Complex fluid flow structures in macro and micro systems are extensively analyzed using the Computational Fluid Dynamics (CFD). In order to increase the accuracy of computational simulations, there are numerous challenges that result in demanding numerical calculations that are most commonly performed on a supercomputer in order to obtain the results in reasonable time with optimal CFD application.

Due to the new demands for flexible production of electricity in hydro power plants, hydraulic turbine runner blade geometry will be analysed, using supercomputer, to see the impact on increasement of water turbine efficiency in a wide operating range. Impact on the diffuser vortex intensity reduction will also be analyzed.

In the turbine intake the impact of the protective trashrack, which creates inevitable head losses and often cause the injuries of the fish that fail to escape it , will be analyzed. By applying CFD, optimization of bar shapes and configurations of trashrack will be carried out to minimize hydraulic losses and to redirect fish to by-pass structures.

Parametric rolling is caused by an uncommon combination of natural and design parameters which can cause deck load loss in new types of container ships. For the efficient solution of such a complex problem, "Virtual Towing Tank" was developed as a substitute for model testing, allowing to observe the phenomenon and make hull design changes on time. Further research will focus on finding an optimal numerical model for the prediction on the parametric rolling occurrance more quickly and accurately.

The multidisciplinary approach to fluid dynamics research has affirmed numerical simulations usage in biomedicine. Endodontic irrigation research is of exceptional scientific and clinical importance. CFD irrigation analysis modeled with the use of micro CT scans of endodontic areas, as well as the research of activated irrigations, would deepen scientific findings applicable in clinical practice.