An improved interlayer, spar cap and wind turbine blade

A flow-enhancing fabric (1) extending in a longitudinal direction (6) and in a transverse direction (8), the fabric comprising a plurality of fibre layers including a first fibre layer (10) and a second fibre layer (20) arranged upon each other, the first fibre layer (10) comprising a first plurality of fibre bundles oriented in parallel in a first fibre direction (16) and comprising a plurality of first glass fibre bundles (14) and a number of first carbon fibre bundles (13), and the second fibre layer (20) comprising a second plurality of fibre bundles oriented in parallel in a second fibre direction (26) different from the first direction and comprising a plurality of second glass fibre bundles (24) and a number of second carbon fibre bundles (23), so that at least a number of first carbon fibre bundles (13) intersect and contact a number of second carbon fibre bundles (23), and the fabric further comprises a plurality of monofilaments (30) arranged between the first and second fibre layer (10, 20) along the transverse direction (8) of the fabric, the plurality of monofilaments (30) each having a mutual spacing (31) between them.

A spar cap (100, 7400, 7600) for a wind turbine blade (1000) comprising a plurality of electrically conductive precured fibre-reinforced elements including a first precured fibre-reinforced element (50) and a second precured fibre-reinforced element (60), wherein a flow-enhancing fabric (1) according to claim 1 are arranged between the first precured fibre-reinforced element (50) and the second precured fibre-reinforced element (60).