8/18/2019 Presentasi Mekanika Fluida

1/7

Same level

Pump

1 2

3”

2000ft 3in sch 40 pipe

• Two reservoirs are connected by 2000ft, 3in sch 40 pipe

•e want to pump 200!al"min water from reservoir 1 to 2•#evels of reservoirs are same and both open to atmospher•Pipe rou!hness 0$001%

&'200!al"min

1$ Po(2$ )P(

Suction and dischar!e

*'0$001%

Po

)P

P1

8/18/2019 Presentasi Mekanika Fluida

2/7

Steps1$ +pply bernoulis e-uation from point 1 to point

2

.riction

heatin! perunit mass

Pumpwor/

ead pumpability to pumpuids

 "m

8/18/2019 Presentasi Mekanika Fluida

3/7

8/18/2019 Presentasi Mekanika Fluida

4/7

ead the 6raphic

8/18/2019 Presentasi Mekanika Fluida

5/7

.ind .riction #ost.'0$004%

 

∆P

 ρ

=  −F  =  −4 f ∆ x

 D

V 2

2

= −4.0,00482000 ft .(8.68

 ft 

s)

2

2(3.068

12

 ft )

.  lbf .s

2

32.2lbm. ft 

=  −176 ft .lbf  / lbm

=  −524 J  / kg

8/18/2019 Presentasi Mekanika Fluida

6/7

Pressure Riseeducin! the 7ernaullis 8-uation,

 

∆P

 ρ=

−dW a.o

dm

 

∆P =− ρdW a.o.

dm=   −62,3

lbm

 ft 3

 

⎝ ⎜

 

⎠ ⎟  −176

 ft .lbf 

lbm.

 ft 2

144 in 2

 

⎝ ⎜

 

⎠ ⎟

= 76,1lbf 

in2 = 524kPa

8/18/2019 Presentasi Mekanika Fluida

7/7

Mechanical Power Deliveredto the Fluid

 The pump power re-uired is

9f pump is 100: e;cient, power input to the pumpe-uals to this

 

Po =dW a.o.

dt =dW a.o.

dmΜ

 

Μ = 200 gal

min.1min

60s.62,3

lbm

 ft 3 .

  ft 3

7,48gal= 27,8

lbm

s

 

Po =  −176  ft .lbf lbm

.27,8 lbms

.   hp.s550 ft .lbf 

=  −8,90hp = 6,63kW