Volume No. 6 Issue No.: 3A Page No.: 863-868 Jan-Mar 12

 

NUMERICAL STUDIES ON EFFECTS OF BLADE NUMBER VARIATIONS ON PERFORMANCE OF CENTRIFUGAL PUMPS AT 2500 RPM

 

K.M. Pandey*, A.P. Singh1 and Sujoy Chakraborty2

1. Department of Mechanical Engineering, N.I.T. Silchar, Assam, (INDIA)
2. Department of Production Engineering, N.I.T. Agartala, Tripura, (INDIA)

 

Received on : November 25, 2011

 

ABSTRACT

 

Centrifugal pumps are used extensively for hydraulic transportation of liquids over short to medium distance through pipelines where the requirements of head and discharge are moderate. The pump design is facilitated by the development of computational fluid dynamics and the complex internal flows in water pump impellers can be well predicted. Various parameters affect the pump performance. The impeller outlet diameter, the blade angle and the blade number are the most critical. In this study, the performance of impellers with the same outlet diameter having different blade numbers is thoroughly evaluated. The investigation focuses mostly on the performance characteristics of pump. At present, the influence of blade number on inner flow field and the char- acteristics of centrifugal pump has not been understood completely. Therefore, the methods of numerical simu- lation and experimental verification are used to investigate the effects of blade number on flow field and per- formance of a centrifugal pump. The use of numerical analysis tools allows us to obtain data in positions where experimentation is not possible. The inner flow fields and characteristics of centrifugal pump with different blade number are simulated and predicted in steady condition by using Ansys Fluent software. The standard kε turbulence model and SIMPLEC algorithm applied to solve the RANS equations. The simulation is steady and moving reference frame is applied to take into account the impeller-volute interaction. For each impeller, static pressure distribution, total pressure distribution and incompressible flow characteristics of centrifugal pump are discussed. In this paper, the numerical analysis has been carried out at 2500 r.p.m and the changes in head as well as efficiencies have been investigated. With the increase of blade number, the head and static pressure of the model increases and total pressure too, but the variable regulation of efficiency are complicated, but there are optimum values of blade number for each one.

 

Keywords : Centrifugal pump, Blade number, CFD, Pressure distribution, Numerical analysis

 

 

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