| 摘要 |
A structural shell for a wind turbine blade is formed from one or more elongate reinforcing members, each in the form of a stack (3) of pultruded fibrous composite strips positioned between two layers of structural foam (4). The foam layers (4) have a thickness which is greater than that of the stack (3). The edges of the foam layers (4) are formed with a void (11). With the stack (3) and foam layers (4) positioned in a mould, a strip of pre-cured glass fibre (5) is placed on the stack (3) and the edges of the foam layers (4). A vacuum is applied to the stack (3) and the foam layers (4), causing the glass fibre strip (5) to press on the stack (3) and foam layers (4) and to conform to the underlying surfaces. As a result, the void (11) is reduced in size and the step-shaped transition between the surfaces of the stack (2) and the foam layers (4) transformed into a smooth transition, so as to reduce the stresses within the glass fibre strip (5) in the region of the abutment of the stack (3) and the foam layers (4). In other embodiments, the stepped transition is smoothened by replacing the upper-edge region of each foam layer (4) with a strip of low-stiffness foam. |
