In recent years, split floor-standing room air conditioners have been widely used in civil and office buildings because of their high cooling capacity and easy installation, and the air draft sensation has attracted more and more attention. In this study, a target air supply evaluation index for regional thermal comfort evaluation in the work area, the air velocity target value, is proposed. A computational fluid dynamics model for common office is established, and a total of 204 working conditions are numerically simulated for each combination of different positions, different rotation angles, and different air supply velocities (1 m/s, 2 m/s and 3 m/s) of air conditioners in the room. The influence of the rotation angle of the air conditioner on the indoor air distribution was studied, and the distribution of the indoor velocity flow field at different positions was analyzed. The air-conditioning rotation angle that makes the velocity target value of the five preset planes in the room smaller under different conditions is summarized as the recommended rotation angle. The numerical simulation results were verified by experimental means and found to be consistent with the measured results. This study can provide theoretical guidance and reference for the placement of indoor air conditioning units for users in real life.
2020 China Building Energy Consumption Research. 2020.
Hu S, Yan D, Qian M. Using bottom-up model to analyze cooling energy consumption in China’s urban residential building. Energy Build 2019; 202: 109352. https://doi.org/10.1016/J.ENBUILD.2019.109352.
He Y, Li N, Peng J, Zhang W, Li Y. Field study on adaptive comfort in air conditioned dormitories of university with hot-humid climate in summer. Energy Build 2016; 119: 1–12. https://doi.org/10.1016/J.ENBUILD.2016.03.020.
Buonocore C, de Vecchi R, Scalco V, Lamberts R. Influence of recent and long-term exposure to air-conditioned environments on thermal perception in naturally-ventilated classrooms. Build Environ 2019; 156: 233–42. https://doi.org/10.1016/J.BUILDENV.2019.04.009.
Chao CYH, Wan MP. Airflow and air temperature distribution in the occupied region of an underfloor ventilation system. Build Environ 2004; 39: 749–62. https://doi.org/10.1016/J.BUILDENV.2004.01.010.
National Bureau of Statistics of China. China Statistical Yearbook 2021. Beijing: China Statistics Press; 2021.
Wang Y, Kuckelkorn J, Zhao FY, Liu D, Kirschbaum A, Zhang JL. Evaluation on classroom thermal comfort and energy performance of passive school building by optimizing HVAC control systems. Build Environ 2015; 89: 86–106. https://doi.org/10.1016/J.BUILDENV.2015.02.023.
Huang SY, Zhao F, Li G. Numerical simulation study on the thermal environment of an air-conditioned in summer based on Airpak. Journal of Hunan University of Science and Technology 2011; 26: 11–7.
Liu W. Study on Objective Evaluation Index of Human Thermal Comfort. Doctoral dissertation, PhD Thesis. Shanghai Jiao Tong University, 2007.
Liu W, Lian Z, Yao Y. Optimization on indoor air diffusion of floor-standing type room air-conditioners. Energy Build 2008; 40: 59–70. https://doi.org/10.1016/J.ENBUILD.2007.01.010.
Yin G. The indoor thermal comfort research of the air conditioning mode in large space. University of South China, 2009.
Zhang Z, Gao R, Liu Y, Liu M, Wang Y, Zhu W, et al. Smart air supply terminal for floor-standing room air conditioners based on the identification of human positions. Build Environ 2021; 202: 108041. https://doi.org/10.1016/J.BUILDENV.2021.108041.
Li Y. Study on indoor airflow organization and thermal comfort of air conditioning system in the office building. North China University of Technology, 2017.
Gao CF, Lee WL. Optimized design of floor-based air-conditioners for residential use. Build Environ 2009; 44: 2080–8. https://doi.org/10.1016/J.BUILDENV.2009.02.011.
Xin S, Xu H, Li S, Wang W, Guo J, Yang W. Efficiency evaluation of a floor standing air conditioner with different installation positions and air supply parameters applied to a large laboratory. Journal of Building Engineering 2020; 32: 101701. https://doi.org/10.1016/J.JOBE.2020.101701.
Ma R. Displacement ventilation effectiveness and evaluation of the micro thermal environment. Journal of HVAC 1997; 27: 1–6.
Li X, Zhao B. Numerical simulation of indoor airflow. Mechanical Industry Press; 2009.
Fanger PO. Thermal comfort. Analysis and applications in environmental engineering. Copenhagen: Danish Technical Press; 1970.
Wang X, Liu T, Lee WL. Using revised ADPIs to identify an optimum positioning for installation of reversible room air-conditioners in bedroom for maximum thermal comfort. Build Environ 2021; 188: 107333. https://doi.org/10.1016/J.BUILDENV.2020.107333.
Gao R, Wang C, Li A, Yu S, Deng B. A novel targeted personalized ventilation system based on the shooting concept. Build Environ 2018; 135: 269–79. https://doi.org/10.1016/J.BUILDENV.2018.03.016.
Gao R, Zhang H, Li A, Wen S, Du W, Deng B. A new evaluation indicator of air distribution in buildings. Sustain Cities Soc 2020; 53: 101836. https://doi.org/10.1016/J.SCS.2019.101836.
Chen Q. Comparison of different k-ε models for indoor airflow computations. Numerical Heat Transfer, Part B: Fundamentals 1995; 28: 353–69. https://doi.org/10.1080/10407799508928838.
Ye X, Zhu H, Kang Y, Zhong K. Heating energy consumption of impinging jet ventilation and mixing ventilation in large-height spaces: A comparison study. Energy Build 2016; 130: 697–708. https://doi.org/10.1016/J.ENBUILD.2016.08.055.
Rouaud O, Havet M. Computation of the airflow in a pilot scale clean room using K-ε turbulence models. International Journal of Refrigeration 2002; 25: 351–61. https://doi.org/10.1016/S0140-7007(01)00014-7.
ASHRAE. ANSI/ASHRAE Standard 55-2017: Thermal Environmental Conditions for Human Occupancy. ASHRAE Inc 2017; 2017.
Fanger PO, Melikov AK, Hanzawa H, Ring J. Air turbulence and sensation of draught. Energy Build 1988; 12: 21–39. https://doi.org/10.1016/0378-7788(88)90053-9.
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