Simulation of Flow around a Bus with Passive Drag Reduction Attachments

In this study, a numerical simulation has been carried out for three-dimensional turbulent
flows around a bluff-based bus-like body and actual bus body. The first step ofthis study is to
verify the effectiveness of the CFD analysis. In the second step, to reduce the drag of the
actual bus model, parameter studies are performed with attention to effective utilization ofthe
rear-spoiler equipped at the roof-end of upper body. . The study is being conducted to get
clear view on how the aerodynamics changes when attaching attachments (spoiler) to reduce
the aerodynamic drag for the buses. The effect of a rear-spoiler attached at the rear end of the
bus body will be investigated.
At the early stage, it is crucialto seek for relevant information regarding the project. Previous
experiments report, journals, books and all supporting information will be reviewed for the
mean of having clear view on this topic. In the design stage, calculations, modeling, and
experiments will takes place. Simulation with computational fluid dynamics (CFD) software
will produce initial data before experiments conducted. Similarity between model and
prototype must be obtained as it is very importantto maintainthe accuracy of the data gained
from experiments.
Few series of experiments conducted in regards of a different shape of attachments. The drag
force primary data as minimizing it result in increasing the aerodynamic performance for
buses. All the results will be interpreted and discussed.
Towards the end of this semester the models of bus with passive drag reduction attachments
finalized. Final reports and presentations conducted as the research completed. All the
objectives are expected to be met during the project.
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