Thrust-specific fuel consumption

From Wikipedia the free encyclopedia

Thrust-specific fuel consumption (TSFC) is the fuel efficiency of an engine design with respect to thrust output. TSFC may also be thought of as fuel consumption (grams/second) per unit of thrust (newtons, or N), hence thrust-specific. This figure is inversely proportional to specific impulse, which is the amount of thrust produced per unit fuel consumed.

TSFC or SFC for thrust engines (e.g. turbojets, turbofans, ramjets, rockets, etc.) is the mass of fuel needed to provide the net thrust for a given period e.g. lb/(h·lbf) (pounds of fuel per hour-pound of thrust) or g/(s·kN) (grams of fuel per second-kilonewton). Mass of fuel is used, rather than volume (gallons or litres) for the fuel measure, since it is independent of temperature.[1]

Specific fuel consumption of air-breathing jet engines at their maximum efficiency is more or less proportional to exhaust speed. The fuel consumption per mile or per kilometre is a more appropriate comparison for aircraft that travel at very different speeds.[citation needed] There also exists power-specific fuel consumption, which equals the thrust-specific fuel consumption divided by speed. It can have units of pounds per hour per horsepower.

Significance of SFC[edit]

SFC is dependent on engine design, but differences in the SFC between different engines using the same underlying technology tend to be quite small. Increasing overall pressure ratio on jet engines tends to decrease SFC.

In practical applications, other factors are usually highly significant in determining the fuel efficiency of a particular engine design in that particular application. For instance, in aircraft, turbine (jet and turboprop) engines are typically much smaller and lighter than equivalently powerful piston engine designs, both properties reducing the levels of drag on the plane and reducing the amount of power needed to move the aircraft. Therefore, turbines are more efficient for aircraft propulsion than might be indicated by a simplistic look at the table below.

SFC varies with throttle setting, altitude, climate. For jet engines, air flight speed is an important factor too. Air flight speed counteracts the jet's exhaust speed. (In an artificial and extreme case with the aircraft flying exactly at the exhaust speed, one can easily imagine why the jet's net thrust should be near zero.) Moreover, since work is force (i.e., thrust) times distance, mechanical power is force times speed. Thus, although the nominal SFC is a useful measure of fuel efficiency, it should be divided by speed when comparing engines at different speeds.

For example, Concorde cruised at 1354 mph, or 7.15 million feet per hour, with its engines giving an SFC of 1.195 lb/(lbf·h) (see below); this means the engines transferred 5.98 million foot pounds per pound of fuel (17.9 MJ/kg), equivalent to an SFC of 0.50 lb/(lbf·h) for a subsonic aircraft flying at 570 mph, which would be better than even modern engines; the Olympus 593 used in the Concorde was the world's most efficient jet engine.[2][3] However, Concorde ultimately has a heavier airframe and, due to being supersonic, is less aerodynamically efficient, i.e., the lift to drag ratio is far lower. In general, the total fuel burn of a complete aircraft is of far more importance to the customer.

Units[edit]

Specific impulse
(by weight)
Specific impulse
(by mass)
Effective
exhaust velocity
Specific fuel consumption
SI =X seconds =9.8066 X N·s/kg =9.8066 X m/s =101,972 (1/X) g/(kN·s) / {g/(kN·s)=s/m}
Imperial units =X seconds =X lbf·s/lb =32.16 X ft/s =3,600 (1/X) lb/(lbf·h)

Typical values of SFC for thrust engines[edit]

