title: Conventional and complex modal analyses of a finite element model of human head and neck.
abstract: This study employs both the traditional and the complex modal analyses of a detailed finite element model of human head-neck system to determine modal responses in terms of resonant frequencies and mode shapes. It compares both modal responses without ignoring mode shapes, and these results are reasonably in agreement with the literature. Increasing displacement contour loops within the brain in higher frequency modes probably exhibits the shearing and twisting modes of the brain. Additional and rarely reported modal responses such as 'mastication' mode of the mandible and flipping mode of nasal lateral cartilages are identified. This suggests a need for detailed modelling to identify all the additional frequencies of each individual part. Moreover, it is found that a damping factor of above 0.2 has amplifying effect in reducing higher frequency modes, while a diminishing effect in lowering peak biomechanical responses, indicating the importance of identifying the appropriate optimised damping factor.
authors: a Department of Mechanical Engineering , National University of Singapore , 9 Engineering Drive 1, Singapore 117576 , Singapore.
authors: Kwong Ming
authors: KM
authors: Tse
authors: Long Bin
authors: LB
authors: Tan
authors: Siak Piang
authors: SP
authors: Lim
authors: Heow Pueh
authors: HP
authors: Lee
keywords: complex frequency; damping factor; finite element; head–neck; mode shape; natural frequency