analysis of thrust equation for ideal turbo jet engine p m v subbarao professor mechanical...
TRANSCRIPT
Analysis of Thrust Equation for Ideal Turbo Jet Engine
P M V Subbarao
Professor
Mechanical Engineering Department
Understanding the Features of A True Flying Machine Muscles
….
Ideal Turbo Jet Cycle
T0
1,2
3
4
5,6
s
p0
s
1,2
34
5,6
Ideal Turbo Jet Cycle
Thrust
acjetairT VVfmF 1
pTVStation ac &,:1
fppfV jet &, 030
pTVStation ac &,:1
002002 &, ppTTVci
0,0030,003 & prpTT comppcompp
0,0040,004 & prpTT comppcc
cc
p
comppcc
TcVH
f
00
,00
..
Thrust
Isentropic Expansion in an Active Turbine
0,0,0,00405 TTT turbpccturbp
0,0,005 prrp comppturbp
turbppturbine TcfmW ,004 11
Theory of Jet Propulsion : Jet Enough Work
The power input to the compressor = The power output of the turbine
turbinecompressor WW
turbppcomppp TcfmTcm ,004,00 111
turbpcompp TfT ,004,00 111
0,004 TT cc
0,0,0,00 111 TfT ccturbpcompp
ccturbpcompp f ,0,0,0 111
cc
comppturbp f ,0
,0,0 1
11
cc
comppturbp f ,0
,0,0 1
11
cc
comppccpturbine
fTcfmW
,0
,00,0 1
111
05041 TTcfmW pturbine
Isentropic Expansion in a Passive Turbine(Nozzle)
Thermodynamic SSSF model for Nozzle
0605 11 hfmhfm
06050605 & ppTT
2
26
605
VTcTc pp
605
26
2TTc
Vp
1
0505
1
05
6056
p
pT
p
pTT
Limit of Utilization: Open Cycle Engine: Just to Ambient Pressure!!!
04,00504,005 & prpTT turbpturbp
1
04,004,06
pr
pTT
turbpturbp
1
04
1
,004,06
1
p
p
rTT
turbpturbp
1
04046
p
pTT
0,00304 prpp compp
1
0,0046
pr
pTT
compp
1
0,0
046
1
p
p
r
TT
compp
1
0,0
046
p
pTT
compp
1
0,0
,006
p
pTT
compp
cc
605
26
2TTc
Vp
Maximum Obtainable Jet Kinetic Energy:
compp
ccTT,0
,06
04,0
,005 1
11 T
fT
cc
compp
04,005 TT turbp
00
04
,0
,005 1
11 T
T
T
fT
cc
compp
0,0,0
,005 1
11 T
fT cc
cc
compp
cc
p
comppcc
TcVH
f
00
,00
..
62 05
26 TTcV
p
compp
ccTT,0
,06
0,0,0
,005 1
11 T
fT cc
cc
compp
62 05
26 TTcV
p
compp
cccc
cc
comppp TT
fc
V
,0
,00,0
,0
,02
6
1
11
2
cc
p
comppcc
TcVH
f
00
,00
..
compp
cccc
cc
ccp
comppcc
comppp TT
TcVH
cV
,0
,00,0
,0
00
,00
,02
6
..1
11
2
compp
cccc
cc
comppp T
T
fTc
V
,0
,00,0
,0
,02
6
1
11
2
Generation of Thrust : The Capacity
acjetT VVfmF 1
ac
compp
cccc
cc
compppT V
T
T
fTcfmF
,0
,00,0
,0
,0
1
1121
compp
cccc
cc
compppjet T
T
fTcV
,0
,00,0
,0
,0
1
112
Specific Thrust S
acjet VVfS 1
ac
compp
cccc
cc
comppp V
T
T
fTcfS
,0
,00,0
,0
,0
1
1121
Propulsive Power or Thrust Power:
acjetacacTp VVfmVVFP 1
Thrust Specific Fuel Consumption TSFC
acjetacjet
fuel
T
fuel
VVf
f
VVfm
m
F
mTSFC
11
ac
compp
cccc
cc
comppp V
TT
fTcf
fTSFC
,0
,00,0
,0
,0
1
1121
Aviation Appreciation
Propulsion Efficiency
Jet theofPower Kinetic Available
PowerThrustpropulsion
2212 acjet
acTpropulsion
VVfm
VF
22)1(
2
1
acjet
acacjetpropulsion
VVfm
VVVfm
22)1(
12
acjet
acacjetpropulsion VVf
VVVf
compp
cccc
cc
compppjet T
T
fTcV
,0
,00,0
,0
,0
1
112
Thermodynamic Appreciation
Thermodynamic Efficiency
InputPower Thermal
Jet theofPower Kinetic Availablethermal
..
12
22
VHm
VVfm
fuel
acjet
thermal
..
121 22
VHf
VVf acjet
thermal
22)1(
12
acjet
acacjetpropulsion VVf
VVVf
thermalpropulsionoveral
..
121 22
VHf
VVf acjet
thermal
22)1(
12
acjet
acacjetpropulsion VVf
VVVf
thermalpropulsionoveral
..
121 22
VHf
VVf acjet
thermal
Jet engine Performance Parameters
ac
compp
cccc
cc
comppp V
TT
fTcf
fTSFC
,0
,00,0
,0
,0
1
1121
ac
compp
cccc
cc
comppp V
T
T
fTcfS
,0
,00,0
,0
,0
1
1121