Rocket engines in vacuum
Model Type First
run
Application TSFC Isp (by weight) Isp (by weight)
lb/lbf·h g/kN·s s m/s
Merlin 1D liquid fuel 2013 Falcon 9 12 330 310 3000
Avio P80 solid fuel 2006 Vega stage 1 13 360 280 2700
Avio Zefiro 23 solid fuel 2006 Vega stage 2 12.52 354.7 287.5 2819
Avio Zefiro 9A solid fuel 2008 Vega stage 3 12.20 345.4 295.2 2895
RD-843 liquid fuel Vega upper stage 11.41 323.2 315.5 3094
Kuznetsov NK-33 liquid fuel 1970s N-1F, Soyuz-2-1v stage 1 10.9 308 331[4] 3250
NPO Energomash RD-171M liquid fuel Zenit-2M, -3SL, -3SLB, -3F stage 1 10.7 303 337 3300
LE-7A cryogenic H-IIA, H-IIB stage 1 8.22 233 438 4300
Snecma HM-7B cryogenic Ariane 2, 3, 4, 5 ECA upper stage 8.097 229.4 444.6 4360
LE-5B-2 cryogenic H-IIA, H-IIB upper stage 8.05 228 447 4380
Aerojet Rocketdyne RS-25 cryogenic 1981 Space Shuttle, SLS stage 1 7.95 225 453[5] 4440
Aerojet Rocketdyne RL-10B-2 cryogenic Delta III, Delta IV, SLS upper stage 7.734 219.1 465.5 4565
NERVA NRX A6 nuclear 1967 869
Jet engines with Reheat, static, sea level
Model Type First
run
Application TSFC Isp (by weight) Isp (by weight)
lb/lbf·h g/kN·s s m/s
Turbo-Union RB.199 turbofan Tornado 2.5[6] 70.8 1440 14120
GE F101-GE-102 turbofan 1970s B-1B 2.46 70 1460 14400
Tumansky R-25-300 turbojet MIG-21bis 2.206[6] 62.5 1632 16000
GE J85-GE-21 turbojet F-5E/F 2.13[6] 60.3 1690 16570
GE F110-GE-132 turbofan F-16E/F 2.09[6] 59.2 1722 16890
Honeywell/ITEC F125 turbofan F-CK-1 2.06[6] 58.4 1748 17140
Snecma M53-P2 turbofan Mirage 2000C/D/N 2.05[6] 58.1 1756 17220
Snecma Atar 09C turbojet Mirage III 2.03[6] 57.5 1770 17400
Snecma Atar 09K-50 turbojet Mirage IV, 50, F1 1.991[6] 56.4 1808 17730
GE J79-GE-15 turbojet F-4E/EJ/F/G, RF-4E 1.965 55.7 1832 17970
Saturn AL-31F turbofan Su-27/P/K 1.96[7] 55.5 1837 18010
GE F110-GE-129 turbofan F-16C/D, F-15EX 1.9[6] 53.8 1895 18580
Soloviev D-30F6 turbofan MiG-31, S-37/Su-47 1.863[6] 52.8 1932 18950
Lyulka AL-21F-3 turbojet Su-17, Su-22 1.86[6] 52.7 1935 18980
Klimov RD-33 turbofan 1974 MiG-29 1.85 52.4 1946 19080
Saturn AL-41F-1S turbofan Su-35S/T-10BM 1.819 51.5 1979 19410
Volvo RM12 turbofan 1978 Gripen A/B/C/D 1.78[6] 50.4 2022 19830
GE F404-GE-402 turbofan F/A-18C/D 1.74[6] 49 2070 20300
Kuznetsov NK-32 turbofan 1980 Tu-144LL, Tu-160 1.7 48 2100 21000
Snecma M88-2 turbofan 1989 Rafale 1.663 47.11 2165 21230
Eurojet EJ200 turbofan 1991 Eurofighter 1.66–1.73 47–49[8] 2080–2170 20400–21300
Dry jet engines, static, sea level
Model Type First
run
