arXiv subjects

Colin R. McInnes

Publications and source records attributed to Colin R. McInnes.

3 recordsLinked to original sources

arXiv2015

Low-energy capture of asteroids onto KAM tori

We present a new method for engineering the artificial capture of asteroids. Based on theories of the chaos-assisted capture of natural satellites of the giant planets, we show how an unbound asteroid that passes close to a regular region of phase space can be easily moved onto the nearby KAM tori and essentially permanently captured with the Earth's Hill sphere without closing the zero velocity curves. The method has the advantages of a relatively low delta-v requirement and no need for control strategies. An illustration of the method is given for an example asteroid trajectory, demonstrating that it is a viable strategy for the final capture stage of asteroids in the Earth's neighbourhood.

astro-ph.EP↗

arXiv2014

Passive Sorting of Asteroid Material Using Solar Radiation Pressure

Understanding dust dynamics in the vicinity of asteroids is key for future science missions and, in the long-term, for asteroid exploitation. This paper analyzes the feasibility of manipulating asteroid material by means of solar radiation pressure. A novel method is proposed for passively sorting material as a function of its grain size or density, where solar radiation pressure is used as a passive in-situ "mass spectrometer". A simplified analysis shows that in principle this method allows an effective sorting of regolith material. This could have immediate applications for a sample return mission, and for industrial scale in-situ resource utilization to separate and concentrate regolith according to particle size or composition.

math.DS↗

arXiv2006

A volume-based description of gas flows with localised mass-density variations

We reconsider some fundamental aspects of the fluid mechanics model, and the derivation of continuum flow equations from gas kinetic theory. Two topologies for fluid representation are presented, and a set of macroscopic equations are derived through a modified version of the classical Boltzmann kinetic equation for monatomic gases. The free volumes around the gaseous molecules are introduced into the set of kinetic microscopic parameters. Our new description comprises four, rather than three, conservation equations; the classical continuity equation, which conflates actual mass-density and number-density in a single equation, has been split into a conservation equation of mass (which involves only the classical number-density of the gaseous particles) and an evolution equation purely of the mass-density (mass divided by the actual volume of the fluid). We propose this model as a better description of gas flows displaying non-local-thermodynamic-equilibrium (rarefied flows), flows with relatively large variations of macroscopic properties, and/or highly compressible fluids/flows.

physics.flu-dyn↗