Seit

e 1

Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

SC.

Otto engine

90 barn/a

pmax: 200 barLarge e.

Diesel engine

180 barPC

200 barTruck

70

65

60

55

50

45

40

35

304 6 8 10 12 14 16 18 20 22

Compression ratio ε [–]

Eff

icie

ncy

otth

eid

eal engin

eη

ide

al[%

]

21,61,41,2

64

0,9

0,8

1

Consta

ntvolu

me,

aspirate

dengin

e

Thermodynamic Potential and Limits of IC Engines

Univ.-Prof. Dr. Helmut Eichlseder

A3 PS ConferenceVienna, 18th 19th November 2010

Seit

e 2Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

g Introduction

g Boundary conditions

g Challenges today and tomorrow

• Efficiency

• Emission

• Specific Power

g Additional Chances for the future

g Summary

Thermodynamic Potential and Limits Challenges and risks for IC engines

Seit

e 3Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Driving more than 99 % of passenger cars

IC engine is one of the most successful

inventions

Production >70 mio.per year

But:

The biggest challenge for ICE

is its success

Today: More than 1000 million IC engines

Seit

e 4Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

SC.

Gasoline engine

90 barn/a

pmax 200 barLarge e.

Diesel engine

180 barPC

200 barTruck

70

65

60

55

50

45

40

35

30

4 6 8 10 12 14 16 18 20 22

Compression ratio ε [–]

Eff

icie

ncy o

f th

e ideal engin

e η

ide

al[%

]

21,61,41,2

64

0,9

0,8

1

Consta

nt volu

me,

aspirate

d e

ngin

e

Efficiency of the ideal

engine

Thermodynamic boundary conditions

� Constant volume-constant pressure combustion

� Peak pressure limitation

Limit: Efficiency of the ideal engine

λλλλ

Seit

e 5Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

0

5

10

15

20

25

30

35

40

45

en

gin

e e

ffic

ien

cy [

%]

Efficiency of real enginesEngine Categories - Comparison

MOPED

50 cm³

MOTORCYCLE

800 cm³

PASSENGER CAR

SI

PASSENGER CAR

DIESEL

TRUCK STATIONARY

LARGE ENGINE

best value representative operation (test cycle)

Seit

e 6Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Efficiency increase by shift of operation point Example Diesel vs. Gasoline: 2.0 dm3 engine in equal vehicle

0

2

4

6

8

10

12

14

16

18

20

22

24

500 1000 1500 2000 2500 3000 3500 4000 4500 5000

Engine speed / min–1

BM

EP

/ b

ar

Operating points NEDC Gasoline

Operating points NEDC Diesel

Full load curve Gasoline

Full load curve Diesel

Mean value Gasoline

Mean value Diesel

Seit

e 7Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Example: MPI Gasoline engine (λλλλ = 1)

BMEP / bar

Eff

icie

nc

y ηη ηη

, lo

sses ∆

η∆

η∆

η∆

η/

%

∆η∆η∆η∆ηrc ∆η∆η∆η∆ηWH ∆η∆η∆η∆ηGE

0 2 4 6 8 10

∆η∆η∆η∆ηm

ηηηηirc

ηηηηi

ηηηηe

50

40

30

20

10

0

∆η∆η∆η∆ηic Lean Operation

Efficiency increase by de-throttling and load shift

Fully variable

valve train

Cylinder deactivation

Downsizing (Gasoline DI TC,

Diesel 2stage TC)

Electrification/

Hybrid

Seit

e 8Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

0

5

10

15

20

25

30

35

40E

ffe

cti

ve

Eff

icie

nc

y[%

]Average Otto DI

Average Diesel DI

VW Lupo 1.2 TDI

0

25

50

75

100

125

0 200 400 600 800 1000 1200

Time [s]

Velo

cit

y[k

m/h

]

NEDCArtemis

Urban

Artemis

Road

Effective efficiency of passenger car drivetrains

NEDC ArtemisRoad

ArtemisUrban

EUDCECE 15 4 NEDC

GM Diesel vehicle

GM Fuel Cel vehicle

Source:

von Helmolt, Eberle (GM)

in „Hydrogen Technology“

ISBN: 978-3-540-79027-3

Chassis dynamometer

measurements at TU Graz

Seit

e 9Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

g Electrification / Hybridization

• Start/Stop

• Shift of operating point

• Energy recovery

• Electric drive in low load/speed

g Thermal management for improved warm up

g Waste heat recovery

Further potential for efficiency improvement

Seit

e 1

0Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Increase of system efficiencyWaste heat recovery – Concepts

Lit.: SAE 930880, 1993 (Toyota)

Lit.: SAE 790646, 1979

Thermoelectric generator / source: BMW

Seit

e 1

1Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Increase of system efficiency Waste heat recovery – Potential for trucks

