Methodology for the Evaluation of Natural Ventilation in ... - Cham

selecting boundary conditions) to enhance the performance of naturally ventilated buildings andimprove simulation methods.The organization of this thesis is as follows:Chapter 2 presents the three types of natural ventilation and building characteristics thatare often considered in the design of naturally ventilated buildings. Also presented are themethods used to assessing the performance of a naturally ventilated commercial officebuilding used as reference point for the development of the methodology.Chapter 3 describes the process and measurements taken in evaluating the reference, orprototype building, Houghton Hall. A description of the building and presentation of thedata resulting from 16 months of monitoring are presented and will be used in part tovalidate the methodology in a later chapter.Chapter 4 explains the modeling and flow visualization techniques that are currently inuse for models at a variety of scales and working fluids. An overview of the three mainmodeling techniques is presented, along with the impact of scale, fluid, and naturalventilation type under investigation. The principles of flow visualization and itsapplication to buildings is discussed, along with the selection of the technique used in thereduced-scale modeling experiments.Chapter 5 provides dimensional analysis and similitude requirements for the use of scalemodeling in simulating full-scale phenomena. The governing equations for the analysis offlow are presented and then non-dimensionalized to obtain the dimensionless parameters.The selection of which dimensionless parameters to match is discussed, along with othersimilarity requirements for reduced-scale modeling.Chapter 6 outlines the experiments conducted using the reduced-scale air model in thetest chamber. Buoyancy, wind and combined natural ventilation experiments aredescribed for several different configurations using both the physical model and thecomplimentary numerical model,. The equipment and model materials used in theconstruction and measurement of the reduced-scale air model are presented.Chapter 7 presents the data gathered from the experimental and computational models.Included in this chapter are the analyses and comparisons of the modeling techniquesused, and issues that arose while conducting the experimental and simulation work. Theresults are presented in non-dimensionalized form for comparison.Chapter 8 provides guidelines for modeling airflow in naturally ventilated buildings. Acomparison of the current techniques including the methodology developed for thisresearch, how to apply those techniques in modeling, and the limitations of eachtechnique are discussed.Chapter 9 concludes the thesis and provides suggestions for future research. A summaryand evaluation of the method developed for evaluating natural ventilation in buildingsusing a reduced-scale air model are presented. References and appendices follow Chapter 923