Wind turbine blades

A method of manufacturing a wind turbine blade of generally hollow construction and comprising first and second half-shells;

• disposing, in each of a first and second elongated half-mould, one or more fibre cloths for respective outer skins;
• locating, in each of the first and second elongated half-moulds, first and second elongate reinforcing structures on the fibre cloths for the outer skins so as to extend along the lengthwise direction of the respective half-moulds;
• each reinforcing structure comprising a stack of layers, each stack having a thickness which extends in a direction substantially perpendicular to a surface of the respective half-mould, and the layers of each stack being of different lengths in the lengthwise direction such that the thickness of the stack is tapered towards at least one longitudinal end the stack;
• each layer extending across a width of the respective stack, the width being perpendicular to the lengthwise direction of the respective half-mould and perpendicular to the thickness of the stack, and each layer comprising at least one pre-cured pultruded fibrous composite strip;
• disposing within each of the respective half-mould core material on the fiber cloths for the outer skin so as to extend:
• (a) between the first and second elongate reinforcing structures;
• (b) from the first elongate reinforcing structure towards a leading edge of the respective half-mould;
• and (c) from the second elongate reinforcing structure towards a trailing edge of the respective half-mould;
• disposing, in each of a first and second elongated half-mould, on upper surfaces of the first and second elongate reinforcing structures and the core material, one or more fibre cloths for respective inner skins;
• supplying resin into the first and second half-moulds;
• subsequently curing the resin so as to form the first and second half-shells;
• subsequently disposing a first elongate web and a second elongate web in one of the half-moulds;
• and
• pivoting the first half-mould into a position above the second half-mould such that the first elongate web extends between the first reinforcing structure in the first half-mould and the first reinforcing structure in the second half-mould, and the second elongate web extends between the second reinforcing structure in the first half-mould and the second reinforcing structure in the second half mould.

A wind turbine blade of generally hollow construction and formed from first and second opposing half-shells;

• each half-shell comprising an inner skin and an outer skin and first and second elongate reinforcing structures being located between the inner and outer skins;
• each reinforcing structure extending along the lengthwise direction of the blade and comprising a stack of layers;
• each stack having a thickness which extends in a direction substantially perpendicular to a surface of the blade;
• each layer extending across a width of the respective stack, the width being perpendicular to the lengthwise direction of the blade and perpendicular to the thickness of the stack, and each layer comprising at least one pre-cured pultruded fibrous composite strip;
• each half-shell further comprising core material disposed between the inner and outer skins and extending:
• (a) between the first and second elongate reinforcing structures;
• (b) from the first elongate reinforcing structure towards a leading edge of the blade;
• and (c) from the second elongate reinforcing structure towards a trailing edge of the blade;
• wherein the wind turbine blade further comprises a first elongate web extending between the first reinforcing structure in the first half-shell and the first reinforcing structure in the second half-shell, and a second elongate web extending between the second reinforcing structure in the first half-shell and the second reinforcing structure in the second half-shell.