Energy efficient journal bearings lubricated by environmentally adapted oils
Bearings supporting rotating shafts are an important machine component that has a strong influence on the overall efficiency and reliability of power installations. Let us consider a steam turbine as an example.
For a 100MW steam turbine power loss in the bearings accounts for 0.4 % or 400 kW. If the power loss is reduced by 50 % an additional power of 200 kW can be produced. Considering the number of steam turbines used worldwide in the nuclear and solar power stations, the bearing efficiency improvement would lead to a significant saving of energy.There are several ways the bearing can be optimized for the specific task. In the project we investigate the influence of the environmentally adapted lubricants and new materials applied to the bearings. While the main goal is to achieve 50% power loss reduction, we also investigate an influence of modern materials on other bearing characteristics, like maximum oil temperature, minimum oil film thickness and bearing stability.
The advanced numerical model is developed and used for the bearing analysis. Test rig experimental data is used for the model calibration and verification. Numerical analysis shows that by applying new environmentally adapted lubricants and polymer materials in bearing design it is possible to
- improved environmental performance
- improved dynamic characteristics
- improved steady state characte ristics with more than 50% lower power loss