الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Flow in curved diffusers is characterized by the presence of vortices or secondary motion due to curvature effects including the imbalance between radial pressure gradient and centrifugal forces. At the first half of the diffuser the flow is seen to accelerate on convex wall, to balance the slower flow on the concave wall as a result of higher pressure due to centrifugal forces there. At the second half the presence of the adverse pressure gradient forces the growth of the boundary layer along the convex wall causing flow separation and the maximum velocity is shifted to the concave wall. In this study 3D turbulent flow inside 180-curved diffuser was investigated experimentally by a five-hole pressure probe. The three average velocity components, static and total pressures were measured as well as the wall static pressure in the mid-span between the two parallel walls at the convex and concave wall. Contours of the third velocity component show the secondary motion clearly results from the movement of fluid from convex to concave wall and reverse, the maximum transverse velocity is about 20% of inlet mean velocity as a result of low aspect ratio of the diffuser exit, while the overall pressure recovery achieved was 25.6% of the inlet dynamic pressure due to separation and recirculation occurred at the convex wall.