Abstract: A spray nozzle which transforms a stream of water into a thin-walled tubular sheet which is atomized over a hydrostep. The nozzle comprises a body, the main portion of which has a cylindrical contour and a central passage of venturi shape, with the passage being of cloverleaf formation in horizontal cross-section, presenting a plurality of helical recesses which open onto the venturi passage. The lower end of the latter is generally bell-shaped and formed with a cylindrical hydrostep. A conduit for air under pressure enters the venturi passage from the upper end of the body and has a discharge end at the axis of the venturi passage and slightly above its waist.

Abstract: A flow preconditioner for an electrostatic precipitator which removes particulate matter from a stream of polluted gas immediately after it passes through a tangential inlet at the lower end of a vertical cylindrical housing and straightens and divides the stream into laminations parallel to the axis of the housing. It comprises an annular ledge or choke ring extending inwardly from said housing above the inlet and an assembly of vanes above said ledge extending radially from the axis of the housing and angularly spaced apart. Each of said vanes has a flow receiving edge directed toward said inlet, a curved portion extending upwardly and away from said inlet, and a flat portion extending upwardly from said curved portion in a plane parallel to the housing axis.