Mykola Ivanovych Sotnyk

Numerical Study of Outlet Blade Angle Effect on Impeller Characteristics of Double Entry Centrifugal Pump

The characteristics of pump performance are depended strongly on the impeller geometry. Changes in some impeller geometric parameter can improve pump performance. It is well known that outlet blade angle is one of those parameters, which has significant effect on the impeller work characteristics. This work is connected with the effect of blade outlet angle changes on the performance of double entry centrifugal pump impeller. This process is investigated via Ansys computational fluid dynamics (CFD) software. CFD method can predict well the complex internal flows in centrifugal impellers. The present paper describes the simulation of four impeller working process. The outlet blade angle was changed from 26° to 32° while all other geometrical impeller parameters were kept constant. The head-flow rate, hydraulic efficiency-flow rate and shaft power-flow rate curves are compared and discussed for each impeller. The obtained results show that even insignificant changes of the blade outlet angle effect on the impeller performance.

Head pulsations in a centrifugal pump

This article investigated the factors, which affect to the character of the head pulsations of a centrifugal pump. We investigated the dependence of the shape and depth of these pulsations from the operation mode of the pump. Was determined, that the head pulsations at the outlet of the impeller (pulsations on the blade passing frequency) cause head pulsations at the outlet of the pump, that have the same frequency, but differ in shape and depth. These pulsations depend on the design features of the flow-through part of the pump (from the ratio of hydraulic losses on the friction and losses on the vortex formation). A feature of the researches that were conducted is also the using of not only hydraulic but also electric modeling methods. It allows determining the values of the components of hydraulic losses.

Monitoring of Pumping Unit Operation in Indicators of Energy Efficiency of its Work

The influence of pumping unit’s elements on the overall energyefficiency of its work is viewed in the article. The areas of pumping unit’s operation effectiveness are identified and evaluated within the field of his QH characteristics and efficiency of its use in real technological process. The methodology of pumping unit’s operation evaluation in different modes through indicators of unit electrical energy consumption is developed.

Modeling of Centrifugal Pumps Operating Modes

Research of centrifugal pumps’ workflow through their modeling is made. The methods of modeling such processes are viewed: by traditional numerical method and by proposed purely electrical methods of modeling. By comparing modeling results with test results the adequacy of modeling by purely electrical methods is proved.