Learning Forum

[MechEngStud]

why is it the Power Coefficient (Cp) of slotted airfoil wind turbine blade has a higher value at low tsr compare to a normal wind turbine blade? But as the tsr increases the Cp of slotted airfoil blade decreases so much compare to a normal wind turbine blade?

[Rob]

What does the literature say on the matter? Have you modelled both?

[MechEngStud]

yes i modelled both. the slotted airfoil wind turbine has a higher Cp at low tsr compare to the baseline blade. but as the tsr increases the Cp of the slotted airfoil wind turbine blade has a lower Cp compare to the baseline blade.

[Rob]

OK, assuming you've taken area etc into account for the coefficient what does literature say about the benefits (or otherwise) of slotted blades?

[MechEngStud]

It delays the separations of fluid at the tail end of the airfoil becoz the slot re energize the streanlime delaying the drag. in low tsr, the slot is effective but in high tsr the slot is a disadvantage as it decreases the value of Cp. my question is why is this phenomenom happening? care to explain?

[Rob]

It'll be linked to boundary layer separation and turbulence. That's one for the Courses, or a text book.