Application TSFC Isp (by weight) Isp (by weight)
lb/lbf·h g/kN·s s m/s
GE J85-GE-21 turbojet F-5E/F 1.24[6] 35.1 2900 28500
Snecma Atar 09C turbojet Mirage III 1.01[6] 28.6 3560 35000
Snecma Atar 09K-50 turbojet Mirage IV, 50, F1 0.981[6] 27.8 3670 36000
Snecma Atar 08K-50 turbojet Super Étendard 0.971[6] 27.5 3710 36400
Tumansky R-25-300 turbojet MIG-21bis 0.961[6] 27.2 3750 36700
Lyulka AL-21F-3 turbojet Su-17, Su-22 0.86 24.4 4190 41100
GE J79-GE-15 turbojet F-4E/EJ/F/G, RF-4E 0.85 24.1 4240 41500
Snecma M53-P2 turbofan Mirage 2000C/D/N 0.85[6] 24.1 4240 41500
Volvo RM12 turbofan 1978 Gripen A/B/C/D 0.824[6] 23.3 4370 42800
RR Turbomeca Adour turbofan 1999 Jaguar retrofit 0.81 23 4400 44000
Honeywell/ITEC F124 turbofan 1979 L-159, X-45 0.81[6] 22.9 4440 43600
Honeywell/ITEC F125 turbofan F-CK-1 0.8[6] 22.7 4500 44100
PW J52-P-408 turbojet A-4M/N, TA-4KU, EA-6B 0.79 22.4 4560 44700
Saturn AL-41F-1S turbofan Su-35S/T-10BM 0.79 22.4 4560 44700
Snecma M88-2 turbofan 1989 Rafale 0.782 22.14 4600 45100
Klimov RD-33 turbofan 1974 MiG-29 0.77 21.8 4680 45800
RR Pegasus 11-61 turbofan AV-8B+ 0.76 21.5 4740 46500
Eurojet EJ200 turbofan 1991 Eurofighter 0.74–0.81 21–23[8] 4400–4900 44000–48000
GE F414-GE-400 turbofan 1993 F/A-18E/F 0.724[9] 20.5 4970 48800
Kuznetsov NK-32 turbofan 1980 Tu-144LL, Tu-160 0.72-0.73 20–21 4900–5000 48000–49000
Soloviev D-30F6 turbofan MiG-31, S-37/Su-47 0.716[6] 20.3 5030 49300
Snecma Larzac turbofan 1972 Alpha Jet 0.716 20.3 5030 49300
IHI F3 turbofan 1981 Kawasaki T-4 0.7 19.8 5140 50400
Saturn AL-31F turbofan Su-27 /P/K 0.666-0.78[7][9] 18.9–22.1 4620–5410 45300–53000
RR Spey RB.168 turbofan AMX 0.66[6] 18.7 5450 53500
GE F110-GE-129 turbofan F-16C/D, F-15 0.64[9] 18 5600 55000
GE F110-GE-132 turbofan F-16E/F 0.64[9] 18 5600 55000
Turbo-Union RB.199 turbofan Tornado ECR 0.637[6] 18.0 5650 55400
PW F119-PW-100 turbofan 1992 F-22 0.61[9] 17.3 5900 57900
Turbo-Union RB.199 turbofan Tornado 0.598[6] 16.9 6020 59000
GE F101-GE-102 turbofan 1970s B-1B 0.562 15.9 6410 62800
PW TF33-P-3 turbofan B-52H, NB-52H 0.52[6] 14.7 6920 67900
RR AE 3007H turbofan RQ-4, MQ-4C 0.39[6] 11.0 9200 91000
GE F118-GE-100 turbofan 1980s B-2 0.375[6] 10.6 9600 94000
GE F118-GE-101 turbofan 1980s U-2S 0.375[6] 10.6 9600 94000
General Electric CF6-50C2 turbofan A300, DC-10-30 0.371[6] 10.5 9700 95000
GE TF34-GE-100 turbofan A-10 0.37[6] 10.5 9700 95000
CFM CFM56-2B1 turbofan C-135, RC-135 0.36[10] 10 10000 98000
