A centrifugal pump with an overall efficiency of 0.56 rotates at 1650 rpm. The flow is purely radial at the inlet of the rotor. The pump has the following characteristics: Flow rate Q = 72 L/s Inlet diameter D1 = 90 mm Outlet diameter D2 = 280 mm Head H = 25m Width at the inlet b1 =20 mm Width at the outlet b2 = 18 mm Leakage q = 2 L/s Mechanical loss Pm = 1.41 kW Blade angle at the outlet β2 = 35 ͦ The water density ?=998 ??/m^3 Atmospheric pressure 101 kPa 1) Draw the velocity triangles at the inlet and the exit of the impeller. 2) Determine the magnitude of the absolute velocity of the flow (?) and the impeller velocity (U) at the inlet and outlet 3) Determine the blade angle at the inlet. 4) Determine the hydraulic, mechanical and volumetric efficiencies. 5) Determine the minimum number of blades required for the slip to not exceed 0.9. 6) Determine the static pressure difference (P2-P1) through the impeller by using Bernoulli equation. 7) Determine the available NPSH if the pump is placed 2m above the free surface of the tank and the vapor pressure is ?=2.43 ???. !!!!!!!!! I ONLY NEED PART 4,5,6 and 7 PLEASEEEEEE
A centrifugal pump with an overall efficiency of 0.56 rotates at 1650 rpm. The flow is purely radial
at the inlet of the rotor. The pump has the following characteristics:
Flow rate Q = 72 L/s
Inlet diameter D1 = 90 mm
Outlet diameter D2 = 280 mm
Head H = 25m
Width at the inlet b1 =20 mm
Width at the outlet b2 = 18 mm
Leakage q = 2 L/s
Blade angle at the outlet β2 = 35
ͦ
The water density ?=998 ??/m^3
Atmospheric pressure 101 kPa
1) Draw the velocity triangles at the inlet and the exit of the impeller.
2) Determine the magnitude of the absolute velocity of the flow (?) and the impeller velocity
(U) at the inlet and outlet
3) Determine the blade angle at the inlet.
4) Determine the hydraulic, mechanical and volumetric efficiencies.
5) Determine the minimum number of blades required for the slip to not exceed 0.9.
6) Determine the static pressure difference (P2-P1) through the impeller by using Bernoulli
equation.
7) Determine the available NPSH if the pump is placed 2m above the free surface of the tank
and the vapor pressure is ?=2.43 ???.
!!!!!!!!! I ONLY NEED PART 4,5,6 and 7 PLEASEEEEEE
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