Advances in the Whipple Shield Design and Development:

Safety of satellites as well as spacecrafts during space missions is a primary objective to preserve the physical and virtual assets onboard. Whipple shields belong to the class of protective equipment provided on the surface of the spacecrafts and satellites, to sustain impacts from the ultra-high speed debris, which can otherwise cause considerable damage to the corresponding structures. Recent works on whipple shields are focussed on determining the response of different geometrical arrangements and material properties under hyper-velocity impact at projectile speeds of 3-18 km/s. Advances in the whipple shield design include integrated and mechanised models employing high performance materials like fiber-metal laminates ensuring better operational capability. The forward bumper of the whipple shield is the first line of defence as it regulates the state of projectile after the primary impact. Use of aluminium alloys for front bumpers is popular, owing to their lightweight and strength characteristics. The advances for the front bumper have seen usage of ceramic, metallic foams, and super composite mixtures, which resulted in enhanced performance, durability and safety of the whipple shields. This work is a comprehensive coverage of the latest materials used for whipple shields, their performance characterization—both experimental and theoretical, and applications.

An Alternative Ballistic Limit Equation for the Whipple Shield in the Shatter Regime, Based on Characteristics of the Large Central Fragment

In the shatter regime of a Whipple shield, a large central fragment makes a significant contribution to the damage-causing capacity of the debris cloud. Herein we present a feasible scheme for the identification and measurement of this large central fragment and propose an alternative approach to the ballistic limit equation (BLE) for the Whipple shield, deducing an alternative ballistic limit in the shatter regime based on the large central fragment’s characteristics. This alternative BLE is compared with the phenomenological Whipple BLE, the JSC Whipple BLE and the Ryan curve. Our alternative BLE, modified at the incipient fragmentation and completed fragmentation point, is shown to agree well with experimental results.

Numerical Simulation of Ti-Based Metallic Glasses as Whipple Shield Bumper by Smoothed Particle Hydrodynamics Methods

The debris clouds produced by hypervelocity impacts on Ti-based metallic glasses (Ti-MGs) and Al-6061-T6 bumper were studied by smoothed particle hydrodynamics (SPH) methods. The change of the vanguard shape, dispersion and ejection angle were also obtained with the same bumper thickness to the projectile-diameter ratio (h/d). For the same h/d valve, the debris cloud of Ti-MGs bumper had a more widely dispersion and ejection angle than with Al-6061-T6 bumper; the vanguard velocity of Ti-MGs bumper was also lower than Al-6061-T6 bumper. Moreover, for the same bumper areal density, the vanguard of the debris cloud in MGs bumper was plane-shaped. This study demonstrates that Ti-MGs exhibit an excellent bumper protection performance, which asset can pave new paths for their further applications.