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The experimental results of wet steam flow in the blade channel of flat nozzle blade cascade have been considered in the paper. The aim of this work is to study the motion of liquid droplets inside the inter-blade channel. Experimental studies were performed on installation circuit of wet steam. In order to obtain velocity fields of droplets in investigated channel, the laser diagnostics system was used. It carries out the cross-correlation method-particle tracking velocimetry. Numerical simulation of wet steam flow in studied channel was performed. According to the obtained data, the main features of the droplets motion in the blade channel have been revealed. Basic droplets streams and the sources of their appearance have been determined. The process of deposition and breakdown of the droplets on the surface of the blades have been studied. It is shown that reflected region of droplets (''fountain'') is formed around the leading edge. The experimental data were compared with the results of numerical simulation of the droplets motion in the flat nozzle blade cascade.

The results of experimental studies of supersonic steam flow downstream the flat turbine nozzle blade cascade has been considered. The investigations were carried out in a broad range of steam initial conditions (superheated, dry saturated) and isentropic Mach (M1t) number downstream the object of study. The schlieren method was used to obtain the visual information about shock waves structure. The flow parameters oscillations were measured by pressure transducers situated at different locations downstream the object of study. It is shown that the occurrence of condensing shock at conditions of superheated steam upstream the nozzle blade cascade leads to the sufficient unsteadiness of shock waves system. This is due to the complex relationship between the boundary layer and a shock wave system. With changing of initial steam conditions the rearrangement of static pressure frequency spectra is observed.

The results of the experimental studies of wet-steam flow with injection of hot steam from the slot downstream of the turbine flat stator blade cascade have been considered. In the studied profile there is one injection slot on the pressure side surface near the trailing edge. The investigations have been carried out at different initial wetness of the main flow and different injected steam temperatures at the constant pressure of injection. Laser diagnostic system "POLIS" which includes PIV method has been used to analyze the influence of heating steam injection on the characteristics of the liquid phase downstream of the blade trailing edge. It is shown a heating steam injection has an effect on the vector fields of coarse droplets downstream of the blade cascade. At the same time kinetic characteristics of coarse droplets downstream of the stator blades cascade are independent of the temperature of the injected steam. Exit angles of coarse droplets obtained at the different distance from the trailing edge are presented.