A new dataset with local measurement and visualization of subcooled boiling in an internally heated annulus channel

Thorough understanding of boiling characteristics of two-phase flow is essential for light water reactor design and safety analysis. However, detailed measurement of boiling flow is available only under limited conditions. In particular, two-phase transport data that includes local measurement of void fraction, interfacial area concentration, bubble size, and gas velocity at many axial locations is scarce in the open literature. Therefore, a new data set is obtained in an internally heated annulus channel. The inner and outer diameters of the annular channel are 19.05 mm and 38.1 mm, respectively, and the heated section is 3 m. For high axial resolution of the transport phenomena, five instrumentation ports are placed along the heated region of the internally heated annulus test section. Each instrumentation port houses two radial traversing mechanisms: one for a thermocouple to record local liquid temperature, and one for a four-point conductivity probe to measure local two-phase parameters. Viewports are also placed in the test section to capture the two-phase structure with high-speed video and to identify Onset of Nucleate Boiling (ONB) and Point of Net Vapor Generation (PNVG). The data set is widely beneficial for validation of system analysis codes and computational fluid dynamics (CFD) codes.