Development of new universal correlations for minimum heat flux point for saturated pool boiling of cryogens

This study addresses the critical need for a reliable database for the minimum heat flux (MHF) point in saturated pool boiling of cryogens. Relying on a comprehensive review of the relatively sparse published literature, a key objective of the study is to amass a MHF database, which is then used to investigate influences of various parameters on MHF, assess the accuracy of published correlations, and develop new correlations specifically tailored to cryogenic fluids. By applying stringent point-by-point evaluation criteria, 165 data points for MHF point temperature ( T min ) and 158 data points for MHF point heat flux ( q" min ) are aggregated, comprising this study's "Consolidated Database" for MHF. This database includes data for liquid helium (LHe), liquid argon (LAr), liquid hydrogen (LH2), 2 ), and liquid nitrogen (LN2) 2 ) and boiling from clean as well as treated (coated or oxidized) surfaces. A total of 9 correlations for T min and 10 for q" min are evaluated for accuracy against the new Consolidated Database. Leveraging insights from prior correlation results and trends from the new Consolidated Database, new universal correlations are formulated for both T min and q"min. min . The new correlation for T min features Mean Absolute Errors (MAEs) of 9.05 % for clean surfaces and 7.7 % for treated surfaces. Similarly, the new q" min correlation shows MAEs of 21.50 % for clean surfaces and 25.22 % for treated surfaces. While the new correlations represent a significant advancement in the development of predictive tools for cryogens, this study points to a need for more comprehensive experimental investigation of heat transfer aspects of cryogens, which will undoubtedly further improve the robustness and accuracy of the new correlations.