Comparison of strength assessment methods for bolted connections
Backgroud:
Wind turbines are built up using large structural components, like blades, bearings, main shaft, frame, tower sections etc. These components are generally connected by means of pre tensioned bolts. Just like the components also the bolt connections need to be assessed on their strength to bear fatigue and extreme loads in order to pass certification. For assessing these bolted connections various methods are available, ranging from hand calculations to very detailed FEM models with matching post processing. The amount of required effort and obtained detail varies significantly from one method to the other.
Purpose:
The aim of this project is to compare various methods of bolt strength assessment. Depending on the outcome the current assessment methods may be updated to a new standard.
Outline:
For one or more bolt connections the following steps are executed:
- Hand calculation of bolt strength, for fatigue and ultimate loads
- Building different FEM models
- Perform required FEM calculations and post processing results
- Fatigue and ultimate strength analysis using different methods and in house developed software
- Comparison of method and results
- Recommendations for adaptation of current methods.
- Reporting in our Good Working Practice documentation.
Preferably you study a bachelor or master in Mechanical Engineering. The actual content of the project can be adjusted to your level. Knowledge of finite element method (FEM) and Ansys is preferred. You will work amongst a team of engineers that can benefit from your contribution. Some of these engineers will be involved in this project for assistance and feedback. You may also contribute in the adaptation of the in house software to facilitate new methods, but programming software is outside this project scope.
Type of project:
Traineeship, bachelor level or graduation, master level.
Coordinator / for more information on the subject:
Ir. Theo de Gruiter, Chief engineer, +31 (53) 4821 433, t.degruiter@mecal.eu
Product group and location:
Wind Energy, Turbine Development, Enschede
To apply for the project:
Mr Dick van Haare, Recruitment, +31 (53) 4821 400, d.vanhaare@mecal.eu