Chapt. 14 (Solved Problems) - philadelphia.edu.jo
42
Dr. Munzer Ebaid Dr. Munzer Ebaid ١ CHAPTER (14) TURBOMACHINARY SOLVED PROBLEMS DR. MUNZER EBAID
Transcript of Chapt. 14 (Solved Problems) - philadelphia.edu.jo
Dr. Munzer Ebaid Dr. Munzer Ebaid ١١
CHAPTER (14)
TURBOMACHINARY
SOLVED PROBLEMS
DR. MUNZER EBAID
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٢
Thrust Coefficient of a propeller:
Power Coefficient of a propeller:
Efficiency of a propeller:
Head Coefficient of an axial Pump:
gnDHCC TH 22
4 ∆==
π
Discharge Coefficient of an axial Pump:
Power Coefficient of an axial Pump :
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٣
)(),(),( feetNPSHgpmQrpmNWhere
Critical value for Cavitation to occur )8500( ≤SSN
Specific speed:
Theoretical Adiabatic Power
with no cooling
Efficiency of a compressor with no water cooling=SHAFTactual
theoComp P
P)(
=η
Specific speed for Turbines
Wind turbine max. theoretical power produced by a
( ) 43
21
NPSHnQNSS =
Dr. Munzer Ebaid Dr. Munzer Ebaid ٤٤
Theoretical Isothermal Power
with cooling
Specific speed for Turbines
Then: Max. Power of the Turbine2
2JVQP ρ=
Power for wind Turbines
Power for Reaction Turbines
Torque for Reaction Turbines
Dr. Munzer Ebaid Dr. Munzer Ebaid ٥٥
PROBLEMS ON
PROPELLERS
Dr. Munzer Ebaid Dr. Munzer Ebaid ٦٦
Fig. (14.2)
Coefficient of ThrustCoefficient of Power
Dr. Munzer Ebaid Dr. Munzer Ebaid ٧٧
Problem (14.1)
305114003 mkgrpmnmD .,, === ρ
00 =V 00 =nDV
From rest
From rest
Dr. Munzer Ebaid Dr. Munzer Ebaid ٨٨
Problem (14.8)
max? ηω At=
Dr. Munzer Ebaid Dr. Munzer Ebaid ٩٩
Problem (14.8)
hkmVmD
402
0 ==
max? ηω At=
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٠١٠
PROBLEMS ON
AXIAL PUMPS
Dr. Munzer Ebaid Dr. Munzer Ebaid ١١١١Dimensionless performance curves for a typical axial-flow pump
Fig. (14.6)
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٢١٢
Performance curves for a typical axial-flow pump
Fig. (14.7)
cmD 6.35=
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٣١٣
Problem (14.11)
?=Q&
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٤١٤
Problem (14.11)
mHcmDrpmnGiven 3401000 =∆== ,,:
?=Q&
gnDHCC TH 22
4 ∆==
π
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٥١٥
Problem (14.15)
?=Q&
?=H?)( =PPower
cmD 6.35=
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٦١٦
Problem (14.15)
)(max,,: ηinDrpmnGiven 201100 ==
?=Q&
?=H ?)( =PPower
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٧١٧
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٨١٨
Problem (14.20)
?)( =PPower
Dr. Munzer Ebaid Dr. Munzer Ebaid ١٩١٩
Problem (14.20)
rpmn 1800=
?)( =PPower
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٠٢٠
PROBLEMS ON
CENTRIFUGAL PUMPS
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢١٢١
Performance curves for a typical centrifugal pump; D = 37.1 cm
Fig. (14.9)
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٢٢٢
Dimensionless performance curves for a typical centrifugal pump from data given in Fig. 14.9
Fig. (14.10)
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٣٢٣Fig. (14.10) Fig. (14.9)
Problem (14.22)
?=Q&fthrpmnGiven 150,1600: =∆=
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٤٢٤
Problem (14.22)
?=Q&
fthrpmnGiven 150,1600: =∆=
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٥٢٥
Problem (14.24)
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٦٢٦
Problem (14.24)
rpsnGiven 30: = Pump Characteristics (Fig.14.9)
104,6.35)( == HeadoffshuttherpsnFor
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٧٢٧
PROBLEMS ON
SPECIFIC SPEED
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٨٢٨
Used in USA
Fig. (14.14)
Dr. Munzer Ebaid Dr. Munzer Ebaid ٢٩٢٩
Problem (14.30)
)( 43HgQn
nSpeedSpecific S ∆×==
&
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٠٣٠
Problem (14.34)
Find type of pump?
smQrpmNGiven 301600 .,: ==
Loss
partMech
T
partMech
P hg
Vgz
gp
hg
Vz
gp
h +
+++=
+++
..22
22
222
21
111 α
ρα
ρ
Apply Energy Equation between (1) & (2)
1
2
)( 43HgQn
nSpeedSpecific S ∆×==
&
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣١٣١
smQrpmNGiven 301600 .,: ==
42DQV
π
&=
01.0=f
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٢٣٢
PROBLEMS ON
NPSH
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٣٣٣
Problem (14.33)
?max =N
tempVapourpptempliquidgivenpressurevapourpressureSuctionNPSH
@2
.@−=
−=
( ) 4343
21
NPSHgNQNSS =
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٤٣٤
T=60 F
5910462
1442560 ..
. =×=pressurevapourh
Axial Flow Pump
gpmQ 5000=&
Problem (14.33)
?max =N
tempVapourpptempliquidgivenpressurevapourpressureSuctionNPSH
@2
.@−=
−=
atmossuction Pftp += 5
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٥٣٥
Problem (14.38)
SHAFTactual
theoComp P
P)(
=η
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٦٣٦
Problem (14.38)
SHAFTactual
theoComp P
P)(
=η
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٧٣٧
Problem (14.38)
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٨٣٨
Problem (14.38)
Dr. Munzer Ebaid Dr. Munzer Ebaid ٣٩٣٩
PROBLEMS ON
WIND TURBINES
Dr. Munzer Ebaid Dr. Munzer Ebaid ٤٠٤٠
Problem (14.48)
U: Wind speed
A: Area captured by the wind turbine
Dr. Munzer Ebaid Dr. Munzer Ebaid ٤١٤١
Problem (14.48)
?=CaptureA
Dr. Munzer Ebaid Dr. Munzer Ebaid ٤٢٤٢
END OF SOLVED PROBLEMS
