State-of-the-art and review of condensation heat transfer for small modular reactor passive safety: Experimental studies

•The available datasets are vital for quantifying critical thermal-hydraulic properties that affect the condensation rate.•The previous test datasets have not adequately addressed the impact of the containment wall geometries on condensation performance for SMR containment walls.•Experimental datasets from steam-release accidents to long-term cooling and supportive correlations for SMRs are still missing. This study focused on state-of-the-art and review of condensation heat transfer for small modular reactors (SMR). Nuclear reactors adopt passive containment cooling systems (PCCS) for accident mitigation, containment integrity, and primarily to maintain the last barrier for radioactive particle release to the environment during and beyond design-basis accidents. However, improving the effectiveness of the PCCS is more critical for the SMR than for commercial reactors to ensure higher safety margins and compactness. In the PCCS of SMR, due to its smaller size containment, the filmwise condensation (FWC) is dominant. Therefore, this study emphasized the FWC. Earlier condensation studies for the PCCS did not make SMR the primary focus, so a critical review for formulating the state-of-the-art was necessary. Part-1 of this study covered the review of physics phenomena, previous experimental studies with a brief overview of associated test facilities and empirical correlations. This study identified a research gap with the condensation test data scaling relations by using the information and findings of the previous PCCS studies and applied them to the SMR system.