Progress D-18T turbofan 1980 An-124, An-225 0.345 9.8 10400 102000
PW F117-PW-100 turbofan C-17 0.34[11] 9.6 10600 104000
PW PW2040 turbofan Boeing 757 0.33[11] 9.3 10900 107000
CFM CFM56-3C1 turbofan 737 Classic 0.33 9.3 11000 110000
GE CF6-80C2 turbofan 744, 767, MD-11, A300/310, C-5M 0.307-0.344 8.7–9.7 10500–11700 103000–115000
EA GP7270 turbofan A380-861 0.299[9] 8.5 12000 118000
GE GE90-85B turbofan 777-200/200ER/300 0.298[9] 8.44 12080 118500
GE GE90-94B turbofan 777-200/200ER/300 0.2974[9] 8.42 12100 118700
RR Trent 970-84 turbofan 2003 A380-841 0.295[9] 8.36 12200 119700
GE GEnx-1B70 turbofan 787-8 0.2845[9] 8.06 12650 124100
RR Trent 1000C turbofan 2006 787-9 0.273[9] 7.7 13200 129000
Jet engines, cruise
Model Type First
run
Application TSFC Isp (by weight) Isp (by weight)
lb/lbf·h g/kN·s s m/s
Ramjet Mach 1 4.5 130 800 7800
J-58 turbojet 1958 SR-71 at Mach 3.2 (Reheat) 1.9[6] 53.8 1895 18580
RR/Snecma Olympus turbojet 1966 Concorde at Mach 2 1.195[12] 33.8 3010 29500
PW JT8D-9 turbofan 737 Original 0.8[13] 22.7 4500 44100
Honeywell ALF502R-5 GTF BAe 146 0.72[11] 20.4 5000 49000
Soloviev D-30KP-2 turbofan Il-76, Il-78 0.715 20.3 5030 49400
Soloviev D-30KU-154 turbofan Tu-154M 0.705 20.0 5110 50100
RR Tay RB.183 turbofan 1984 Fokker 70, Fokker 100 0.69 19.5 5220 51200
GE CF34-3 turbofan 1982 Challenger, CRJ100/200 0.69 19.5 5220 51200
GE CF34-8E turbofan E170/175 0.68 19.3 5290 51900
Honeywell TFE731-60 GTF Falcon 900 0.679[14] 19.2 5300 52000
CFM CFM56-2C1 turbofan DC-8 Super 70 0.671[11] 19.0 5370 52600
GE CF34-8C turbofan CRJ700/900/1000 0.67-0.68 19–19 5300–5400 52000–53000
CFM CFM56-3C1 turbofan 737 Classic 0.667 18.9 5400 52900
CFM CFM56-2A2 turbofan 1974 E-3, E-6 0.66[10] 18.7 5450 53500
RR BR725 turbofan 2008 G650/ER 0.657 18.6 5480 53700
CFM CFM56-2B1 turbofan C-135, RC-135 0.65[10] 18.4 5540 54300
GE CF34-10A turbofan ARJ21 0.65 18.4 5540 54300
CFE CFE738-1-1B turbofan 1990 Falcon 2000 0.645[11] 18.3 5580 54700
RR BR710 turbofan 1995 G. V/G550, Global Express 0.64 18 5600 55000
GE CF34-10E turbofan E190/195 0.64 18 5600 55000
General Electric CF6-50C2 turbofan A300B2/B4/C4/F4, DC-10-30 0.63[11] 17.8 5710 56000
PowerJet SaM146 turbofan Superjet LR 0.629 17.8 5720 56100
CFM CFM56-7B24 turbofan 737 NG 0.627[11] 17.8 5740 56300
RR BR715 turbofan 1997 717 0.62 17.6 5810 56900
GE CF6-80C2-B1F turbofan 747-400 0.605[12] 17.1 5950 58400
CFM CFM56-5A1 turbofan A320 0.596 16.9 6040 59200
Aviadvigatel PS-90A1 turbofan Il-96-400 0.595 16.9 6050 59300
