Numerical investigation of wind-driven natural ventilation performance in a multi-storey hospital by coupling indoor and outdoor airflow

This study employed two ventilation indexes: local mean age of air and air change rate per hour, to investigate wind-induced natural ventilation of 260 wards of a multi-storey hospital building in suburb of Guangzhou using computational fluid dynamics simulations. Using the surface-grid extrusion technique, high-quality hexahedral grid cells were generated for the coupled outdoor and indoor airflow field. Turbulence was solved by the renormalisation group k-ɛ model validated against experimental data with grid independence studies. Homogeneous tracer gas emission was adopted to predict room age of air. The air change rate of cross ventilation and single-sided ventilation can reach 30–160 h−1 and 0.5–7 h−1, respectively. Due to different locations of room openings on the balconies, natural ventilation of a room can be greatly better than its neighbouring room. The wind-induced cross ventilation highly depends on the distance from the room opening to the stagnation point and on the resulting pressure distribution on the target building surface. Furthermore, it is significantly influenced by the upstream buildings, the bent shape of the target building, and the prevailing wind directions. The coupled computational fluid dynamics methodologies with integrated ventilation indexes are useful for assessing the natural ventilation performance in other complex built environments.

[1]  Yi Wang,et al.  Ventilation system type, classroom environmental quality and pupils' perceptions and symptoms , 2014 .

[2]  M. Sandberg,et al.  Building Ventilation: Theory and Measurement , 1996 .

[3]  Bje Bert Blocken,et al.  On the effect of wind direction and urban surroundings on natural ventilation of a large semi-enclosed stadium , 2010 .

[4]  D. Grawe,et al.  BEST PRACTICE GUIDELINE FOR THE CFD SIMULATION OF FLOWS IN THE URBAN ENVIRONMENT , 2007 .

[5]  G Murphy,et al.  Airborne spread of measles in a suburban elementary school. , 1978, American journal of epidemiology.

[6]  W. H. Ching,et al.  Natural ventilation for reducing airborne infection in hospitals , 2009, Building and Environment.

[7]  Chia-Jung Hsu Numerical Heat Transfer and Fluid Flow , 1981 .

[8]  T. Stathopoulos,et al.  CFD simulation of the atmospheric boundary layer: wall function problems , 2007 .

[9]  Kevin J. Lomas,et al.  Performance of hospital spaces in summer: A case study of a ‘Nucleus’-type hospital in the UK Midlands , 2013 .

[10]  Maria K. Koukou,et al.  Natural cross-ventilation in buildings: Building-scale experiments, numerical simulation and thermal comfort evaluation , 2008 .

[11]  Mats Sandberg,et al.  Age of air and air exchange efficiency in idealized city models , 2009 .

[12]  Atila Novoselac,et al.  Cross ventilation with small openings: Measurements in a multi-zone test building , 2012 .

[13]  Bje Bert Blocken,et al.  CFD simulation of cross-ventilation for a generic isolated building : impact of computational parameters , 2012 .

[14]  Da-Wen Sun,et al.  Optimising the ventilation configuration of naturally ventilated livestock buildings for improved indoor environmental homogeneity , 2010 .

[15]  William H. Snyder,et al.  Similarity criteria for the application of fluid models to the study of air pollution meteorology , 1972 .

[16]  Gabriel M. Leung,et al.  Ventilation Control of Indoor Transmission of Airborne Diseases in an Urban Community , 2009 .

[17]  Bje Bert Blocken,et al.  Overview of pressure coefficient data in building energy simulation and airflow network programs , 2009 .

[18]  A. R. Escombe,et al.  Natural Ventilation for the Prevention of Airborne Contagion , 2007, PLoS medicine.

[19]  Qingyan Chen,et al.  Ventilation performance prediction for buildings: A method overview and recent applications , 2009 .

[20]  Nikos Nikolopoulos,et al.  Numerical study of a naturally cross-ventilated building , 2010 .

[21]  Tomoyuki Chikamoto,et al.  Evaluation of ventilation performance of monitor roof in residential area based on simplified estimation and CFD analysis , 2013 .

[22]  Yuguo Li,et al.  Natural ventilation induced by combined wind and thermal forces , 2001 .

[23]  Peter Richards,et al.  Pressures on a cubic building—Part 1: Full-scale results , 2012 .

[24]  C. A. Gilkeson,et al.  Measurement of ventilation and airborne infection risk in large naturally ventilated hospital wards , 2013 .

[25]  Chun-Ho Liu,et al.  CFD simulations of natural ventilation behaviour in high-rise buildings in regular and staggered arr , 2011 .

[26]  Gennady Ziskind,et al.  Effect of wind direction on greenhouse ventilation rate, airflow patterns and temperature distributions , 2008 .

[27]  Donal Finn,et al.  Sensitivity of air change rates in a naturally ventilated atrium space subject to variations in external wind speed and direction , 2008 .

[28]  Liping Wang,et al.  Coupled simulations for naturally ventilated residential buildings , 2008 .

[29]  Tze Wai Wong,et al.  Evidence of airborne transmission of the severe acute respiratory syndrome virus. , 2004, The New England journal of medicine.

