Problem to be solved: to provide a new technique for bringing the flow in the channel to a desired state.Solution: the fluid sterilization apparatus 20 includes a flow path tube 22 in which a process flow path 36 in which the passing fluid is sterilized is formed, a first light source 28 for irradiating ultraviolet rays toward the processing flow path 36, an inflow passage 42b formed in a direction intersecting the outer peripheral surface 22c of the flow path tube 22, and an inflow passage A communication passage 78 for communicating B and the processing flow path 36 is provided.The communication passage 78 has a narrow passage 80 which is narrower than the inflow passage side toward the opening 22d of the first end portion 32 of the flow passage tube 22 from the inflow passage 42b.Diagram【課題】流路内の流れを所望の状態に近づける新たな技術を提供する。【解決手段】流体殺菌装置20は、通過する流体が殺菌処理される処理流路36が形成されている流路管22と、処理流路36に向かって紫外線を照射する第1光源28と、流路管22の外周面22cと交差する向きに形成された流入路42bと、流入路42bと処理流路36とを連通する連通路78と、を備える。連通路78は、流入路42bから流路管22の第1端部32の開口22dへ向かう途中に、流入路側よりも狭くなった狭路80を有する。【選択図】図5
