◽

Energy Efficient ◽

Building Envelope ◽

Combined Effect ◽

Cavity Wall ◽

Outdoor Air ◽

Reduce Energy Consumption ◽

Energy Efficient Building

Energy efficient building technologies can reduce energy consumption in buildings. In present paper effect of designed static sunshade, brick cavity wall with brick projections and their combined effect on indoor air temperature has been analyzed by constructing three test rooms each of habitable dimensions (3.0 m ? 4.0 m ? 3.0 m) and studying hourly temperatures on typical days for one month in summer and winter each. The three rooms have also been simulated using a software and the results have been compared with the experimental results. Designed static sunshade increased indoor air temperature in winter while proposed brick cavity wall with brick projections lowered it in summer. Combined effect of building elements lowered indoor air temperature in summer and increased it in winter as compared to outdoor air temperature. It is thus useful for energy conservation in buildings in composite climate.

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Development of Thermal Comfort-Based Controller and Potential Reduction of the Cooling Energy Consumption of a Residential Building in Kuwait

Energies ◽

10.3390/en12173348 ◽

2019 ◽

Vol 12 (17) ◽

pp. 3348 ◽

Cited By ~ 2

Author(s):

Jaesung Park ◽

Taeyeon Kim ◽

Chul-sung Lee

Keyword(s):

Energy Consumption ◽

Thermal Comfort ◽

Indoor Air ◽

Residential Buildings ◽

Electric Energy ◽

Residential Building ◽

Influential Factor ◽

Electric Energy Consumption ◽

Residential Electricity ◽

The Government

In Kuwait, where the government subsidizes approximately 95% of residential electricity bills, most of the country’s energy consumption is for residential use. In particular, air-conditioning (AC) systems for cooling, which are used throughout the year, are responsible for residential electric energy consumption. This study aimed to reduce the amount of energy consumed for cooling purposes by developing a thermal comfort-based controller. Our study commenced by using a simulation model to investigate the possibility of energy reduction when using the predicted mean vote (PMV) for optimal control. The result showed that control optimization would enable the cooling energy consumption to be reduced by 33.5%. The influence of six variables on cooling energy consumption was then analyzed to develop a thermal comfort-based controller. The analysis results showed that the indoor air temperature was the most influential factor, followed by the mean radiant temperature, the metabolic rate, and indoor air velocity. The thermal comfort-based controller-version 1 (TCC-V1) was developed based on the analysis results and experimentally evaluated to determine the extent to which the use of the controller would affect the energy consumed for cooling. The experiments showed that the implementation of TCC-V1 control made it possible to reduce the electric energy consumption by 39.5% on a summer representative day. The results of this study indicate that it is possible to improve indoor thermal comfort while saving energy by using the thermal comfort-based controller in residential buildings in Kuwait.

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A review on thermal comfort, indoor air quality and energy consumption in temples

Journal of Building Engineering ◽

10.1016/j.jobe.2020.102013 ◽

2020 ◽

pp. 102013

Author(s):

Ahmet Yüksel ◽

Müslüm Arıcı ◽

Michal Krajčík ◽

Mihriban Civan ◽

Hasan Karabay

Keyword(s):

Energy Consumption ◽

Air Quality ◽

Thermal Comfort ◽

Indoor Air Quality ◽

Indoor Air

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Assessment of thermal comfort in lecture room by chosen calculation methods

E3S Web of Conferences ◽

10.1051/e3sconf/20184400186 ◽

2018 ◽

Vol 44 ◽

pp. 00186

Author(s):

Małgorzata Wesołowska ◽

Marta Laska

Keyword(s):

Thermal Comfort ◽

Indoor Air ◽

Questionnaire Survey ◽

Science And Technology ◽

Hvac Systems ◽

Personal Factors ◽

Calculation Methods ◽

Complex Issue ◽

Lecture Room ◽

Comfort Parameters

The proper level of comfort conditions is one of the main goal when designing HVAC systems in buildings. It influences our self-being, our health and productivity. Thermal comfort is a complex issue and relates to indoor air parameters and personal factors. The publication presents the outcome of the research undertaken in one of the lecture room at Wroclaw University of Science and Technology, Poland. It consisted of measurements of comfort parameters, questionnaire survey and PMV and PPD calculations based on different approaches.

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A thermal environmental model for indoor air temperature prediction and energy consumption in pig building

Building and Environment ◽

10.1016/j.buildenv.2019.106238 ◽

2019 ◽

Vol 161 ◽

pp. 106238 ◽

Cited By ~ 4

Author(s):

Qiuju Xie ◽

Ji-Qin Ni ◽

Jun Bao ◽

Zhongbin Su

Keyword(s):

Energy Consumption ◽

Air Temperature ◽

Indoor Air ◽

Temperature Prediction ◽

Environmental Model ◽

Air Temperature Prediction

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User Thermal Comfort in Historic Buildings: Evaluation of the Potential of Thermal Mass, Orientation, Evaporative Cooling and Ventilation

Sustainability ◽

10.3390/su12229672 ◽

2020 ◽

Vol 12 (22) ◽

pp. 9672

Author(s):

Mamdooh Alwetaishi ◽

Ashraf Balabel ◽

Ahmed Abdelhafiz ◽

Usama Issa ◽

Ibrahim Sharaky ◽

...

Keyword(s):

Thermal Comfort ◽

High Altitude ◽

Air Temperature ◽

Thermal Performance ◽

Indoor Air ◽

Computer Modelling ◽

Evaporative Cooling ◽

Comfort Level ◽

Thermal Mass ◽

The Impact

The study investigated the level of thermal comfort in historical buildings located at a relatively high altitude in the Arabian Desert of Saudi Arabia. The study focused on the impact of the use of thermal mass and orientation on the level of thermal performance at Shubra and Boqri Palaces. Qualitative and quantitative analyses were used in this study, including a questionnaire interview with architecture experts living at the relatively high altitude of Taif city, to obtain data and information from local experts. The computer software TAS EDSL was used along with on-site equipment, such as thermal imaging cameras and data loggers, to observe the physical conditions of the building in terms of its thermal performance. The study revealed that the experts’ age and years of experience were important aspects while collecting data from them during the survey. The use of thermal mass had a slight impact on the indoor air temperature as well as the energy consumption, but it helped in providing thermal comfort. Use of ventilation can improve thermal comfort level. Evaporative cooling technique has a considerable impact on reducing indoor air temperature with 4 °C drop, improving the thermal comfort sensation level. The novelty of this work is that, it links the outcomes of qualitative results of experts with field monitoring as well as computer modelling. This can contribute as method to accurately collect data in similar case studies.

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