Flow drags across three minibus car models arranged in tandem in four configurations

Abstract

Abstract The purpose of this study was to investigate the drag coefficient of flow on three tandem minibuses in four configurations and to determine the optimum drag coefficient across the three cars. Flow drags measurements have been conducted on a wind tunnel by force balance measurement. The minibus car models with a 1:40 ratio to the originals were constructed from iron material with a thickness of 1 mm. The three minibus cars are arranged in four configuration models where car 1 and car 2 are arranged in series while car 3 position changeable according to the configuration. Each configuration model was treated with 6 changes in the distance of the car to 3, while the distance between car 1 and 2 was constant, with similar 7 levels of treatment of velocities ranging from 8 m/s to 20 m/s. Results show a similar drag coefficient (Cd) pattern in all configuration models, where smaller Cd related to greater velocities and smaller distances of the three cars. Furthermore, at a similar Re = 49,608, the smallest Cd was obtained in model III (Cd = 0.78), and followed by model II (Cd = 0.80), model IV (Cd = 0.81) and model I (Cd = 0.84).