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-

F=

gV =

V=

zA

V= z A

p = F

A

zA A=

z

where F : force due to fluid weight

V : volume

g : acceleration due to gravity (32.17 ft/s2)

: fluid density in pound mass per unit volume

: fluid density in pound force per unit volume

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POTENTIAL SPECIFIC ENERGY

Potential specific energy = z

Figure 1-3 Potential specific energy provided by the difference in elevation of fluid particles.







KINETIC SPECIFIC ENERGY

Kinetic specific energy = v2/2g

Figure 1-4 Kinetic specific energy provided by moving fluid particles.

PRESSURE SPECIFIC ENERGY

Pressure specific energy= p/

Figure 1-5 Pressure specific energy provided by the weight of a fluid column.







Z

(p/

v2/g

Figure 1-6 The relationship between pressure, elevation and velocity.





-

Figure 1-7 The relationship between pressure and elevation.

Figure 1-8 Pressure variation due to elevation in a real system.







Figure 1-9 The relationship between pressure and velocity.

Figure 1-10 The 3 forms of energy in a fluid system, potential, kinetic and pressure.







Emvmgzmgp/

mvE

mg

EQ

Figure 1-11 A typical pumping system.





Figure 1-13 The difference in pressure due to fluid friction.

Figure 1-14 The effect of equipment in a system.

c







A

VCV

Figure 1-15 Various systems with varying output velocities.

-

Figure 1-16 The difference in elevation between suction and discharge tank.







Figure 1-17 Pressurized suction and discharge tanks.

Figure 1-18 Ouch.







Figure 1-19 The pressure distribution in a static system.

Figure 1-20 Creating negative pressure.







Figure 1-21a Water suspended from an open tube 34 feet high.

Figure 1-21b Difference in pressure in a water column suspended from an open tube 34 feet high.





Figure 1-22 Absolute vs. relative pressure scales.

Figure 1-23 A siphon as a rope.

Figure 1-24 Water suspended in an open tube.









SG

SGSG

gcD



Figure 4-1 Using a spinning bottle to demonstrate centrifugal force.

Figure 4-2 Typical pump capacity coverage chart.







Figure 4-3 Typical pump performance curve.

Ashut-offB

run out

Figure 4-4 Typical performance curve for a specific impeller diameter.

BEP







testing

Figure 4-5 Coverage area of horsepower curves.

NPSHNPSH

NPSH





Figure 4-6 N.P.S.H required curves.

where DOP : impeller diameter required; HOP : pump total head at the operating point; H9 : pump total head at the intersection of the 9 impeller curve and flow rate; H91/2 : pump total head at the intersection of the 9 1/2 impeller curve and the flow rate.

BEP



BEP

Figure 4-8 Desirable pump selection area.







Figure 4-9 Superposition of system curve and pump performance curve.

H (q) = H (q) + H (q) + H (q) + HTS

USGPM



Figure 4-10 Location of operating point in example 2.1.

Figure 4-11 Starting the pump with discharge valve closed.

USGPM

hammering







Figure 4-12 Starting the pump with discharge valve open.

a

Figure 4-13 Location of capacity factor.

C

aC

a

C







C

B

d

b

aC

BEP

Figure 4-14 The forces on the impeller.





BEP

BEP

Figure 4-15 Variation on the magnitude of the radial force on the impeller according to the position of the operating point with respect to the B.E.P.(reprinted with permission of McGrawHill).

BEP

BEPrun-outNPSH

BEP



BEP

Figure 4-16 Variation in the level of vibration at the operating point vs. the position of the B.E.P.(reprinted with permission of the Goulds pump company).

Figure 4-17 Internal recirculation at low flow (reprinted with permission of McGraw-Hill).







shut-off head:

shut-off

Figure 4-18 Discharge pipe coming from a higher elevation into the discharge tank.

Figure 4-19 Location of pump shut-off head on the performance curve.







P = pP q

where pP is the difference in pressure at the inlet and the outlet of the pump, and q

the flow rate.

AFFINITY LAWS

4.9

PnDH



Figure 4-20 Limitation on the use of the affinity laws.





AB

BB

A

nD

D



spacerframe

BEP

shut-off

PUMP SYSTEM ANALYSIS AND SIZING BY JACQUES CHAURETTE p. eng.

CMField training

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