Wind turbine blade apparatus and wind turbine blade attachment member

An attachment member for a wind turbine blade to be attached to at least a part of a trailing edge of a wind turbine blade body, the attachment member comprising:

• a first-surface side wall surface to be disposed on a first surface of the wind turbine blade body;
• and
• a second-surface side wall surface to be disposed on a second surface of the wind turbine blade body, the second-surface side wall surface being connected to the first-surface side wall surface via a trailing edge portion,
• wherein trailing-edge portion sides of the first-surface side wall surface and the second-surface side wall surface are formed into a saw-teeth shape where a mountain portion and a valley portion are arranged alternately,
• wherein each of a ridge line of the mountain portion and a valley line of the valley portion, which connects adjacent teeth of the saw-teeth shape, is configured to extend along the chord direction of the wind turbine blade body, and
• wherein a chord-directional cross section of the wind turbine blade body along the chord direction is formed to have an airfoil shape at any position in a region from the ridge line of the mountain portion to the valley line of the valley portion.