Ventilation rate requirements for enclosed motor vehicle facilities

The ventilation of enclosed facilities with motor vehicle emission is the main subject of this thesis. Because the design of optimal and efficient ventilation of such facilities translates into savings of fan energy and adequate indoor air quality, a research program is carried to (1) review current national and international ventilation standards, (2) conduct field measurements of contaminant concentration in several parking garages distributed nation-wide, (3) develop transport models which duplicate actual ventilation systems in parking garages, and (4) assess the efficiency of these systems in removing contaminants with minimum energy consumption.; This work provides an overview of the current standards and regulations specific to the ventilation requirements in enclosed parking facilities in the US and other countries. A complete discussion of the emission rates of motor vehicle pollutants and their health effects is presented. In particular, typical emission rates for different vehicle and fuel types are presented to highlight the effect of various parameters on the ventilation rate requirements for parking garages. In addition, this work provides a brief description of some of the common ventilation problems reported in the literature for enclosed parking garages.; A field measurement program to determine the ventilation requirements and the contaminant levels in existing enclosed parking garages has been conducted. The measurements are conducted in seven parking garages with different sizes, traffic flow patterns, vehicle types, and locations. In particular, the study compares the actual ventilation rates measured using the tracer gas technique with the ventilation requirements set by the ASHRAE standard 62-1989. In addition, the experimental program evaluates the effectiveness of existing ventilation systems in maintaining acceptable contaminant level within enclosed parking garages.; A new design approach is proposed in this work to determine the ventilation requirements for enclosed parking garages. The design approach accounts for various factors that affect indoor air quality within a parking facility including the average CO emission rate, the average travel time, the number of cars, and the acceptable CO level within the parking garage. This work describes first the results of a parametric analysis based on which the design method is developed. Then, the design method is presented to explain how the ventilation flow rate can be determined for any enclosed parking facility.; For prediction of contaminant concentration, a simplified model is used to predict CO concentration within the parking facilities, using cfm, and generation rate. Also, using computational fluid dynamics models with integration of control modules, an accurate prediction is made for a real case, in steady and transient modes. The CFD approach also allows the prediction of best fan location and improvement of ventilation effectiveness. Finally, some suggestions are proposed to save fan energy for ventilating parking garages using demand ventilation control strategies.