81% O O O O 51% 71% 61% Figure below shows the performance curve family of Model 5009 Centrifugal pumps of Taco Pump Inc., running at a fixed speed of N = 1160 rpm. For the pump with the impeller diameter D = 8.625 in., you are asked to determine the best efficiency point (BEP) of the given pump. What is the pump efficiency at BEP? Taco NPSH Model 5009 FI & CI Series 50 L/SEC 5 10 15 20 25 30 35 1160 RPM FEBRUARY 19. 2002 40 45 50 Curve no. 2140 Min. Imp. Dia. 6.75" Size 6 x 5 x 9.0 55 60 12 36 REQUIRED NPSH 9 -27 6 18 40 40 3 FEET DOING KPo HEAD IN FEET 9.25" (235mm) 8.625" 30 (219mm). 20 20 8.00" (203mm) 7.375"H (187mm) 6.75" (171mm). -5 5 68% 77% 79% 79% 75% %09 10 10 CURVES BASED ON CLEAR WATER WITH SPECIFIC GRAVITY OF 1.0 125 1.5HP (1.1KW) 3HP (2.2kw) 2HP(1.5KW) 625 750 375 500 FLOW IN GALLONS PER MINUTE 250 de 7.5HP(5.6KW) 5? de SHP(3.7KW) 2 2 875 1000 4 100 10 -80 8 HEAD IN METERS 40 20 -20 HEAD IN KILOPASCALS