Face shield design against blast‐induced head injuries. (31st May 2017)

• Record Type: Journal Article
• Authors: Tan, Long Bin; Tse, Kwong Ming; Tan, Yuan Hong; Sapingi, Mohamad Ali Bin; Tan, Vincent Beng Chye; Lee, Heow Pueh
• Is Part Of: International journal for numerical methods in biomedical engineering. Volume 33:Number 12(2017:Dec.)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-05-31
• Subjects: aerogel -- coupled‐Eulerian‐Lagrangian (CEL) -- fluid‐structure‐interaction (FSI) -- head model -- helmet -- traumatic brain injury (TBI); Biomedical engineering -- Periodicals; Imaging systems in medicine -- Periodicals; Numerical analysis -- Periodicals; Engineering mathematics -- Periodicals; 610.28
• DOI: 10.1002/cnm.2884
• Languages: English
• ISSNs: 2040-7939

Abstract

Abstract: Blast‐induced traumatic brain injury has been on the rise in recent years because of the increasing use of improvised explosive devices in conflict zones. Our study investigates the response of a helmeted human head subjected to a blast of 1 atm peak overpressure, for cases with and without a standard polycarbonate (PC) face shield and for face shields comprising of composite PC and aerogel materials and with lateral edge extension. The novel introduction of aerogel into the laminate face shield is explored and its wave‐structure interaction mechanics and performance in blast mitigation is analysed. Our numerical results show that the face shield prevented direct exposure of the blast wave to the face and help delays the transmission of the blast to reduce the intracranial pressures (ICPs) at the parietal lobe. However, the blast wave can diffract and enter the midface region at the bottom and side edges of the face shield, resulting in traumatic brain injury. This suggests that the bottom and sides of the face shield are important regions to focus on to reduce wave ingress. The laminated PC/aerogel/PC face shield yielded higher peak positive and negative ICPs at the frontal lobe, than the original PC one. For the occipital and temporal brain regions, the laminated face shield performed better than the original. The composite face shield with extended edges reduced ICP at the temporal lobe but increases ICP significantly at the parietal lobe, which suggests that a greater coverage may not lead to better mitigating effects. Abstract : The novel inclusion of aerogel into the laminated face shield and its effectiveness against blast was explored due to its transparency and excellent shock‐absorbing capability. In general, a face shield gives better protection against blast, with a laminated face shield performing better than the conventional polycarbonate face shield. A face shield with extended side edges may not lead to better mitigating effects due to wave ingress effect at the edges. All face shields reduced air pressures significantly at the eyes.