Comparative study on energy consumption and indoor thermal environment between convective air-conditioning terminals and radiant ceiling terminals

2022 ◽  
Vol 209 ◽  
pp. 108661
Author(s):  
Wei Liao ◽  
Jinqing Peng ◽  
Yimo Luo ◽  
Yingdong He ◽  
Nianping Li ◽  
...  
2013 ◽  
Vol 316-317 ◽  
pp. 1128-1132
Author(s):  
Ya Zhou Jing ◽  
Guo Jun Zhao ◽  
Hai Shan Li ◽  
Yan Gao

In this paper, it reveals that the ventilation using patterns can do much to the energy consumption for air-conditioning. In the simulation, it models the person behavior with their action for regulating indoor thermal environment by opening the window for natural ventilation, and compares the influence by ventilation in different patterns to the air conditioning energy consumption. The results show that in the pattern priority for using the natural wind it is helpful for reducing the energy consumption.


2016 ◽  
Vol 858 ◽  
pp. 234-240
Author(s):  
Yue Fu ◽  
Wei Ju Yang

A shading roof can be an effective strategy to decrease the air-conditioning energy consumption as well as to improve the thermal environment inside a house in the place that is hot in summer and cold in winter. In Suzhou, a city in such place, traditional dwellings were constructed with shading roof eaves that have different sizes, allowing them adaptive to local climate. These eaves are worthy of being studied and improved. This study presents a summary of the sizes of the shading roof eaves of traditional Suzhou dwellings. The southward eave that has the greatest effect on indoor thermal environment is taken as the object of the current study, and a traditional Suzhou dwelling is selected as our case for the current study. Several comparative models are built, in which, the southward length of the roof eave is increased by 0.2m, from 0m to 2m. The effects of the length on both heating and cooling energy consumption are simulated by using the software Energyplus. As shown in the quantitative analysis of the simulation results, the structure is energy-efficient when the length is less than 0.6m, and the annual energy consumption reaches its minimum when the length is 0.4m.


2020 ◽  
pp. 014459872096921
Author(s):  
Yanru Li ◽  
Enshen Long ◽  
Lili Zhang ◽  
Xiangyu Dong ◽  
Suo Wang

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.


2019 ◽  
Vol 41 (5) ◽  
pp. 561-585 ◽  
Author(s):  
Fangliang Zhong ◽  
John K Calautit ◽  
Ben R Hughes

After winning the bid of the FIFA’s World Cup 2022, Qatar is facing the greatest challenges in terms of minimizing substantial energy consumptions for air-conditioning of stadiums and maintaining aero-thermal comfort for both players and spectators inside stadiums. This paper presents the results of temperature distributions and wind environment of the original stadium under the hot-humid climate and improvements on them for optimized scenarios of cooling jets. A combined computational fluid dynamics and building energy simulation approach was used to analyse the cooling performance and energy consumption per match of cooling air jets for 10 scenarios with different supply velocities, supply temperatures and locations of jets. The optimal scenario is to employ vertical jets above the upper tiers at supply temperature of 20°C and velocities of 2–12 m/s, integrated with horizontal jets of the same temperature at the lower tiers with 4 m/s and around the pitch with 7 m/s. This scenario can maintain the spectator tiers at an average temperature of 22°C and reduce the maximum predicted percentage of dissatisfied of thermal comfort from the original 100% to 63% for the pitch and 19% for the tiers, respectively. In terms of the energy consumption for the air-conditioning system per match, compared with one of the 2010 South Africa World Cup stadiums Royal Bafokeng stadium which consumed approximately 22.8 MWh energy for air-conditioning in winter (highest outdoor temperature 24.4°C), the maximum energy consumption of the optimal scenario in November (highest outdoor temperature 34.2°C) can reach 108 MWh. In addition, the spectator zones with scenario 8 have the potential to be resilient to the seasonal change of outdoor temperature if slight modifications of the supply velocities and precise temperature control on the spectator zones are applied. Moreover, the configurations presented in this paper can be used as a foundation of jets arrangement for future stadium retrofits in the hot climates. Practical application: This study assesses the aero-thermal conditions of a case study stadium under the hot climate of Qatar and explores the potential of applying cooling jets with different supply velocities, supply temperatures and their locations on the enhancement of both thermal and wind environment of spectator tiers and pitch. The assessment of the original stadium indicates that the ascending curved roof structure impedes the fresh air entering into the stadium and results in an asymmetric temperature distribution on the spectator tiers. The optimized design suggests a combination of vertical jets under the roof and both three arrays of horizontal jets at lower tiers and around pitch for future stadium optimizations in hot climates. It also recommends enhancing the thermal conditions on the pitch by optimizing the velocity of horizontal jets around the pitch. Moreover, the future design of the exact stadiums to be resilient to the seasonal changing outdoor temperature can be implemented based on scenario 8.


2020 ◽  
Vol 12 (16) ◽  
pp. 6637
Author(s):  
Jiayu Li ◽  
Bohong Zheng ◽  
Xiao Chen ◽  
Yihua Zhou ◽  
Jifa Rao ◽  
...  

As the window-to-wall ratio, a microclimatic factor in residential districts, regulates the indoor thermal environment and implicates the energy consumption, this research was aimed at interpreting the microclimate effects of the window-to-wall ratio on the indoor thermal environment of the non-Hvac building located in the block from the view of a full year. Urban built parameters and building material parameters applied in Chenzhou were investigated, with the ENVI-met model serving as the analytical tool calculating the meteorological data recorded in the local national meteorological station. The thermal perception criterion of Chenzhou citizens was investigated, and thermal isotherms were employed to interpret the thermal perception distribution throughout the year. Analytical results revealed that the annual indoor thermal environment would deteriorate along with the growth of the window-to-wall ratio in Chenzhou, with the very hot thermal perception environment covering the months from March to October once the window-to-wall ratio outnumbered 60.00%. Furthermore, the hot and very hot thermal perception environments originated in the ranges of 0.00% to 20.00% and that of 20.00% to 40.00%, respectively. Furthermore, if the window-to-wall ratios (WWRs) outnumbered 40%, their effects on the indoor thermal perception environment would gradually decrease and be powerless once that exceeded 80%.


2019 ◽  
Vol 30 (1) ◽  
pp. 99-113 ◽  
Author(s):  
Haofu Chen ◽  
Zhuangbo Feng ◽  
Shi-Jie Cao

Rational and scientific design of indoor air conditioning is essential. In the design of Heating, Ventilating and Air Conditioning system, air-supply speed (ventilation rate) and air-supply temperature are the two most important parameters. In the current study, numerical simulations and experimental measurements were adopted to investigate the influences of ventilation mode, air-supply velocity and air-supply temperature on indoor thermal comfort as well as building energy consumption in summer. Different ventilation modes (up supply and down exit, ceiling supply and ceiling exit) were considered in modelling. Based on the simulation and experimental results, dimensionless index [Formula: see text] is proposed, which represents the ratio of buoyancy weighting force to inertial force. This index can be used as a pre-evaluation index of indoor thermal comfort in preliminary design of air conditioning. It is an indicator to judge the working conditions in cooling-ventilated rooms. When [Formula: see text], the settlement and diffusion effects of indoor airflow reach a good level, which means that the parameter setting could provide a comfortable indoor thermal environment. The dimensionless number [Formula: see text] is a theoretically based tool in the pre-evaluation of indoor thermal environment, providing guidance for setting of ventilation design parameters.


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