In order to study the phenomenon that the particles contained in the two⁃phase flow in the nuclear power plant are deposited in the pipeline under high temperature and high pressure, the mechanism of particle erosion on the pipeline is deeply explored. The similar principle and approximate modeling method are used to design and build a nuclear power pipeline. The experimental platform for the key parameters of the actual operation of the system.The results of the 30 h elbow deposition experiment show that the outer wall and inner wall of the 90° horizontal elbow are the sedimentary hot area, the outer wall axial angle of 30～45 degrees is the maximum sedimentary area, the maximum deposition of Co elements is 1.98×10－10 g on 8 mm×8 mm×3 mm sample. The results of this paper can provide data basis for radiation dose prediction and radiation protection of nuclear power plants.

In this paper, based on the background of hydrogen photolysis of water, adapts the computational fluid dynamics software combined with secondary development to numerically analyze the heat transfer process inside the solar photocatalytic reactor. A high⁃quality structured hexahedral photocatalytic reactor grid was established to analyze the temperature distribution characteristics of the solar photocatalytic reactor model numerically, compile the Gaussian heat flow and validate the model combined with the solar photocatalytic water activity evaluation system for hydrogen production. This article will focus on the effect of solar radiation on the temperature distribution of the fluid inside the reactor and the reactor under full spectrum, and study the differences in temperature distribution and causes under different conditions.