Method and device to prevent dust agglomeration on corona electrodes

A method for decreasing or preventing dust accumulation in an electrostatic discharge element, the element creating an electrohydrodynamic gas flow in correspondence with the electrostatic discharge, the method comprising:

• disposing a dust shroud adjacent to a sharp electrode of the electrostatic discharge element in an upstream location from the sharp electrode with respect to a direction of the gas flow created by the electrostatic discharge element so as to thereby substantially block the gas flow from impinging on the sharp electrode and prevent dust carried by the gas flow from impinging on the sharp electrode,
• wherein the disposing step includes configuring the dust shroud with substantially solid edges that are streamlined with respect to the direction of the gas flow so as to simultaneously substantially block the gas flow from impinging on the sharp electrode without substantially increasing a fluid drag of the gas flow toward a blunt electrode of the electrostatic discharge element.