When hypersonic spacecraft are still inside the inner atmosphere, it is no problem. But, when the outer reaches are encountered, there is another problem to consider. Out in the upper and outer margins are dust and ice that are magnified with each strike on the craft's spaceframe. Less gravity has an influence on materials that behave differently in gravity bounds of the earth.
Whenever any particle strikes the space craft's surface, there is erosion and sputtering that goes down to the molecular level. Studying the way materials react to such damage and materials engineering to take into account all molecular interaction from macro to micro. Later when data is collected and move it up to bigger dimensions. This was proposed by scientists at the University of Illinois at Urbana-Champaign.
Both Doctoral student Neil Mehta working with Prof. Deborah Levin examined two materials that are used on the outer surface of streamlined shapes. These materials are smooth graphene, and rough quartz, that were used to test the hypothesis of the researchers. In the simulation, combinations of argon, silicon, and oxygen are used to set up the effects of ice and dust particles in space to cause intentional damage. Certain dynamics were established to see what is attached after the bombardment, and how the surface is, and the duration it took to cause damage to the materials. It should be noted the damage is the size of an angstrom (length of an atom).
By starting with the most minute damage to look for how the damage starts to understand the process involved. Looking at the smallest detail might be odd, but this helps to understand where it goes from there. Getting to the core of the mechanics of erosion of graphene and quarts is a big step in the right direction too. In simulating, something called fluid dynamics in a small measure needed to make it comprehensive with fuller results. it all has to do why the physics of everything, and apply it later on.
A conundrum present is how to take results from the angstrom level, and use the data to design materials as heat protection when entering the earth's atmosphere. The answer is no, and there are interceding steps to take before actual integration into the new material. All the baby steps from molecular dynamics and fluid dynamics will be vital to get it right or else. Stages will be designing the new material from the data and finalizing the model to be used. This will take in factors that will ensure the best performance based on erosion, sputtering, and pitting of the final design.
The study is based on exotic and experimental observations of how graphene and quartz behave. Putting together all data from gas and surface interactions, then how the molecules behave, and the "first principles" rule that ties everything together. As describe by Mehta that is based on the hypothesis, worked on.
Everything can be explained in such a way that ice will form flakes and crystals, to form a trellis on the surface. Compared to dust that just scatters all over the place, and ice will cause build ups too. In degradation, the graphene will have damage on the level before it. It depends on the material used and how hypersonic craft will benefit from material developed from computational fluid dynamics or large-scale simulation.
Related Article: Surface Damage to Vehicles Traveling at Hypersonic Speeds From Ice and Dust Particles
