Experimental Investigation on the Aerodynamic Performance of NLF-0414 Iced-Airfoil

Abstract

Icing phenomenon on a natural laminar flow airfoil (NLF-0414) has been experimentally investigated. Double horn glaze ice geometry which was acquired during a 15 minutes spray time at−2.23℃ with liquid water content and a median volumetric diameter of 1.0 g/m 3 and 20 μm, has been extracted from database of NASA Lewis Research Center. Pressure distribution over airfoil surfacewas evaluated at angles of attack between -2 to 6 degreesfor both iced and clean airfoils. Aerodynamics performance degradation of the iced airfoil has been studied and it is shown that double horn ice accretion, due to its unique geometry, severely affects aerodynamic characteristics of natural laminar flow airfoils. Reattachment locations have been evaluated for upper and lower separation bubbles. The upper surface separation bubble was seen to increase in size in contrary to the lower surface separation bubble.

A numerical investigation of the effects of ice accretion on the aerodynamic and structural behavior of offshore wind turbine blade

“…They found that the coefficient of lift decreased and the coefficient of drag increased once the ice had formed. Ebrahimi et al (2016) conducted experimental studies on an NLF-0414 profile under well-defined icing conditions to study the degradation of its aerodynamic performance. It was determined that the accumulation of double-horn ice strongly altered the aerodynamic characteristics of the profiles and that the size of the separation bubble on the top side increased with the angle of attack, in contrast to the one located at the bottom surface.…”

Atmospheric Icing Effects of S816 Airfoil on a 600 kW Wind Turbine Performance

“…Jin et al [20] experimentally studied the e ects of a simulated single-horn glaze ice accreted on rotor blades on the vortex structures in the wake of a HAWT utilizing the stereoscopic particle image velocimetry (Stereo-PIV) technique. More recently, Ebrahimi et al [21] experimentally investigated the upper and lower separation bubbles over a Natural Laminar Flow (NLF-0414) airfoil with double horn glaze ice geometry. In addition, Manshadi and Esfeh [22] studied the characteristics of the unsteady separation bubbles on a NACA 0015 airfoil with simulated two-dimensional leading-edge glaze ice accretions.…”