A Fluid-Structure Coupled Computational Model for the Certification of Shock-Resistant Elastomer Coatings
Abstract
The goal of this three-year research project is to develop a high-fidelity computational model capable of predicting the dynamic response of bilayer elastomer coating ~ substrate structures to underwater explosion (UNDEX), thereby establishing an accurate, simulation-based platform for certifying shock-resistant elastomer coatings for various naval applications. To achieve this goal,the basic approach of this project is to develop and validate a three-dimensional (3D), CFD (computational fluid dynamics) ~ CSD (computational solid dynamics) coupled computational model, basing on the FIVER framework recently developed by the PI and collaborators. A unique feature of FIVER is that it couples a compressible multiphase CFD solver with a nonlinear finiteelement CSD solver using a physics-based embedded boundary method. Therefore, it is particularly suitable for shock-dominated fluid-structure interaction problems involving complex wave propagation/attenuation, large deformation, and fracture. Specifically, this project will focus on investigating shock-induced collapse of thin-walled aluminum cylinders with elastomer coating, and elucidating the effects of the coating on the onset and the dynamic process of the collapse. The project will start with implementing recent viscoelastic/viscoplastic constitutive models of shockresistant elastomers that are particularly designed to capture the materials~ extraordinary propertiesunder high pressure, high strain-rate loading. Next, the computational model will be applied to simulate several academic benchmark problems and underwater implosion experiments, thereby verifying the accuracy of the solver for handling non-conservative follower forces and validating its capability for predicting dynamic implosive collapses. After verification and validation, a comprehensive parametric study will be conducted to elucidate the effects of the coating materialunder UNDEX loading, therefore establishing the causal relationship of (a) the loading condition, (b) the resulting shock transmission, reflection and attenuation, (c) the deformation of the structure, and ultimately (d) the performance of the coating for mitigating structural failure. Furthermore, a3D extended finite element method (XFEM) will be implemented to simulate shock-induced fracture and coating delamination, and to further investigate the feasibility of arresting collapse and cracking through local modification of coating.This project is closely aligned with the Operational Endurance priority of the 2017 Naval Research and Development Framework. Shock waves from UNDEX is a major threat to Navy ships, submarines, unmanned underwater vehicles (UUVs), and personnel in modern warfare and terrorist attacks. Recent studies supported by ONR have identified a class of elastomeric copolymers as promising shock-resistant coating materials. This project will bridge the currentcritical knowledge gap between the unique properties of these materials and their shock-mitigation performance in real-world naval applications. The computational model developed in this project will be delivered to ONR and made available to the defense acquisition community. The project will potentially lead to a reliable computational software for designing and certifying shockresistant coatings, thereby significantly reducing the high cost and risk associated with shock trials.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 24, 2019
- Source ID
- N000141912102
Entities
People
- Kevin G. Wang
Organizations
- Office of Naval Research
- United States Navy
- Virginia Tech