Method of initializing bolt pretension in a finite element analysis
US8069017B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 25, 2008 |
| Grant date | Nov 29, 2011 |
| Priority date | — |
| Expiry date | Aug 2, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F30/23
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In one aspect of the invention, each bolt is modeled using a beam element in a FEA model. To apply desired pretension to one or more bolts, at least one pretension-versus-time curve is specified. Each pretension-versus-time curve includes ramp portion, desired pretension portion and optional unloading portion. Duration of the pretension-versus-time curve generally covers first 0.5-1% of total simulation time of a car crashworthiness analysis. Ramp portion starts from zero to desired pretension in a substantially linear manner, and hence being configured for applying desired pretension to a bolt gradually with smaller increments. Desired pretension portion is configured for ensuring the desired pretension can actually be applied to the beam element during an initialization process—a series of quasi-static analyses. Since the method is independent of the deformation of the beam, the method completely avoids the need to iteratively determine an axial strain or displacement that gives the desired pretension.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.