BOTTOM NOZZLE FILTER DEVICE AND DEBRIS-RESISTANT BOTTOM NOZZLE USING THE DEVICE

摘要

The present invention relates to a bottom nozzle filtering device and a debris-preventive bottom nozzle that can be used for a light water reactor (LWR) nuclear fuel assembly. The bottom nozzle filtering device includes a plurality of successively spliced unit plates; a through flow channel is formed between the spliced adjacent unit plates; the flow channel includes a plurality of spaced straight-section flow inlets, and a plurality of spaced straight-section flow outlets, as well as a flow subchannel communicating with the straight-section flow inlets and the straight-section flow outlets; the outlet section of each straight-section flow inlet in the middle splits respectively into two flow subchannels, and the inlet section of each straight-section flow outlet in the middle communicates respectively with the two flow subchannels. The flow direction of the coolant is controlled by the straight-section flow inlet, the straight-section flow outlet, the flow subchannel, etc. to prevent unnecessary eddies forming, making the pressure loss effectively controlled; after a large size debris is stopped, the flow enters the flow subchannel to be filtered again, realizing staged filtering, thus improving the filtering effect.