Energy efficiency improvement of submersible pumps using in barind area of Bangladesh.

Abstract Due to the fluctuating nature of ground water level, it becomes impossible to operate submersible pumps in the designed head and discharge. As a result, these pumps are running at lower efficiency (about 18% to 35%) compared to standard laboratory efficiency 64% around the year. This deficiency in efficiencies causes huge consumption of energy and corresponding costs. The total operating head of the submersible pumps includes a parameter known as "drawdown" which is the difference between pumping level and static water level. The drawdown parameter has a significant effect on pump performance. In the present work, the drawdown characteristics of a 3HP submersible pump have been studied in laboratory scale by varying the filter length and well diameter. The pump characteristic curves are plotted and compared for various well and filter arrangement. The maximum pump efficiency was 38% in 0.15m well diameter and 0.90 m filter length with 42 m head and discharge about 138 liter/min. It has observed that the amount of drawdown decreases significantly with increasing well diameter and filter length. However, beyond 0.90 m filter length, the drawdown starts decreasing and energy consumption increases. A specific arrangement of pump and well is suggested which will provide maximum efficiency under specific operating condition. A mathematical relation has also been developed by multiple regression model to account the effect of filter length and well diameter in submersible pump performance. [ABSTRACT FROM AUTHOR]