The role of a composite polycarbonate-aerogel face shield in protecting the human brain from blast-induced injury: A fluid–structure interaction (FSI) study

Abstract

Background Blast-induced traumatic brain injury is the most prevalent injury sustained by combat soldiers at the frontline. The current study aims to investigate the effectiveness of composite polycarbonate-aerogel face shields with different configurations in mitigating blast-induced brain injuries. Method A series of dynamic fluid–structure interaction simulations of a helmeted head subjected to a frontal free field blast was performed, to evaluate the effectiveness of the current conventional polycarbonate face shield and three other composite face shields with different configurations when exposed to a frontal free-field blast. Results The simulation results demonstrated that the sandwiched structured face shields of polycarbonate and aerogel provided superior blast attenuation than a single-layered polycarbonate face shield. The alternate multi-layered transparent materials of high and low densities provided the best attenuation of blast pressure transmission to the head, with the polycarbonate exterior shell casing contributing to the structural integrity of the face shield, while the lower dense aerogel filler providing high acoustic impedance to blast wave transmission. Conclusion This study provides further insights on future development and design of personal protective equipment in mitigating blast-induced injuries to the head.

Protective Performance of Helmets and Goggles in Mitigating Brain Biomechanical Response to Primary Blast Exposure

“…Goggles act similar to a face shield or a visor. Several studies 31,33,36,39,43 have shown the excellent ability of face shields in mitigating the ICP. For example, Tse et al 43 studied the protective performance of single-layered and multi-layered face shields for frontal blast exposure.…”

“…Several studies 31,33,36,39,43 have shown the excellent ability of face shields in mitigating the ICP. For example, Tse et al 43 studied the protective performance of single-layered and multi-layered face shields for frontal blast exposure. They showed that the multilayered face shield provides a better blast wave attenuation performance, as it benefits from the polycarbonate exterior shell for structural integrity and inner aerogel filler for blast wave mitigation.…”

“…49 Most previous studies used the ICP, strain or strain rate as criteria to assess the bTBI. 12,18,20,36,37,39,43,50 Up to date, no studies have investigated the effect of protective equipment on CSF cavitation. Another limitation of the previous studies is the lack of detailed brain anatomy description in the human head model, which may affect the biomechanical responses of brain to blasts.…”

Polyurea for Blast and Impact Protection: A Review

“…High-strength and high-modulus polymer composites are produced by reinforcing the polymer matrix with high-strength and high-modulus fibers, the reinforcing fibers are employed to increase the strength and stiffness of the material, and the load is transferred to the fibers via the viscoelastic displacement of the matrix under stress [74]. The reinforcing fibers that are commonly used for enhancing performance are glass fiber (GF) [20,39,[70][71][72][73]75], basalt fiber (BF) [22,23,76,77] and carbon fiber (CF) [78][79][80][81]. GF are of two types: chopped glass fiber and milled glass fiber (MG), of which MG is mostly used as reinforcing and filling media in plastic composites, adhesives and coatings.…”

Numerical Analysis of EOD Helmet under Blast Load Events Using Human Head Model

“…Tse et al [16] analyzed numerically the performance of face shields of a polycarbonate-aerogel composite with ACH helmet subjected to different blast loadings. The use of aerogel showed better protection capability than the classical polycarbonate face shields.…”