Experimental Investigation of Aerodynamic Interactions of Vehicles in Close Folowing and Passing Situations

Gümüşlüol, Ünsal
In this Thesis study, aerodynamic interactions of vehicle models in close following and passing situations were investigated expeimentally. Effect of the inter-vehicle spacing and lateral distance on drag coefficients of two close-following vehicles were observed. Two different types of vehicle models were used in order to investigate the shape effect on aerodynamic vehicle interactions. Drag froces and surface pressures of the models at each situation were measured. Two different blockage correction methods on the basis of drag coefficient results were applied. Linear increments of drag coefficients were observed on leading and trailing MIRA models. Beacuse of their blunter shapes and sharp edges, the leading and trailing Ahmed Body models feel the presence of aerodynamic interactions substantially. The most important reduction in drag force occurs at the least vehicle spacing for both vehicle types. In the passing situations, it was observed that drag coefficients of MIRA models did not change considerably. However, big amount of changes were observed at all positions for Ahmed Body. Maximum values of drag coefficients were reached when the models were at side by side position for both vehicle types. In conclusion, it is possible to obtain more drag reductions with more numbers of vehicles in close-following. the lower drag coefficients in close-following operations caues to increase fuel savings and to reduce air pollution.


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Citation Formats
Ü. Gümüşlüol, “Experimental Investigation of Aerodynamic Interactions of Vehicles in Close Folowing and Passing Situations,” M.S. - Master of Science, Middle East Technical University, 2006.