A diverter for arrangement in a pipe, a barrel or a tower, and including an even number (≧4) of conical cavities arranged annularly, all of the conical cavities converging at the center of the diverter. The intersection point of the axial lines of the odd numbered conical cavities and the intersection point of the axial lines of the even numbered conical cavities are located at both sides of and symmetrical about the center of the diverter. As fluid flows through the diverter, the fluid material in the central fluid and edge zones interchange position and produce three-dimensionally intersecting flow. The diverter can efficiently improve the effects of heat and mass transfer, and can be widely used in static mixers, heat exchangers for fluid with high viscosity, temperature homogenizers of the exit of the screw extruder, high efficiency pipe reactors, and in the occasions of fluid-fluid extraction, solid-fluid extraction, etc.