Quantum mechanics

Engineering

Aerospace engineering

Meteoroid

Materials science

Acoustic emission

Acoustics

In situ

Projectile

Physics

Astronomy

Electromagnetic shielding

Composite material

Space debris

Structural engineering

Spacecraft

Meteorology

Hypervelocity

Micrometeoroid

International Journal of Impact Engineering

Pervasive in outer space, hypervelocity impact (HVI), caused by man-made debris (a.k.a. space junk) and natural micrometeoroids, poses a clear and tremendous threat to the safe operation of orbiting spacecraft, and it will possibly lead to the failure of a space exploration mission. Addressing such an issue, damage in a downscaled two-layer space shielding assembly, engendered by HVI events with an impact velocity up to 4 km/s, was characterized quantitatively, using in-situ measured acoustic emission (AE) induced under HVI. A hybrid model, based on three-dimensional smooth-particle hydrodynamics and finite element, was developed, to achieve insight into the traits of HVI-induced AE waves and HVI-caused damage. Proof-of-concept simulation was accomplished using the hybrid model, in which a projectile, at various impact velocities, impinged a series of shielding assembly of different thicknesses, in a normal or oblique manner. Experimental validation was implemented, and HVI-induced AE waves were in-situ acquired with a built-in piezoelectric sensor network integrated with the shielding assembly. Results from simulation and experiment show qualitative consistency, demonstrating the capability of the hybrid model for depicting HVI-produced shock waves, and the feasibility of in-situ measurement of HVI-induced AE signals. Taking into account the difference and uniqueness of HVI against other ordinary impact cases, an enhanced, delay-and-sum-based imaging algorithm was developed in conjunction with the built-in sensor network, able to "visualize" HVI spots in pixelated images accurately and instantaneously.

Characterizing hypervelocity (&gt;2.5 km/s)-impact-engendered damage in shielding structures using in-situ acoustic emission: Simulation and experiment

Characterizing hypervelocity (&gt;2.5 km/s)-impact-engendered damage in shielding structures using in-situ acoustic emission: Simulation and experiment

Characterizing hypervelocity (>2.5 km/s)-impact-engendered damage in shielding structures using in-situ acoustic emission: Simulation and experiment