ABSTRACT

The performance of a radial split axial pull-out barrel casing multistage centrifugal pump was quantified and optimized using response surface analysis for a more efficient pump operation. The factors evaluated were the impeller discharge diameter (D7 ), p mp suction pipe diameter (d1) impeller blade length (lb) impeller blade discharge angle (82), radial tip clearance (t) and impeller blade discharge width (B2) while the pump efficiency (ri), flow rate (Q), head (H) and speed (N) were the responses. Multi-responsemulti-factor mathematical models were estimated which were visualized in 3-D response surface and 2-D contour plots generated using MATLAB, and fmal numerical optimization was conducted using the desirability function approach provided by MINITAB to determine the optimal settings of the. responses and factors after the adequacy of the models to approximate the measured data well had been established at 95% confidence interval. The result showed that the pump had an optima efficiency, flow rate, head and speed of 78.37%, 191.61m3 /h, 967.63m and 2500rpm respectively at optimal impeller exit diameter, pump suction pipe diameter, blade length, blade discharge angle, radial tip clearance and blade discharge width of 366mm, 417mm 70mm, 39°, 36 mm and 64mm respectively. It was established that all the factors affected all the responses sigriifi antly. So it was concluded that reducing the impeller discharge diameter, impeller blade length tind impeller blade discharge angle by 8.5%, 53.3% and 22% respectively and increasing the, pimp suction pipe diameter, impeller radial tip clearance and impeller discharge width by 19%, 64% and 28% respectively will increase the efficiency and flow rate of the pump by 18% and 21% respectively, and reduce its head and speed by 3.3% and 30% respectively. This also reducec the energy consumption by 1 1. 20- /0.