High-fogging is widely used to rapidly increase the power outputs of stationary gas turbines. Therefore, water droplets are injected into the inflow air, and a considerable number enter the compressor. Within this paper, the primary process of droplet evaporation is investigated closely. A short discussion about the influential parameters ascribes a major significance to the slip velocity between ambient gas flow and droplets. Hence, experimental results from a transonic compressor cascade are shown to evaluate the conditions in real high-fogging applications. The measured parameter range is used for direct numerical simulations to extract evaporation rates depending on inflow conditions and relative humidity of the air flow. Finally, an applicable correlation for the Sherwood number in the form of $Sh(R{e}^{1/2}S{c}^{1/3})$ is suggested.

Shear-driven liquid rivulet flow on a horizontal plate is experimentally investigated. In contrast to publications found in the literature, a two-side view on the rivulet is used to simultaneously capture the side and top view. This enables more accurate measurements of the rivulet dimensions and the subsequent calculation of derived quantities. Throughout the experimental test campaign, the ambient gas velocity and the liquid mass flux are altered. In a first qualitative analysis, the occurring rivulet flow regimes are classified and mapped depending on the gas Reynolds number ReG and the rivulet Weber number We. Furthermore, the goal is to quantify the correlation between characteristic rivulet dimensions and the ambient conditions, with a focus on straight and surging rivulets. The quantitative analysis results in an implicit correlation for the rivulet width and height depending solely on the ambient gas velocity and the rivulet mass flow. The investigation of the rivulet wavelength reveals an analogous dependence on the ambient gas velocity. However, the dependence on the rivulet mass flow changes depending on the rivulet flow regimes.

Two-phase flow in gas turbine compressors occurs, for example, at heavy rain flight condition or at high-fogging in stationary gas turbines. The liquid dynamic processes are independent of the application. An overview on the processes and their approach in literature is given. The focus of this study lies on the experimental investigation of the trailing edge disintegration. In the experiments, shadowgraphy is used to observe the disintegration of a single liquid rivulet with constant liquid mass flow rate at the edge of a thin plate at different air flow velocities. A two side view enables calculating droplet characteristics with high accuracy. The results show the asymptotic behavior of the ejected mean droplet diameters and the disintegration period. Furthermore, it gives a detailed insight into the droplet diameter distribution and the spreading of the droplets perpendicular to the air flow.