Numerical Study on Improvement of Hydrofoil Performance using Vortex Generators (RESEARCH NOTE)

نویسندگان

  • Arash Ashrafi Marine Engineering Department, Amirkabir University of Technology
چکیده مقاله:

In this paper the effects of rigid triangular passive vortex generators on a  hydrofoil were investigated numerically.  In the first step using the Finite Volume Method the bare hydrofoil  were modeled and the results of lift and drag coefficients were validated using experimental data. In the next step the hydrofoil armed with vortex generators was modeled and its effect on the hydrofoil performance was examined.  In the next step by introducing a source term into the momentum equation the vortex generators effect was considered. However their geometry  was completely removed. The results showed that this can significantly decrease the computational memory and calculation time. The results also revealed that the use of vortex generators can delay the stall conditions by increase the stall angle leading to a higher lift coefficient in new stall angle and decreasing the drag coefficient. In a case study on NACA 0012 section profile results showed that the use of vortex generators increases the stall angle by 4 degrees and the lift coefficient at this point by 37%.

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عنوان ژورنال

دوره 28  شماره 2

صفحات  305- 313

تاریخ انتشار 2015-02-01

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