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Faryniarz, Luke J.

Mechanical Engineering

2014

MS

Current advances in micro-fabrication technology have allowed for both the design and production of next generation miniaturized satellites (commonly referred to as 'nanosats'). Due to the limited research, testing and simulation that has been performed on nanosats to date, specifically the micro-propulsion systems used to control their movement in a zero gravity atmosphere, the expected performance characteristics of nan-satellites are not yet fully understood.
However, by deriving and numerically solving the mass, momentum, energy and species conservation equations governing the micro-propulsion system (specifically, the monopropellant fuel decomposition process), while simultaneously making use of various constitutive relationships between system state variables, a mathematical model describing the physical behavior of the system can be obtained as a series of differential equations representing the conservation of thermodynamic properties in the domain of the decomposition chamber. Once this model has been established, this will provide engineers with a baseline for modifying the propulsion system (in terms of both the physical design and operating conditions) of the satellites to achieve optimal performance outputs.
Here, we examine a mathematical model for a propulsion mechanism characterized by the decomposition of a hydrogen peroxide monopropellant flow within a microchannel channel containing staggered pillars coated with ruthenium oxide catalyst. Due to the complexity of the equations describing the microscale, multiphase, chemically reacting flow through a porous media, which collectively characterize the decomposition process, the solutions are approximated using finite volume numerical methods.