Secondary flow remains a challenging task for both the researchers who pursue diligently their efforts to develop an improved understanding of the mechanisms of loss production and for the designers who endeavor to minimize the impact of losses on turbine performance by controlling the secondary flow and by reducing their interference with the main flow. As an extension to control secondary flows and losses reduction in turbine blades, this work introduces an experimental investigation which was carried out to establish the effect of endwall injected air on a turbine blade losses by different air jets location through flow channel between two consecutives blades and also with different inlet air flow speed at subsonic flow conditions through the blade cascade. Tests were conducted by using a linear cascade of turbine blades. The cascade was fixed on a wind tunnel and working as air flow supply. Measurements of wall static pressure on the pressure and suction sides of the blades, the total pressure at flow passage exit section and determination of flow loss for blade profiles are presented. The results showed readings changes due to the alteration of location and speed of endwall air jets. It is found that, the best results were recorded in the case of endwall air jets location at suction side of the tested blade with M = 0.12. Air jets successfully diverts the path of the passage vortex and decreases its effect on the suction side blade by creating higher static pressure on pressure side (10.2% higher in blade pressure loading than on case without air injection application) and preventing boundary layer separation at suction side and also This modification has a significant effect to create a homogeneous pressure distribution through blade chordwise and hence reducing the possibilities of flow vortices existence then reducing the undesirable effects of secondary flow.

Developing accurate models for pressure drop in slurry pipelines is one of the most important challenges of researchers around the world. Pressure drop is one of the most important technical parameters to be ev aluated by the designer of pipeline slurry transportation system. Also it is the parameter which dictates the selection of pump capacity. The properties of slurries mainly depend on the tendency of the particles to settle out from the carrying liquid. The extent to which the particles will be free to settle in horizontal flow depends on the terminal velocity, the turbulence and particleparticle interaction. Physical models for the prediction of the pressure drop, flow regime, and specific energy consumption are presented. Several studies for pressure drop prediction in slurry flow are available in literature. The comparison between the proposed correlations with the experimental data of the settling slurries is satisfactory. Since the decrease of the specific power consumption and increase overall the transport system efficiency, the carrying capacity should be increased. The experimental investigations were performed on three different sorts of sand solids to satisfy the economic advantage by adjusting the particle size. The experiments were conducted in 26.8 mm inner diameter horizontal pipe on three sizes of sand particles of which mean diameter are 0.2 mm (fine), 0.7 mm (medium) and 1.4 mm (coarse). Flow velocity was up to 7 m/s and overall concentration up to 33% by volume for each velocity. The effect of slurry velocity and particle concentration on the slurry flow behaviour and pressure drop in the turbulent regime was evaluated.

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