Prospective of Self-Pressurized Technology for In Space Satellite Mission
Creators: name:  S. LA LUNA 
name:   F. MAGGI 
name:   D. ZUIN 
Publisher: name: Proceedings of  the 9th European Conference for Aerospace Sciences. Lille, France, 27 June - 1 July, 2022
Year: 2022
Subjects: PROPULSION PHYSICS
LIQUID ROCKET ENGINE
SYSTEMS
NEW DEVELOPMENTS

description: In recent years, the satellite market has experienced significant changes: the number of satellites has increased rapidly and projections forecast a 300% increment in satellite numbers within the next five years. Competition among companies is pushing the application of innovative design solutions, manufacturing, assembling, and testing in order to reduce complexities, costs, and to achieve competitive advantages. To maintain the small satellites and CubeSat market growth pace, space companies are developing subsystem architectures where mass and volume are minimized. The effort is justified by the quest of the companies of increased allowance for payloads. Self-pressurized technology is one examples of innovation in the field of space propulsion, enabling the reduction of volumes. Self-pressurization physical phenomenon is exploited in order to expel a liquid or gas stored in a closed vessel by utilizing the internal energy of the liquid itself. The system does not require any pump and external pressurization devices, allowing a reduction in complexity, costs, and weight. An added value to the technology is provided by the ease in feeding line design schemes and assembly within Liquid Rocket Motors applications. Other possible simplification of this technology are the possibility to discharge in liquid or vapour phase, thus simplifying the use of PMD, the reduced power consumption with respect to pump-fed architectures (no pump are present in the circuit) and the high reliability of the self-pressurization process over long periods (it is a physical phenomenon). Potential applications of these systems are widespread in the space segment and not limited to the propulsion panorama: from on-orbit maneuvering to in-orbit servicing, from refuelling of satellites at end of life to in-situ resources exploitation for missions headed towards remote objects of the solar system. The development of Vapor Pressurization systems, also called VaPak, has started in 1959 by Aerojet and in the last 50 years its physics has been studied and validated by a large number of tests. However, important drawbacks have been reported for these systems: modelling of fluidic and thermal phenomena is complex, so that accurate performance predictions are prevented; as a result, no comprehensive model to accurately describe the dynamics of a self-pressurizing propellant tank has been developed so far. Within the scientific panorama, three main models are implemented in order to simulate the dynamics of these systems: Equilibrium (EQ) model, Zilliac-Karabeyoglu (ZK) model and Casalino-Pastrone (CP) model. The aim of this paper is to describe the self-pressurized phenomena starting from the three models aforementioned and to verify the possible advantages, disadvantages and perspectives of this technology for in space satellite missions. The actual state of the art of self-pressurized liquid propulsion for in orbit space maneuvering is described and the need for a different approach to the problem in view of future space missions is addressed and justified; the description of the novel topics is detailed, starting from the reasons why they were not treated in the past up to the analysis of the complexities associated to the modelling of these systems. Green and storable propellants will be settled to analyze the system, and a possible propulsion subsystem architecture will be proposed.