Continuous Correlations for Complete Boiling Curves of Cryogenic Fluids

Future space exploration missions will rely on in situ production, storage, and transfer of cryogenic rocket propellants. Engineers need accurate and efficient modeling tools to design the next generation of lightweight, efficient cryogenic propellant management devices and processes. Predictive models for key fluid dynamics and heat transfer behavior must be tailored for use with cryogenic propellants and easily implemented in existing modeling frameworks. To meet this need, we propose to develop a suite of pool boiling correlations developed specifically for common cryogenic fluids and propellants, including hydrogen, oxygen, and methane. In Phase I, we proved the feasibility of our approach by measuring critical heat flux for cryogenic nitrogen and argon under novel conditions, assembling a comprehensive database for CHF in cryogenic fluids, and developing correlations for critical heat flux (CHF) that beat NASAs requirements for predictive accuracy and are more accurate than existing correlations. In Phase II, we will create a database of existing cryogenic pool boiling data for all boiling regimes from the literature. We will augment the database with new data collected from our cryogenic pool boiling test apparatus in both steady boiling and quenching modes, and we will produce new correlations that are piecewise smooth across all pool boiling regimes.
Benefits: Improved pool boiling correlations tailored for cryogenic fluids will benefit the design of propellant transfer, management, and storage systems for oxygen, methane, and hydrogen as part of critical programs such as the Human Landing System. Our improved correlation will help minimize chilldown times, minimize liquid venting during propellant fill, and design systems to prevent propellant boiloff due to static heat gain during operations. CFM is also important for electronics cooling, directed-energy weapons cooling, and liquid natural gas storage and transport. Our pool boiling heat transfer correlations will support the design of these systems for high efficiency.