Performance Analysis on Flow Through S Shaped Diffusers
Keywords:Pressure recovery coefficient;, Pressure recovery efficiency;, Diffuser;, Reynolds number
Many times due to space limitations it is necessary to decelerate and turn fluid simultaneously. For such requirement curved diffusers are being used. Five S shaped diffusers of turning angle 120o were fabricated. The area ratio was 2.5, 3.5, 4.5, 5.5 and 6.5. The pressure on the outer wall is more than that on the inner wall in the first curvature and less in the second curvature. Variation in actual pressure recovery coefficient (Cp) and pressure recovery efficiency (η) is not very much within the range of Reynolds number tested for a particular diffuser. As area ratio increases value of Cp and η also increases. The optimum area ratio for 120o diffuser is 4.5.
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