• ISSN 0258-2724
  • CN 51-1277/U
  • EI Compendex
  • Scopus
  • Indexed by Core Journals of China, Chinese S&T Journal Citation Reports
  • Chinese S&T Journal Citation Reports
  • Chinese Science Citation Database
Volume 56 Issue 1
Jan.  2021
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Article Contents
ZHUANG Jiawei, DIAO Yongfa, ZHANG Li’an, SHEN Henggen. Evolution Characteristics of Indoor Pollutant Concentration in Buoyancy-Driven Natural Ventilation[J]. Journal of Southwest Jiaotong University, 2021, 56(1): 47-55. doi: 10.3969/j.issn.0258-2724.20190582
Citation: ZHUANG Jiawei, DIAO Yongfa, ZHANG Li’an, SHEN Henggen. Evolution Characteristics of Indoor Pollutant Concentration in Buoyancy-Driven Natural Ventilation[J]. Journal of Southwest Jiaotong University, 2021, 56(1): 47-55. doi: 10.3969/j.issn.0258-2724.20190582

Evolution Characteristics of Indoor Pollutant Concentration in Buoyancy-Driven Natural Ventilation

doi: 10.3969/j.issn.0258-2724.20190582
  • Received Date: 24 Jun 2019
  • Rev Recd Date: 26 Oct 2019
  • Available Online: 20 Nov 2019
  • Publish Date: 01 Feb 2021
  • Evolution of pollutant concentration at different heights was analyzed to explore the evolution rule of indoor gaseous pollutants during a period from buoyacy-driven natural ventilation to steady state. Firstly, according to the non-uniform three-layer model used to examine the transient flows driven by buoyancy force, two theoretical models that correspond to homogeneous mix and pure displacement were developed for the different mixing characteristics of the inoor lower-layer pollutants. Then, the fourth-order Runge-Kutta method was adopted to find a iterative solution, and the height and concentration variation characteristics of the indoor pollutants during the ventilation process were obtained. Finally, the effects of the effective ventilation area and buoyancy combination coefficient on pollutant concentration was discussed. The results show that, the thermal stratification interface with zero vertical velocity greatly differs from the fresh air layer interface, and the height difference between thermal stratification interfaces will have a larger peak value and a shorter time to reach steady state when the dimensionless effective ventilation area becomes larger. The greater buoyancy combination coefficient is, the greater the height difference between thermal stratification interfaces at any time is, which becomes more obvious with the increase of the dimensionless effective ventilation area. The mixing characteristics of lower-layer pollutants affect the stratification and time evolution, but do not change the concentration distribution in steady state, and the upper layer has the highest pollutant concentration for both models. For the pure-displacement model, the pollutant concentration of the original layer decreases until it reaches stability, and the lower-layer pollutant concentration remains constant, while that of the upper layer increases sharply in the initial stage before decaying. Meanwhile, the average pollutant concentration of the upper and lower layers both slowly decay to a stable value for the homogeneous mix model. Furthermore, a larger dimensionless effective ventilation area can result in a faster decay of the dimensionless pollutant on the pollutant concentration can be almost ignored.

     

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  • WANG J, ZHANG T, WANG S, et al. Gaseous pollutant transmission through windows between vertical floors in a multistory building with natural ventilation[J]. Energy and Buildings, 2017, 153: 325-340. doi: 10.1016/j.enbuild.2017.08.025
    陶天吟. 热压自然通风房间气流特性及热舒适性研究[D]. 扬州: 扬州大学, 2015.
    LINDEN P F, LANE-SERFF G F, SMEED D A. Emptying filling boxes:the fluid mechanics of natural ventilation[J]. Journal of Fluid Mechanics, 1990, 212: 309-335. doi: 10.1017/S0022112090001987
    HUNT G R, KAYE N B. Pollutant flushing with natural displacement ventilation[J]. Building and Environment, 2006, 41(9): 1190-1197. doi: 10.1016/j.buildenv.2005.04.022
    KAYE N B, HUNT G R. Time-dependent flows in an emptying filling box[J]. Journal of Fluid Mechanics, 2004, 520: 135-156. doi: 10.1017/S0022112004001156
    YANG X, KANG Y, ZHONG K. Theoretical predictions of transient natural displacement ventilation[J]. Building Simulation, 2013, 6(2): 165-171. doi: 10.1007/s12273-013-0098-7
    ZHUANG J, JIANG Q, DIAO Y. Non-uniform three-layer models to predict transient flows in buoyancy-driven natural ventilation with a localized heat source[J]. Science and Technology for the Built Environment, 2019, 25: 643-655. doi: 10.1080/23744731.2018.1556054
    杨秀峰,钟珂,亢燕铭. 热压自然通风房间的瞬态污染状况分析[J]. 东华大学学报(自然科学版),2012,38(6): 750-757. doi: 10.3969/j.issn.1671-0444.2012.06.021

    YANG Xiufeng, ZHONG Ke, KANG Yanming. Analysis on transient air pollution in buoyancy-induced naturally ventilated enclosures[J]. Journal of Donghua University (Natural Science), 2012, 38(6): 750-757. doi: 10.3969/j.issn.1671-0444.2012.06.021
    MORTON B R, TAYLOR G, TRUNER J S. Turbulent gravitational convection from maintained and instantaneous sources[J]. Proceedings of the Royal Society A:Mathematical Physical and Engineering Sciences, 1956, 234(1196): 1-23.
    FAURE X, ROUX N L. Thermal stratification produced by plumes and jets in encloused spaces[J]. Building and Environment, 2012, 50: 221-230. doi: 10.1016/j.buildenv.2011.11.007
    LI Y. Buoyancy-driven natural ventilation in a thermally stratified one-zone building[J]. Building and Environment, 2000, 35(3): 207-214. doi: 10.1016/S0360-1323(99)00012-8
    KAYE N B, HUNT G R. Heat source modelling and natural ventilation efficiency[J]. Building and Environment, 2007, 42(4): 1624-1631. doi: 10.1016/j.buildenv.2006.02.005
    BOLSTER D T, LINDEN P F. Contaminants in ventilated filling boxes[J]. Journal of Fluid Mechanics, 2007, 591: 97-116. doi: 10.1017/S0022112007007732
    YANG X, WANG G, ZHONG K, et al. Transient pollutant flushing of buoyancy-driven natural ventilation[J]. Building Simulation, 2012, 5(2): 147-155. doi: 10.1007/s12273-012-0077-4
    KAYE N B, JIANG Y, COOK M J. Numerical simulation of transient flow development in a naturally ventilated room[J]. Building and Environment, 2009, 44(5): 889-897. doi: 10.1016/j.buildenv.2008.06.016
    YANG X, ZHONG K, KANG Y, et al. Numerical investigation on the airflow characteristics and thermal comfort in buoyancy-driven natural ventilation rooms[J]. Energy and Buildings, 2015, 109: 255-266. doi: 10.1016/j.enbuild.2015.09.071
    SEIFERT J, LI Y, AXLEY J, et al. Calculation of wind-driven cross ventilation in buildings with large openings[J]. Journal of Wind Engineering and Industrial Aerodynamics, 2006, 94(12): 925-947. doi: 10.1016/j.jweia.2006.04.002
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