Spanwise forcing for turbulent drag reduction: An experimental investigation into active and passive flow control

Turbulent drag reduction (DR) is a crucial research area, as this can contribute to significant energy and emission reductions in various industrial and transportation applications. One such technique is the active flow control method of spanwise forcing. Spanwise forcing introduces a spatio-temporal spanwise wall oscillation as a boundary...

Wall-normal pores for turbulent drag reduction: Experimental investigation into drag performance and flow mechanics

Flat surfaces with arrays of wall-normal pores called micro-cavity arrays have shown potential to reduce turbulent skin friction drag. Their designs have been inspired by acoustic liners which are sandwich panels consisting of a honeycomb core, a perforated top plate and a solid back sheet used on...

Rotating Discs for Turbulent Drag Reduction: An Experimental Study

The reduction of turbulent skin-friction drag has the potential to generate numerous societal benefits. In large-scale industrial applications, the largest share of energy consumption goes into overcoming the friction drag produced by turbulent boundary layers formed on the outside wall. Estimates assess that over 50% of the total fuel burn is...