Anumerical procedure is presented for analysis of pressure pulsations in hydraulic turbines. Results of its use for description of unsteady turbulent flow in the continuous run of a hydraulic turbine are presented. The nu- merical method is adapted for results of modeling of turbulent unsteady flow in the continuous rune of a high-head HPP. The structure of the flow beyond the impeller and its effect on the intensity of unsteady pro- cesses are examined. Results of the analysis are compared with full-scale data. Good agreement is obtained between the computed and experimental results. Capacity regulation in the power system is a critical problem of hydroelectric power plants. When the load varies, the generating sets pass repeatedly through non-standard loading regimes. In such regimes, a significant portion of the swirling remains in the flow after passing through the impel- ler of the hydraulic turbine. Development of vigorous low- frequency hydrodynamic pulsations, which presents a threat to the reliability of turbine structures, is associated with the unsteady nature of the convoluted flow. An increase in operating stability and an increase in the efficiency of the hydraulic machines is impossible without study of the physical mechanisms of the hydrodynamic pro- cesses, among which unstable phenomena associated with formation of large-scale eddy structures play a major role. Some of the mechanisms responsible for generation of flow pulsations is precession of the vortex core that forms beyond the impeller of the hydraulic turbine in under-loaded or over-loaded operating regimes of the hydraulic turbine, when the flow after passing through the hydraulic turbine has suffi- ciently large residual swirl (1 - 2). Precession of the vortex core presents a serious risk to