[30]  Z T Ai,et al.  Numerical investigation of wind-induced airflow and interunit dispersion characteristics in multistory residential buildings. , 2013, Indoor air.

[31]  Mats Sandberg,et al.  Stream Tube based Analysis of Problems in Prediction of Cross-Ventilation Rate , 2009 .

[32]  Angui Li,et al.  Measurement of temperature, relative humidity, concentration distribution and flow field in four typical Chinese commercial kitchens , 2012 .

[33]  Nikos Nikolopoulos,et al.  Characterization and prediction of the volume flow rate aerating a cross ventilated building by means of experimental techniques and numerical approaches , 2011 .

[34]  Cheuk Ming Mak,et al.  Determination of single-sided ventilation rates in multistory buildings: Evaluation of methods , 2014 .

[35]  Bert Blocken,et al.  CFD simulation for pedestrian wind comfort and wind safety in urban areas: General decision framework and case study for the Eindhoven University campus , 2012, Environ. Model. Softw..

[36]  Qingyan Chen,et al.  Natural Ventilation in Buildings: Measurement in a Wind Tunnel and Numerical Simulation with Large Eddy Simulation , 2003 .

[37]  Konstantinos-Stefanos Nikas,et al.  Experimental and numerical investigation of the tracer gas methodology in the case of a naturally cross-ventilated building , 2012 .

[38]  John S. Irwin,et al.  A theoretical variation of the wind profile power-law exponent as a function of surface roughness and stability , 1979 .

[39]  P. Heiselberg,et al.  The airborne transmission of infection between flats in high-rise residential buildings: Tracer gas simulation , 2007, Building and Environment.

[40]  Anh Tuan Nguyen,et al.  The effect of ceiling configurations on indoor air motion and ventilation flow rates , 2011 .

[41]  Ryuichiro Yoshie,et al.  CFD modelling of unsteady cross ventilation flows using LES , 2008 .

[42]  Mats Sandberg,et al.  Experimental investigation and CFD analysis of cross-ventilated flow through single room detached house model , 2010 .

[43]  Ch. Nikita-Martzopoulou,et al.  Analysis of airflow through experimental rural buildings : Sensitivity to turbulence models , 2007 .

[44]  Bje Bert Blocken,et al.  CFD evaluation of natural ventilation of indoor environments by the concentration decay method: CO2 gas dispersion from a semi-enclosed stadium , 2013 .

[45]  R. Hobday,et al.  Roles of sunlight and natural ventilation for controlling infection: historical and current perspectives , 2013, Journal of Hospital Infection.

[46]  An-Shik Yang,et al.  Myth of ecological architecture designs: Comparison between design concept and computational analysis results of natural-ventilation for Tjibaou Cultural Center in New Caledonia , 2011 .

[47]  Thierry Boulard,et al.  Optimisation of Greenhouse Insect Screening with Computational Fluid Dynamics , 2006 .

[48]  Andrew D.F. Price,et al.  Performance evaluation of natural ventilation strategies for hospital wards A case study of Great Ormond Street Hospital , 2012 .

[49]  Bert Blocken,et al.  Coupled urban wind flow and indoor natural ventilation modelling on a high-resolution grid: A case study for the Amsterdam ArenA stadium , 2010, Environ. Model. Softw..

[50]  A. Mochida,et al.  Methods for controlling airflow in and around a building under cross-ventilation to improve indoor thermal comfort , 2005 .

[51]  Yoshihide Tominaga,et al.  AIJ guidelines for practical applications of CFD to pedestrian wind environment around buildings , 2008 .

[52]  P V Nielsen,et al.  Role of ventilation in airborne transmission of infectious agents in the built environment - a multidisciplinary systematic review. , 2007, Indoor air.

[53]  Andreas K. Athienitis,et al.  Airflow assessment in cross-ventilated buildings with operable façade elements , 2011 .

[54]  Da-Wen Sun,et al.  Assessing the ventilation effectiveness of naturally ventilated livestock buildings under wind dominated conditions using computational fluid dynamics , 2009 .

[55]  Carol C. Menassa,et al.  Optimizing hybrid ventilation in public spaces of complex buildings – A case study of the Wisconsin Institutes for Discovery , 2013 .

[56]  Cheuk Ming Mak,et al.  A study of interunit dispersion around multistory buildings with single-sided ventilation under different wind directions , 2014 .

[57]  Abdullah S Ali,et al.  Impact of Artemisinin-Based Combination Therapy and Insecticide-Treated Nets on Malaria Burden in Zanzibar , 2007, PLoS medicine.

[58]  G. Evola,et al.  Computational analysis of wind driven natural ventilation in buildings , 2006 .

[59]  B. Launder,et al.  The numerical computation of turbulent flows , 1990 .

[60]  D. W. Etheridge,et al.  A simple parametric study of ventilation , 1984 .

[61]  C.-F. Gao,et al.  Evaluating the influence of openings configuration on natural ventilation performance of residential , 2011 .

[62]  Weiwei Liu,et al.  Feedback from human adaptive behavior to neutral temperature in naturally ventilated buildings: Physical and psychological paths , 2013 .

[63]  S. Patankar Numerical Heat Transfer and Fluid Flow , 2018, Lecture Notes in Mechanical Engineering.