Development of a Software Tool to Analyze Personal Flotation Devices
Abstract
A computer program, WAter Forces Analysis Capability (WAFAC) , was developed to analyze forces acting on bodies in water. The WAFAC model computes buoyancy, wave-excitation, added-mass, and drag forces acting on a system of linked bodies in water. The bodies are assumed to be rigid ellipsoids. Sea states can be approximated by the superposition of up to ten regular waves or by a single regular wave of amplitude equal to the 'significant wave height' and frequency based on the Pierson-Moskovitz spectrum for fully developed ocean waves. The WAFAC model is structured to compute components of force and moment due to buoyancy, wave-excitation, added-mass, and drag using separate modules. During development, each module was tested to assess the accuracy of the results predicted. The resultant water force and moment acting on each ellipsoid in the system of linked bodies is determined by the vector sum of the individual force components. The WAFAC model was incorporated into the Articulated Total Body (ATB) model to analyze the dynamics of the system of linked bodies subject to the water forces and moments. To validate the model, simple geometries such as spheres and ellipsoids were modeled and the results compared with analytical solutions. Bioengineering, Biomechanics, Buoyancy, Computerized simulation dynamics, Mathematical model, Personal flotation devices.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1992
- Accession Number
- ADA273706
Entities
People
- D. P. Weerappuli
- L. Obergefell
- N. Rangarajan
- T. Shams
- Y. M. Zhao