Akademik Veri Yönetim Sistemi
Applied Thermal Engineering, cilt.288, 2026 (SCI-Expanded, Scopus)
This study presents a comparative investigation into condensate water formation in a domestic gas-fired condensing boiler under varying thermal loads. By integrating experimental methods with computational fluid dynamics (CFD), the research assesses condensation and latent heat recovery at input capacities of 6, 12, 18, and 24 kW. This research stands out due to its use of infrared thermography to capture the temperature distributions on the condensation region of the combi boiler. These temperature distributions are then used as boundary conditions in a transient, three-dimensional CFD model. This approach yields a more accurate representation of phase-change dynamics in a multiphase flow environment. The results indicate that while the total mass of condensation increases with higher loads due to greater water vapor generation, the specific condensation yield per kilowatt is significantly improved at lower loads and reaches a peak value of 4.38 × 10−5 kg/s·kW at 6 kW, as thermal imaging revealed more uniform and lower surface temperatures during partial-load operation. These findings illustrate that optimal conditions for enhanced latent heat recovery are present at reduced loads. The CFD model demonstrated a strong alignment with experimental results, exhibiting a maximum deviation of 10.3 %, thereby validating its reliability for phase-change predictions. Notably, this work uniquely focuses on the condensation zone and introduces thermal imaging as an innovative source of boundary conditions. The outcomes provide valuable insights for improving boiler performance under real-world modulating conditions and underscore the importance of part-load operation for enhancing both energy efficiency and emission reduction in residential heating systems.