The flow boiling experiments were performed in 2×2 rod bundle channel using a medium-high pressure thermal-hydraulic experimental platform. The two-phase parameters were measured at various heat flux, inlet subcooling, and pressure at localized positions, resulting in a total of 41 operating conditions. The experimental data for bubble behavior in the heated condition subchannel included measurements of void fraction, interfacial area concentration, bubble velocity, and bubble chord length. The voltage signals generated by double sensor conductivity probe were collected using an NI data acquisition card and stored in TDMS file format. Signal recognition and matching are essential during the data processing stage utilizing Matlab. Both the experimental circuit and the experimental object employ K-type armored thermocouples for temperature measurement, exhibiting a measurement error within ±0.5℃. The pressure and differential pressure gauge (Chuanyi PDS403H-1FS0-A1NA/G61) demonstrates a collection accuracy of 0.075%. The flow meter (3351-DP33M3B3F22 pressure transmitter) has an acquisition accuracy of 0.05%. Temperature data is collected through the use of NI 9212 and NI 9213 data acquisition cards, with collection accuracies of ±0.0093 mV and 6 μV respectively. The pressure, pressure difference, and flow rate data are collected using the NI 9205 data acquisition card, with a collection accuracy of ±3.23 mV. The uncertainties associated with the void fraction, interfacial area concentration, bubble velocity, and bubble chord length measured using the double sensor conductivity probe are 7.56%, 13.61%, 13.61%, and 11.32% respectively.
