Copper-slag packed-bed TES - temperature measurements
Description
This dataset contains temperature profiles measured during charging and discharging cycles of two packed-bed thermal energy storage (PBTES) configurations: an axial (A-PBTES) and a radial (R-PBTES) system. Both systems employ Chilean copper slag as the thermal storage medium and air as the heat transfer fluid (HTF). The A1 experiment corresponds to the axial configuration charged at 150 °C for 1.5 h, while the R4 experiment corresponds to the radial configuration charged at 300 °C for 3.0 h. The data show the spatiotemporal temperature evolution within each packed bed, captured by type-K thermocouples placed at different heights in the axial case and at multiple radial and axial positions in the radial case. These temperature fields illustrate the formation and movement of thermal fronts (thermoclines) during charging and discharging, allowing assessment of thermal stratification, energy storage capacity, and round-trip efficiency. In the axial configuration (A1), a clear thermocline develops along the flow direction, indicating effective stratification and a high recovery efficiency of approximately 93%. In the radial configuration (R4), higher temperatures occur near the core, resulting in a self-insulating effect and an energy recovery rate of approximately 74%. These datasets are valuable for validating heat-transfer and porous-media models for packed-bed systems, benchmarking computational fluid dynamics (CFD) or reduced-order simulations, and supporting the design optimization of thermal energy storage units that employ granular materials and industrial by-products.
Files
Steps to reproduce
The data were obtained through experimental measurements conducted on two laboratory-scale packed-bed thermal energy storage (TES) prototypes designed to operate under reversible airflow. The axial configuration (A-PBTES) consisted of a cylindrical vessel, and the radial configuration (R-PBTES) considered an annular vessel. Chilean copper slag particles (density of 3700 kg/m³ and a specific heat capacity of 1.1 kJ/kg·K) filled both beds. In both cases, the heat transfer fluid was air, driven by a centrifugal fan and heated by an electric heater with a nominal capacity of 35 kW. Temperature measurements were collected using type-K thermocouples (with a sampling interval of 10 s). Each experiment consisted of a charging phase, in which hot air was introduced into the packed bed, followed by a discharging phase using ambient air. For the A1 test, the inlet air temperature was 150 °C and the charging/discharging duration was 1.5 h. For the R4 test, the inlet air temperature was 300 °C and the charging/discharging duration was 3.0 h. Flow reversal between charging and discharging ensured symmetric heat exchange and consistent boundary conditions. The two time series show each column as temperature from a thermocouple position (in degrees Celsius) and each row as a time step (in hours). The resulting dataset enables the reconstruction and analysis of the temperature field evolution within both the axial and radial packed beds, being reproducible using the same experimental setup, instrumentation, and operating parameters described.
Institutions
- Pontificia Universidad Catolica de Chile
- Universidad Tecnologica Metropolitana
- Universidad de Santiago de Chile