Airfoils

Based on the airfoil/blade section profile design tool, AIRFOILOPT, developed at Risø three airfoil families have been designed at Risø. The three designs have been documented in the Velux Open Jet facility and by using the computational tools XFOIL and the in-house CFD code, EllipSys2D

Risø-A1: This airfoil family is designed for stall and active stall regulation and has the relative thicknesses 15% to 33%. It has medium maximum lift coefficient, CL, around CL=1.4 to 1.5 depending on the Reynolds number and it has smooth stall characteristics.

Risø-P: The characteristics of this airfoil family are close to the Risø-A1 family, but are tailored for pitch regulated wind turbines. The family has the relative thicknesses 15% to 24%.These airfoils have as well medium maximum lift coefficient, CL, around CL=1.4 to 1.5 depending on the Reynolds number and they have smooth stall characteristics.

Risø-B1: This airfoil family is designed for wind turbines with Pitch Regulation Variable Speed (PRVS) and has the relative thicknesses 15% to 53%. It has high maximum lift around CL=1.6 to 1.9 depending on the Reynolds number and has low sensitivity of the performance to contamination of the airfoil surface.