PW PW2040 turbofan 757-200 0.582[11] 16.5 6190 60700
PW PW4098 turbofan 777-300 0.581[11] 16.5 6200 60800
GE CF6-80C2-B2 turbofan 767 0.576[11] 16.3 6250 61300
IAE V2525-D5 turbofan MD-90 0.574[15] 16.3 6270 61500
IAE V2533-A5 turbofan A321-231 0.574[15] 16.3 6270 61500
RR Trent 700 turbofan 1992 A330 0.562[16] 15.9 6410 62800
RR Trent 800 turbofan 1993 777-200/200ER/300 0.560[16] 15.9 6430 63000
Progress D-18T turbofan 1980 An-124, An-225 0.546 15.5 6590 64700
CFM CFM56-5B4 turbofan A320-214 0.545 15.4 6610 64800
CFM CFM56-5C2 turbofan A340-211 0.545 15.4 6610 64800
RR Trent 500 turbofan 1999 A340-500/600 0.542[16] 15.4 6640 65100
CFM LEAP-1B turbofan 2014 737 MAX 0.53-0.56 15–16 6400–6800 63000–67000
Aviadvigatel PD-14 turbofan 2014 MC-21-310 0.526 14.9 6840 67100
RR Trent 900 turbofan 2003 A380 0.522[16] 14.8 6900 67600
GE GE90-85B turbofan 777-200/200ER 0.52[11][17] 14.7 6920 67900
GE GEnx-1B76 turbofan 2006 787-10 0.512[13] 14.5 7030 69000
PW PW1400G GTF MC-21 0.51[18] 14.4 7100 69000
CFM LEAP-1C turbofan 2013 C919 0.51 14.4 7100 69000
CFM LEAP-1A turbofan 2013 A320neo family 0.51[18] 14.4 7100 69000
RR Trent 7000 turbofan 2015 A330neo 0.506[a] 14.3 7110 69800
RR Trent 1000 turbofan 2006 787 0.506[b] 14.3 7110 69800
RR Trent XWB-97 turbofan 2014 A350-1000 0.478[c] 13.5 7530 73900
PW 1127G GTF 2012 A320neo 0.463[13] 13.1 7780 76300
Civil engines[19]
Model SL thrust BPR OPR SL SFC cruise SFC Weight Layout cost ($M) Introduction
GE GE90 90,000 lbf
400 kN
8.4 39.3 0.545 lb/(lbf⋅h)
15.4 g/(kN⋅s)
16,644 lb
7,550 kg
1+3LP 10HP
2HP 6LP
11 1995
RR Trent 71,100–91,300 lbf
316–406 kN
4.89-5.74 36.84-42.7 0.557–0.565 lb/(lbf⋅h)
15.8–16.0 g/(kN⋅s)
10,550–13,133 lb
4,785–5,957 kg
1LP 8IP 6HP
1HP 1IP 4/5LP
11-11.7 1995
PW4000 52,000–84,000 lbf
230–370 kN
4.85-6.41 27.5-34.2 0.348–0.359 lb/(lbf⋅h)
9.9–10.2 g/(kN⋅s)
9,400–14,350 lb
4,260–6,510 kg
1+4-6LP 11HP
2HP 4-7LP
6.15-9.44 1986-1994
RB211 43,100–60,600 lbf
192–270 kN
4.30 25.8-33 0.570–0.598 lb/(lbf⋅h)
16.1–16.9 g/(kN⋅s)
7,264–9,670 lb
3,295–4,386 kg
1LP 6/7IP 6HP
1HP 1IP 3LP
5.3-6.8 1984-1989
GE CF6 52,500–67,500 lbf
234–300 kN
4.66-5.31 27.1-32.4 0.32–0.35 lb/(lbf⋅h)
9.1–9.9 g/(kN⋅s)
0.562–0.623 lb/(lbf⋅h)
15.9–17.6 g/(kN⋅s)
8,496–10,726 lb
3,854–4,865 kg
1+3/4LP 14HP
2HP 4/5LP
5.9-7 1981-1987
D-18 51,660 lbf
229.8 kN
5.60 25.0 0.570 lb/(lbf⋅h)
16.1 g/(kN⋅s)
9,039 lb
4,100 kg
1LP 7IP 7HP
1HP 1IP 4LP
1982
PW2000 38,250 lbf
170.1 kN
6 31.8 0.33 lb/(lbf⋅h)
9.3 g/(kN⋅s)
0.582 lb/(lbf⋅h)
16.5 g/(kN⋅s)
7,160 lb
