Nozzle used for spraying a liquid substance towards a compressor of a gas turbine engine, comprising an elongated body having an end for ejecting the liquid substance, a conduit for the liquid substance internal to the elongated body and extending up to the end, a recess located at the end, wherein the conduit ends in the recess; wherein the recess opens towards the lateral surface of the elongated body, typically a cylindrical body, and the conduit is tangential to the bottom of the recess.