Hyperthermal atomic oxygen effects on satellite systems

The University of Manchester is developing a unique experimental facility that replicates hyperthermal atomic oxygen flux in very low Earth orbits (VLEO), essentially a rarefied flow wind tunnel, called the Rarefied Orbital Aerodynamics Research Facility (ROAR). It will be a unique facility able to characterise the reemitted flow from surfaces and thereby determine their aerodynamic properties. The student will be one of the few PhD students with access to the ROAR facility, being able to participate in its set up, working to support its optimization beyond existing funded projects, and developing new technologies which can be validated using the facility.

Whilst much materials science has been carried out on atomic oxygen erosion, almost none exists in relation to the beam scattering characteristics of materials and therefore their aerodynamic properties. This has implications for aerodynamic optimisation for drag minimization and aerodynamic control, and for atmospheric sensor development. In addition, the erosion characteristics of novel materials, as well as systems such as solar array interconnects, need to be characterized.

The student is still in their first year, but the project is narrowing down on possible directions:

The student will help to answer a number of research questions:
1. How closely does ROAR reproduce the aerodynamic and erosion effects of the real VLEO environment, and what improvements can be made to create better alignment?
2. How can the flow density of ROAR be improved to allow more rapid erosion experiments?
3. How can we determine the flow direction in VLEO to support aerodynamic control methods and other applications?
4. Does a greater understanding of gas surface interactions with hyperthermal atomic oxygen affect the design of systems and sensors?

Based on experimental results the student will work to develop the fundamental science of gas-surface interactions of the atmosphere with surfaces, and work to improve the performance of ROAR and how well it represents the real VLEO environment.

Depending on the studies during the PhD, specific activities could include:
Developing improvements to ROAR to increase the atomic oxygen flux enabling erosion studies of materials and satellite systems.
Developing VLEO sensors, such as a flow sensor, for use with aerodynamic attitude control concepts and other applications.
Comparing materials performance from satellite flight data with that from ROAR to determine what changes to the system may be required to more closely replicate the VLEO environment, and how these could be implemented.
Use gas surface interaction data to inform the design of sensors and systems