Abstract
Large-eddy simulation (LES) was used to study the flow around a simplified tractor-trailer model. The model consists of two boxes placed in tandem. The front box represents the cab of a tractor-trailer road vehicle and the rear box represents the trailer. The LES was made at the Reynolds number of \(0.51 \times 10^6\) based on the height of the rear box and the inlet air velocity. Two variants of the model were studied, one where the leading edges on the front box are sharp and one where the edges are rounded. One small and one large gap width between the two boxes were studied for both variants. Two computational grids were used in the LES simulations and a comparison was made with available experimental force measurements. The results of the LES simulations were used to analyze the flow field around the cab and in the gap between the two boxes of the tractor-trailer model. Large vortical structures around the front box and in the gap were identified. The flow field analysis showed how these large vortical structures are responsible for the difference in the drag force for the model that arises when the leading edges on the front box are rounded and the gap width is varied.
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Acknowledgments
This project is supported financially by Trafikverket (Swedish Transport Administration). Software licenses were provided by AVL List GMBH. Computations were performed at SNIC (Swedish National Infrastructure for Computing) at the Center for Scientific Computing at Chalmers (C3SE).
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Östh, J., Krajnović, S. (2016). A LES Study of a Simplified Tractor-Trailer Model. In: Dillmann, A., Orellano, A. (eds) The Aerodynamics of Heavy Vehicles III. ECI 2010. Lecture Notes in Applied and Computational Mechanics, vol 79. Springer, Cham. https://doi.org/10.1007/978-3-319-20122-1_21
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DOI: https://doi.org/10.1007/978-3-319-20122-1_21
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