Abstract: A static fluid stirrer includes a flow channel pipe passing a fluid inside; a spiral flow forming member guiding the fluid to circle around a central axis parallel to a passing direction of the fluid to form a spiral flow in the flow channel pipe; and a spiral flow baffle member projecting from the inner wall of the flow channel pipe and baffling the spiral flow.

Abstract: An atmospheric gas generator for heat treatment includes a heat treatment furnace for performing heat treatment of a metal material; an alcohol supply device for supplying alcohol to the heat treatment furnace; a nitrogen gas supply device for supplying nitrogen gas to the heat treatment furnace; and a nozzle having an end protruding into the heat treatment furnace. An atmospheric gas is generated by introducing the alcohol supplied by the alcohol supply device and the nitrogen gas supplied by the nitrogen gas supply device into the heat treatment furnace via the nozzle. The nozzle includes an alcohol introduction pipe, a nitrogen gas introduction pipe, and a venturi section provided in connection with a tip of the alcohol introduction pipe and with a tip of the nitrogen gas introduction pipe.