Experimental data on pool boiling of water on tube bundles at 3–5 kPa

The files include the data presented in the manuscript entitled “Experimental study of pool boiling on tube bundles at 3 to 5 kPa” by D. Kaczmarek-Piąstka, T. Hałon, and B. Zajączkowski (DOI: 10.1016/j.ijheatmasstransfer.2025.127878).This dataset includes raw experimental data on pool boiling of water on copper tube bundles at subatmospheric pressures (3–5 kPa) for compact, staggered geometries relevant to low-temperature evaporators. Experiments were conducted on both isolated tubes and vertically aligned pairs (tandem configuration) to assess the effects of hydrostatic head and inter-tube interactions. The test geometry employed 25.4 mm tubes with matching pitch. Boiling curves were obtained for multiple configurations, and high-speed visualization captured bubble dynamics and vapor transport. Results are presented for both constant and gradually decreasing subcooling.The presented data enabled the determination of the boiling curves reported in the manuscript entitled “Experimental study of pool boiling on tube bundles at 3 to 5 kPa”, as well as the heat transfer coefficient–heat flux (HTC–heat flux) relationship.The dataset contains:1. Raw data acquired using a Keithley DAQ6510 data acquisition system (DAS) equipped with two Keithley 7702 multiplexer modules, provided in comma-separated values (CSV) format compatible with Microsoft Excel.2. High-speed video recordings captured using a FASTCAM Mini UX50 camera equipped with a Sigma 18–250 mm f/3.5–6.3 macro lens and controlled via Photron FASTCAM Viewer (PFV4) software.3.An Excel file containing atmospheric pressure values recorded on each measurement day using a Testo 552 digital vacuum gauge, as well as heater power values determined as the average of the readings at the beginning and end of each measurement point, acquired from the modular voltage controller (RM50001).Data organization:1. According to tube position within the bundle and the number of tubes: bottom row, top row, and tandem tubes.2. According to the liquid height above the tube and the vapor pressure in the evaporator: Lh = 0 cm (base level) / Lh = 20 cm, and Pv = 3 kPa / Pv = 5 kPa. Due to the large volume of the complete dataset, each category includes one representative experimental series and a selected high-speed recording corresponding to a chosen imposed heat flux.