TY - JOUR N2 - Nitrous oxide is often used in the space industry, as an oxidiser or monopropellant, mostly in self-pressurised configurations. It has potential for growth in use due to the recent rising interest in green propellants. At the same time, modelling the behaviour of a self-pressurising nitrous oxide tank is a challenging task, and few accurate numerical models are currently available. Two-phase flow, heat transfer and rapid changes of mass and temperature in the investigated system all increase the difficulty of accurately predicting this process. To get a get better understanding of the emptying of a self-pressurised nitrous oxide tank, two models were developed: a phase equilibrium model (single node equilibrium), treating the control volume as a single node in equilibrium state, and a phase interface model, featuring a moving interface between parts of the investigated medium. The single node equilibrium model is a variation of equilibrium model previously described in the literature, while the phase interface model involves a novel approach. The results show that the models are able to capture general trends in the main parameters, such as pressure or temperature. The phase interface model predicts nitrous oxide as a liquid, a two-phase mixture, and vapour in the lower part of the tank, which is reflected in the dynamics of changes in pressure and mass flow rate. The models developed for self-pressurisation, while created for predicting nitrous oxide behaviour, could be adapted for other media in conditions near vapour– liquid equilibrium by adding appropriate state equations. L1 - http://www.journals.pan.pl/Content/124799/PDF-MASTER/art08_int.pdf L2 - http://www.journals.pan.pl/Content/124799 PY - 2022 IS - No 3 EP - 173 DO - 10.24425/ather.2022.143176 KW - Convective mass transfer KW - nitrous oxide KW - Hybrid rocket engine KW - Two-phaseflow KW - Self-pressurisation A1 - Szymborski, Jakub A1 - Kardaś, Dariusz PB - The Committee of Thermodynamics and Combustion of the Polish Academy of Sciences and The Institute of Fluid-Flow Machinery Polish Academy of Sciences VL - vol. 43 DA - 2022.10.20 T1 - Novel model for emptying of a self-pressurised nitrous oxide tank SP - 141 UR - http://www.journals.pan.pl/dlibra/publication/edition/124799 T2 - Archives of Thermodynamics ER -