De-icing system for a wind turbine blade

A wind turbine blade having a blade de-icing system, the wind turbine blade comprising a root end and a tip end, a leading edge and a trailing edge, a suction side and a pressure side, and an internal leading edge cavity between the leading edge and a back surface formed by at least one internal shear web or spar side of a spar extending between the suction side and the pressure side, the blade de-icing system comprising:

• a first channel longitudinally extending from a first position to a second position, wherein the second position is between the tip end and the first position;
• and
• a heating channel longitudinally extending from the second position to the first position along the leading edge of the wind turbine blade, the heating channel and the first channel being in fluid connection,
• wherein the blade de-icing system is arranged to provide a flow of heated fluid through the first channel and the heating channel, the flow of heated fluid through the heating channel having a main flow direction along a longitudinal direction of the wind turbine blade, and wherein the blade de-icing system is configured to affect the flow of heated fluid through the heating channel resulting in a rotational flow of the heated fluid about the main flow direction, and
• wherein the rotational flow is rotating from the suction side to the pressure side at the leading edge or rotating from the pressure side to the suction side at the leading edge.