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Inlet
Ideal Turbofan Cycle
totalm
1 2 34 5 6
7h
7c
Total thrust is generated by both cold and hot jets..
corem&
fanm&
fanm&
totalm&
corem& corem
&
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Analysis of fan
= 0,003 prp fanp = 0,003 TT fanp
Inlet
2 3
a
irm
fanm
corem
Design Parameter : Stagnation pressure ratio
( ) ( )fanppcorefan TcmW ,00 11 +=
Analysis of Fan
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Analysis of Compressor
= 0,0,004 prrp comppfanp = 0,0,004 TT comppfanp
( )comppfanppcorecompressor TcmW ,0,00 1 =
Inlet
Design Parameter : Stagnationpressure ratio
3
airm
fanm
corem
4
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Inlet
airm
fanm
corem
4 5
( )( )comppfanpccpcorefuel fTcmVHm ,0,0,00 1 +=
( )
cc
p
comppfanpcc
Tc
VHf,0
0
,0,0,0
=
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Com!ine" #as Dynami$ % &'ermo"ynami$ SSSF mo"el for &ur!ine
Inlet
airm
fanm
corem
5 (
( ) ( )turbpccpcoreturbine TcfmW ,00,0 11 +=
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( ) ( ) ( )
( ) cc
fanpcomppfanp
turbp f ,0
,0,0,0
,0 1
111
1
+
++=
=
0,0,00( TT turbpcc
1
,0,0
=
turbpturbpr
= 0,0,0,00( prrrp turbpcomppfanp
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)igor of *ot +et
= 0,0,00( TT turbpcc
= 0,0,0,00( prrrp turbpcomppfanp
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Com!ine" #as Dynami$ % &'ermo"ynami$ SSSF mo"el for *ot
o--le
( ) ( ) hcorecore hfmhfm 0.0( 11 +=+
hTT 0.0(=
0(
2
..2
11 TMT hh =
+
( ) ( ) ( )( )
+
++=
0
,0
,0,0,0
,00(1
1111 T
fT
cc
fanpcomppfanp
cc
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( ) ( ) ( )( )
+
+
++
=
2
.
0
,0
,0,0,0
,0
.
2
11
1
1111
h
cc
fanpcomppfanp
cc
h
M
Tf
T
A/aila!le life at t'e inlet to t'e no--le ill "e$i"e t'e
magnitu"e of T7h.
== 0,0,0,00(0. prrrpp turbpcomppfanph
=
+
0,0,0,0
12
.2
11
prrrMp turbpcomppfanph
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=
11
2
1
0,0,0,0.
p
prrrM turbpcomppfanph
( ) ( ) ( )( )
+
+
++
=
2
.
0,0
,0
,0,0,0
.
2
11
1
1111
h
cc
cc
fanpcomppfanp
h
M
Tf
T
( ) ( ) ( )( )
+
++
=
1
0,0,0,0
0,0
,0
,0,0,0
.
1
1111
p
prrr
Tf
T
turbpcomppfanp
cc
cc
fanpcomppfanp
h
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==
11
2 0,0,0,0....
T
TRTRTMV turbpcomppfanphhhh
=
1
1
2 0,0,0,0
,0,0
,0
.T
TRTV turbpcomppfanp
comppfanp
cc
h
comppfanp
cc
h
TT
,0,0
,0
.
=
=
T
T
TT
turbpcomppfanp
turbpcc
h
0,0,0,0
0,0,0
.
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20
211 acM
TT +=
=
1
1
2 0,0,0,0
,0,0
,0
.
T
TcV turbpcomppfanp
comppfanp
cc
h
+
= 12
111
2 2,0,0,0
,0,0
,0
et acturbpcomppfanp
comppfanp
cc
hot McV
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Com!ine" #as Dynami$ % &'ermo"ynami$ SSSF mo"el for Col"
o--le
ccorecore hmhm 0.03
= =
+ 0,0
2
..2
11 TMT fanpcc
= TTc.
1
0,0
03
1
03
03.
=
=
prpT
ppTT
fanp
c
1
0,0
0,0.
= pr pTT fanpfanpc
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==
1
1
2 0,0...
T
TRTRTMV fanpccc
=
+ 0,0
2
..2
11 TMT fanpcc
=
+
T
TM fanpc
0
,0
2
.2
11
=
11
2 0,0
2
.T
TM fanpc
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+
== 12
11
1
2 2,0.. acfanpcccoldjet McRTMV
+
= 1
2
11
1
2 2,0,0,0
,0,0
,0
acturbpcomppfanp
comppfanp
cc
hotjet McV
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#eneration of &'rust : &'e Capa$ity
{ } ( ){ }achotjetcoreaccoldjetcorecorestreamTfanstreamTtotalT
VVfmVVm
FFF
++=
+=
1,,,
Propulsi/e Poer or &'rust Poer: actotalTp VFP ,=
Spe$ifi$ &'rust !ase" on $ore flo S
core
totalT
core m
FS
,=
Spe$ifi$ &'rust !ase" on total flo S
( )+
=
1
,
core
totalT
total
m
FS
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&'rust atio
atio of spe$ifi$ t'rust of $ore stream to spe$ifi$ t'rust offan stream
fan
core
fan
fan
core
core
FF
m
Fm
F
FR ==
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&'rust Spe$ifi$ Fuel Consumption TSFC
totalT
fuel
F
mTSFC
,
=
( ){ } { }
( ){ } { }accoldjetachotjet
jetcoldcoreachotjetcore
fuel
VVVVf
f
VVmVVfm
mTSFC
++=
++=
1
1
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A/iation Appre$iation
Propulsion ffi$ien$y
+ett'eofPoerineti$A/aila!le
PowerThrustpropulsion =
( ){ } { }[ ]2222,
12
accoldjetachotjetcore
actotalTpropulsion
VVVVfm
VF
++=
( ){ } { }212221
2VVVVf
VScoldjetachotjet
accorepropulsion
++=
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Performan$e Analysis of &ur!ofan
6perational Parameters : Flig't 7a$' num!er % Am!ient
$on"itions
Design )aria!les : Fan Pressure atio, 8ypass atio,
Compressor Pressure atio, Com!ustion C'am!er
&emperature atio
Fan ffe$ts :
Fan Pressure atio
8ypass atio
Fan Stream &'rust )s &otal &'rust
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ac
total
V
S
ac
core
V
S
TSFC
9tility of of Fan 8ypass atio
r!p!fan"#.$ r!p!comp"&$
Tma'"( Mac".7$
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Fan ffe$ts : Fan Pressure atio: 7a$; 0.5
r!p!comp"&$.
=4.0Tma'"(
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ffe$t of Flig't 7a$' um!er : Compa$tness
Spe
$ifi$&'rus
t