The paper presents a preliminary study and development for a lunar In Situ Resource Utilisation (ISRU) plant. To make the human space colonisation a fundamental step is represented by enabling technologies to exploit local resource, limiting a periodical refurbishment from Earth. Here a possible technological demonstrator mission is deeply analyzing taking care of any possible technological and design trade-offs. Firstly the selection of the material to be treated is presented, based on the analysis of the available resources on our satellite. As a second step the different methods of extraction are compared and the process of oxygen manufacturing is proposed as the most important element to both support life and supplying fuel for propulsion applications. Oxygen manufacture can be obtained thanks to different processes such as the hydrogen reduction of ilmenite, molten silicates electrolysis, pyrolisis and carbothermal reduction of anorthite. The last has been selected for the presented design as it offers the best compromise in terms of feasibility and innovation. The Malapert Mountain turned out to be the zone with the best-suited superficial soil composition to collect the anorthite, having a smooth morphology, quite good light exposition too. The requirements the ISRU technological demonstrator has been design include the production of 3-5 kg oxygen within 6 months. Moreover, the exploitation of a European launcher such the Ariane 5 is has been posted. As a consequence, strong limitations on launcheable mass and ISRU dimensions must have been taken into account while sizing. Five modules - each of which has been preliminarily designed - compose the overall plant. To better understand and analyze the feasibility and the process effectiveness the dynamic model of the entire plant has been implemented. The dynamic modelling of the ISRU demonstrator helped in refining the preliminary design of the modules and to simulate different operational mode of the plant itself. The ISRU architecture includes the following modules: 1. a Beneficiation modulus, whose aim is the selection of fine particles of anorthite from other species in order to satisfy reactor requirements; 2. a Reactor, the core of the system, i.e. the chamber where the reaction of reduction with methane takes place and monoxide and hydrogen are produced; 3. a Reverse Steam Reforming chamber, where water and methane are obtained from monoxide an hydrogen, coming from reactor and tanks where a surplus of hydrogen is stowed; 4. a Water Electrolysis modulus, where oxygen and water are produced from water; 5. a Power Generation system, which provides required power to every unit thanks to solar panels and fuel cells. A previous research and study in the field of analogous applications on Earth and Moon was followed by a thorough analysis to define the best configuration, in terms of dimensions and dynamic respond, which fitted in with mission requirements. Dynamic simulation needed the identification of mathematical model, capable of describing behaviours of every system. Thanks to this operation a numerical model was built in Matlab/Simulink environment. A parametrical analysis was conducted: this allowed to define running performances of every system and to describe different situations, such as non-optimal or critical working conditions. This part of the study involved an important contribution to dimensional statements and it could be a starting-point to improve reliability. The result of the dynamic analysis was the creation of a dynamic model library which represents and describes every single modulus of the unit, whose elements can be interfaced to simulate the behaviour of the entire unit. This kind of approach to the problem allowed us to create completely parametrical elements of the library, applicable to bigger-size systems, flexible because they can be interfaced in many ways to solve different configurations, and integrable with external components.
A in Situ Resource Utilisation Demonstrator for the Moon: Preliminary Design and Dynamic Model
LAVAGNA, MICHÈLE;GRASSO, MARCO LUIGI
2007-01-01
Abstract
The paper presents a preliminary study and development for a lunar In Situ Resource Utilisation (ISRU) plant. To make the human space colonisation a fundamental step is represented by enabling technologies to exploit local resource, limiting a periodical refurbishment from Earth. Here a possible technological demonstrator mission is deeply analyzing taking care of any possible technological and design trade-offs. Firstly the selection of the material to be treated is presented, based on the analysis of the available resources on our satellite. As a second step the different methods of extraction are compared and the process of oxygen manufacturing is proposed as the most important element to both support life and supplying fuel for propulsion applications. Oxygen manufacture can be obtained thanks to different processes such as the hydrogen reduction of ilmenite, molten silicates electrolysis, pyrolisis and carbothermal reduction of anorthite. The last has been selected for the presented design as it offers the best compromise in terms of feasibility and innovation. The Malapert Mountain turned out to be the zone with the best-suited superficial soil composition to collect the anorthite, having a smooth morphology, quite good light exposition too. The requirements the ISRU technological demonstrator has been design include the production of 3-5 kg oxygen within 6 months. Moreover, the exploitation of a European launcher such the Ariane 5 is has been posted. As a consequence, strong limitations on launcheable mass and ISRU dimensions must have been taken into account while sizing. Five modules - each of which has been preliminarily designed - compose the overall plant. To better understand and analyze the feasibility and the process effectiveness the dynamic model of the entire plant has been implemented. The dynamic modelling of the ISRU demonstrator helped in refining the preliminary design of the modules and to simulate different operational mode of the plant itself. The ISRU architecture includes the following modules: 1. a Beneficiation modulus, whose aim is the selection of fine particles of anorthite from other species in order to satisfy reactor requirements; 2. a Reactor, the core of the system, i.e. the chamber where the reaction of reduction with methane takes place and monoxide and hydrogen are produced; 3. a Reverse Steam Reforming chamber, where water and methane are obtained from monoxide an hydrogen, coming from reactor and tanks where a surplus of hydrogen is stowed; 4. a Water Electrolysis modulus, where oxygen and water are produced from water; 5. a Power Generation system, which provides required power to every unit thanks to solar panels and fuel cells. A previous research and study in the field of analogous applications on Earth and Moon was followed by a thorough analysis to define the best configuration, in terms of dimensions and dynamic respond, which fitted in with mission requirements. Dynamic simulation needed the identification of mathematical model, capable of describing behaviours of every system. Thanks to this operation a numerical model was built in Matlab/Simulink environment. A parametrical analysis was conducted: this allowed to define running performances of every system and to describe different situations, such as non-optimal or critical working conditions. This part of the study involved an important contribution to dimensional statements and it could be a starting-point to improve reliability. The result of the dynamic analysis was the creation of a dynamic model library which represents and describes every single modulus of the unit, whose elements can be interfaced to simulate the behaviour of the entire unit. This kind of approach to the problem allowed us to create completely parametrical elements of the library, applicable to bigger-size systems, flexible because they can be interfaced in many ways to solve different configurations, and integrable with external components.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