3,250 kg
1+4LP 11HP
2HP 5LP
4 1983
PS-90 35,275 lbf
156.91 kN
4.60 35.5 0.595 lb/(lbf⋅h)
16.9 g/(kN⋅s)
6,503 lb
2,950 kg
1+2LP 13HP
2 HP 4LP
1992
IAE V2500 22,000–33,000 lbf
98–147 kN
4.60-5.40 24.9-33.40 0.34–0.37 lb/(lbf⋅h)
9.6–10.5 g/(kN⋅s)
0.574–0.581 lb/(lbf⋅h)
16.3–16.5 g/(kN⋅s)
5,210–5,252 lb
2,363–2,382 kg
1+4LP 10HP
2HP 5LP
1989-1994
CFM56 20,600–31,200 lbf
92–139 kN
4.80-6.40 25.70-31.50 0.32–0.36 lb/(lbf⋅h)
9.1–10.2 g/(kN⋅s)
0.545–0.667 lb/(lbf⋅h)
15.4–18.9 g/(kN⋅s)
4,301–5,700 lb
1,951–2,585 kg
1+3/4LP 9HP
1HP 4/5LP
3.20-4.55 1986-1997
D-30 23,850 lbf
106.1 kN
2.42 0.700 lb/(lbf⋅h)
19.8 g/(kN⋅s)
5,110 lb
2,320 kg
1+3LP 11HP
2HP 4LP
1982
JT8D 21,700 lbf
97 kN
1.77 19.2 0.519 lb/(lbf⋅h)
14.7 g/(kN⋅s)
0.737 lb/(lbf⋅h)
20.9 g/(kN⋅s)
4,515 lb
2,048 kg
1+6LP 7HP
1HP 3LP
2.99 1986
BR700 14,845–19,883 lbf
66.03–88.44 kN
4.00-4.70 25.7-32.1 0.370–0.390 lb/(lbf⋅h)
10.5–11.0 g/(kN⋅s)
0.620–0.640 lb/(lbf⋅h)
17.6–18.1 g/(kN⋅s)
3,520–4,545 lb
1,597–2,062 kg
1+1/2LP 10HP
2HP 2/3LP
1996
D-436 16,865 lbf
75.02 kN
4.95 25.2 0.610 lb/(lbf⋅h)
17.3 g/(kN⋅s)
3,197 lb
1,450 kg
1+1L 6I 7HP
1HP 1IP 3LP
1996
RR Tay 13,850–15,400 lbf
61.6–68.5 kN
3.04-3.07 15.8-16.6 0.43–0.45 lb/(lbf⋅h)
12–13 g/(kN⋅s)
0.690 lb/(lbf⋅h)
19.5 g/(kN⋅s)
2,951–3,380 lb
1,339–1,533 kg
1+3LP 12HP
2HP 3LP
2.6 1988-1992
RR Spey 9,900–11,400 lbf
44–51 kN
0.64-0.71 15.5-18.4 0.56 lb/(lbf⋅h)
16 g/(kN⋅s)
0.800 lb/(lbf⋅h)
22.7 g/(kN⋅s)
2,287–2,483 lb
1,037–1,126 kg
4/5LP 12HP
2HP 2LP
1968-1969
GE CF34 9,220 lbf
41.0 kN
21 0.35 lb/(lbf⋅h)
9.9 g/(kN⋅s)
1,670 lb
760 kg
1F 14HP
2HP 4LP
1996
AE3007 7,150 lbf
31.8 kN
24.0 0.390 lb/(lbf⋅h)
11.0 g/(kN⋅s)
1,581 lb
717 kg
ALF502/LF507 6,970–7,000 lbf
31.0–31.1 kN
5.60-5.70 12.2-13.8 0.406–0.408 lb/(lbf⋅h)
11.5–11.6 g/(kN⋅s)
0.414–0.720 lb/(lbf⋅h)
11.7–20.4 g/(kN⋅s)
1,336–1,385 lb
606–628 kg
1+2L 7+1HP
2HP 2LP
1.66 1982-1991
CFE738 5,918 lbf
26.32 kN
5.30 23.0 0.369 lb/(lbf⋅h)
10.5 g/(kN⋅s)
0.645 lb/(lbf⋅h)
18.3 g/(kN⋅s)
1,325 lb
601 kg
1+5LP+1CF
2HP 3LP
1992
PW300 5,266 lbf
23.42 kN
4.50 23.0 0.391 lb/(lbf⋅h)
11.1 g/(kN⋅s)
0.675 lb/(lbf⋅h)
19.1 g/(kN⋅s)
993 lb
450 kg
1+4LP+1HP
2HP 3LP
1990
JT15D 3,045 lbf
13.54 kN
3.30 13.1 0.560 lb/(lbf⋅h)
15.9 g/(kN⋅s)
0.541 lb/(lbf⋅h)
15.3 g/(kN⋅s)
632 lb
287 kg
1+1LP+1CF
1HP 2LP
1983
WI FJ44-4A 1,900 lbf
8.5 kN
3.28 12.80 0.456 lb/(lbf⋅h)
12.9 g/(kN⋅s)
0.75 lb/(lbf⋅h)
21 g/(kN⋅s)
445 lb
202 kg
1+1L 1C 1H
1HP 2LP
1992
WI FJ33-5A 1,000–1,800 lbf
4.4–8.0 kN
0.486 lb/(lbf⋅h)
13.8 g/(kN⋅s)
300 lb
140 kg
2016

