Porous structures made of metal or biopolymers with a structure similar in shape and mechanical properties to human bone can easily be produced by stereolithographic techniques, e.g. selective laser melting (SLM). Numerical methods, like Finite Element Method (FEM) have great potential in testing new scaffold designs, according to their mechanical properties before manufacturing, i.e. strength or stiffness. An example of such designs are scaffolds used in biomedical applications, like in orthopedics' and mechanical properties of these structures should meet specific requirements. This paper shows how mechanical properties of proposed scaffolds can be estimated with regard to total porosity and pore shape.

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Different systems of direct oil supply have been developed in order to facilitate efficient introduction of fresh lubricant to the oil gap and reduction of churning power loss in tilting pad thrust bearings. Up to now there is no documented application of the supply groove in large thrust bearings used in water power plants. The results of modeling lubricant flow in the lubricating groove of a thrust bearing pad will be presented in the paper. CFD software was used to carry out fluid film calculations. Such analysis makes it possible to modify groove geometry and other parameters and to study their influence on bearing performance. According to the results a remarkable decrease in total power loss due to avoiding churning losses can be observed in the bearing.

Large thrust bearings are highly loaded machine elements and their failures cause serious losses. Start ups and stoppages of the bearing under load are specially critical regimes of operation. Load carrying capacity depends on the profile of the oil gap. In transient states this profile is also changing. In the design of large thrust bearings minimizing thermo-elastic deformations is an important goal, which can be accomplished due to application of advanced models of the bearing. Modeling of transient states becomes even more complex since there is a dynamic development of temperature distribution and deformations. Often hydrostatic jacking systems are also used. It seems to the authors that advanced bearing models are applied only in research and development of the bearings while very simple modeling is applied in on-line analysis of data from monitoring systems. Analysis of the measurement data with the use of more sophisticated models may be helpful in assessment of current bearing status -especially in early warning. Material issues create a separate problem for modeling, being more important nowadays as polymer lined bearings come into use. The models used for polymer lined bearings require realistic treatment of heat exchange and resilience of the bearing surface layer.