INVESTIGATION OF STRESSES ON IMPELLER BLADES BY COMPUTATIONAL FLUID DYNAMICS (CFD) ANALYSES

Öz

This paper discusses how stresses on the impeller blades are affected by the temperature, pressure, and blade thicknesses. During operation, the impeller experiences many kinds of stresses caused by thermal, fluid, and mechanical effect. These may deform the impeller blades if the stresses are too high. The impeller used in this case study was provided by HAUS Centrifuge Technologies and this impeller was damaged in the field during the operation. Six different blade thicknesses were structurally analyzed, and the Von-Mises stresses were compared to the impeller material yield strength. The impeller with the least stress was then selected to perform the FSI analysis. It was then manufactured, and a performance test was performed using the ISO 5389 in a test facility. From the CFD results, it was observed that the polytropic efficiency and the discharge temperature was affected by the change in blade thickness. It was concluded that an increase in blade thickness reduces the stresses acting on the blade.

Anahtar Kelimeler

• Blade thickness
• CFD
• FSI
• Impeller
• Von-Mises stress
• Polytropic efficiency

Kaynakça

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