The following table gives the efficiency for several engines when running at 80% throttle, which is approximately what is used in cruising, giving a minimum SFC. The efficiency is the amount of power propelling the plane divided by the rate of energy consumption. Since the power equals thrust times speed, the efficiency is given by

where V is speed and h is the energy content per unit mass of fuel (the higher heating value is used here, and at higher speeds the kinetic energy of the fuel or propellant becomes substantial and must be included).

typical subsonic cruise, 80% throttle, min SFC[20]
Turbofan efficiency
GE90 36.1%
PW4000 34.8%
PW2037 35.1% (M.87 40K)
PW2037 33.5% (M.80 35K)
CFM56-2 30.5%
TFE731-2 23.4%

See also[edit]

  • Brake specific fuel consumption – Measure of the fuel efficiency of internal combustion engines
  • Energies per unit mass – Energy per volume
  • Specific impulse – Change in velocity per amount of fuel
  • Vehicle metrics – Metrics that denote the relative capabilities of various vehicles

Notes[edit]

  1. ^ 10% better than Trent 700
  2. ^ 10% better than Trent 700
  3. ^ 15 per cent fuel consumption advantage over the original Trent engine

References[edit]

  1. ^ Specific Fuel Consumption.
  2. ^ Supersonic Dream
  3. ^ "The turbofan engine Archived 2015-04-18 at the Wayback Machine", page 5. SRM Institute of Science and Technology, Department of aerospace engineering
  4. ^ "NK33". Encyclopedia Astronautica.
  5. ^ "SSME". Encyclopedia Astronautica.
  6. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag Nathan Meier (21 Mar 2005). "Military Turbojet/Turbofan Specifications". Archived from the original on 11 February 2021.
  7. ^ a b "Flanker". AIR International Magazine. 23 March 2017.
  8. ^ a b "EJ200 turbofan engine" (PDF). MTU Aero Engines. April 2016.
  9. ^ a b c d e f g h i j k Kottas, Angelos T.; Bozoudis, Michail N.; Madas, Michael A. "Turbofan Aero-Engine Efficiency Evaluation: An Integrated Approach Using VSBM Two-Stage Network DEA" (PDF). doi:10.1016/j.omega.2019.102167.
  10. ^ a b c Élodie Roux (2007). "Turbofan and Turbojet Engines: Database Handbook" (PDF). p. 126. ISBN 9782952938013.
  11. ^ a b c d e f g h i j k Nathan Meier (3 Apr 2005). "Civil Turbojet/Turbofan Specifications". Archived from the original on 17 August 2021.
  12. ^ a b Ilan Kroo. "Data on Large Turbofan Engines". Aircraft Design: Synthesis and Analysis. Stanford University. Archived from the original on 11 January 2017.
  13. ^ a b c David Kalwar (2015). "Integration of turbofan engines into the preliminary design of a high-capacity short-and medium-haul passenger aircraft and fuel efficiency analysis with a further developed parametric aircraft design software" (PDF).
  14. ^ "Purdue School of Aeronautics and Astronautics Propulsion Web Page - TFE731".
  15. ^ a b Lloyd R. Jenkinson & al. (30 Jul 1999). "Civil Jet Aircraft Design: Engine Data File". Elsevier/Butterworth-Heinemann.
  16. ^ a b c d "Gas Turbine Engines" (PDF). Aviation Week. 28 January 2008. pp. 137–138.
  17. ^ Élodie Roux (2007). "Turbofan and Turbojet Engines: Database Handbook". ISBN 9782952938013.
  18. ^ a b Vladimir Karnozov (August 19, 2019). "Aviadvigatel Mulls Higher-thrust PD-14s To Replace PS-90A". AIN Online.
  19. ^ Lloyd R. Jenkinson; et al. (30 Jul 1999). "Civil Jet Aircraft Design: Engine Data File". Elsevier/Butterworth-Heinemann.
  20. ^ Ilan Kroo. "Specific Fuel Consumption and Overall Efficiency". Aircraft Design: Synthesis and Analysis. Stanford University. Archived from the original on November 24, 2016.

External links[edit]