Source: Gstrein, FPT (Iveco)

84

88

92

96

100

104

Bas

e tr

uck

T-Com

pound

E-Com

pound

Ran

kine

Stirlin

g

Cool.w

ater

Peltie

r

Co

ns

um

pti

on

[%

]

Seit

e 1

2Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

g Introduction

g Boundary conditions

g Challenges today and tomorrow

• Efficiency

• Emission

• Specific Power

g Chances for the future

g Summary

Thermodynamic Potential and Limits Challenges and risks for IC engines

Seit

e 1

3Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Diesel passenger car

1985 1990 1995 2000 2005 2010 2015

0 %

50 %

100 %

16.5 g/kmECE R15/04

CO

7.4

2.721.0 0.64 0.5 0.5 0.5 0.62

2004

CO

0 %

50 %

100 %

5.1 g/kmECE R15/04

HC + NOx

1.97

0.97 0.7 0.56 0.3 0.23 0.17 0.012

NOx

0.08

NOx

0 %

50 %

100 %

0.27 g/km88/436/EEC

PM

EU1 EU2 EU3 EU4 EU5 EU6

0.14

0.080.05

0.0250.005 0.0045 0.0062

SULEV

PM

EU6

Emission – standards

98%

97%

97%

Example: Passenger car diesel engines

Seit

e 1

4Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

0

1

2

3

4

5

6

7

8

9

10

HC

-Ko

nz

en

tra

tio

n [

mg

/m3

]

SULEVSULEV

9.99.9

Incl. Incl. coldcold startstart

Immission

Tunnel

Urban Area

After warm upAfter warm up

Rural Area

0.5

Emission LegislationSULEV HC Emission and Immission

HC

–co

ncen

trati

on

[m

g/m

³]

Seit

e 1

5Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

g Introduction

g Boundary conditions

g Challenges today and tomorrow

• Efficiency

• Emission

• Specific Power

g Chances for the future

g Summary

Challenges and risks for IC engines

Thermodynamic Potential and Limits

Seit

e 1

6Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

BMEP of NA and Supercharged Engines

Passenger car engines

BM

EP

/ b

ar

0

5

10

15

20

25

30

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

Pe /kW/l

Engine speed / min–1

1000 2000 3000 4000 5000 6000 7000 8000

Mercedes 250CDI (MY09)BMW 740d (MY10)

Porsche 911 GT3 (MY08)Toyota Aygo 1.0 (MY06)

Porsche 911 GT2 RS (MY10)VW Golf 1.4 TSI (MY06)

Seit

e 1

7Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Specific power – potential Gasoline

Turbo-charging

� Wide application

� Synergy with DI

� Downsizing possible

� Cost efficient

Specific power >700 kW/l Durability 3 laps (qualifying)

Source: Audi

Speed

Source: BMW

Specific power 140 kW/l in series(motorcycle)

� Exclusive applications

� Excellent transient behaviour

� Sport- and racing vehicles

� High effort

Seit

e 1

8Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Source: MTU

Source: MTU

- High speed concept not possible due to combustion speed

- Increase of supercharging possible

also as two stage TC

no thermodynamic limit obvious, mechanic and

thermal limit

- Example for complex and effective

turbocharging: power boats and

military applications

- Spec. power 100 kW/l

in series production

Specific power – potential Diesel

Seit

e 1

9Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

g Introduction

g Boundary conditions

g Challenges today and tomorrow

• Efficiency

• Emission

• Specific Power

g Additional Chances for the future

g Summary

Thermodynamic Potential and Limits Challenges and risks for IC engines

Seit

e 2

0Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Alternative fuels Assessment

� Increasing share and variety, but no single „patent“ solution

Use

of e

xist

ing

Infr

astr

ucture

Applic

atio

n on

engin

eEnvi

ronm

ent

(Gre

enhouse

)Envi

ronm

ent

(Loca

l)

Rem

arks

Bio Diesel ++ +(PM-Filter)

+(-50%)

020% blending expected

until 2020

Ethanol ++ + + 0Blending,

Sugar Cane+

Natural Gas - +(knock resist.)

+(-25%)

+ (D)

0 (G)Fossil Fuel; Operation Range

BTL

(Biomass to Liquid)- ++ 0/+ (+) Energy demand for production

Biogas -- + ++ 0 similar to natural gas

Vegetable Oil - - + - Limited Availability

Hydrogen -- + ++(renewable)

++ Energy Carrier !; ICE + FC

Electric Energy - ++(renewable)

++ Based on renewable energy

Auto Gas (Propane) o o/-+

(-10%)

+ (D)

0 (G)Fossil Fuel

Seit

e 2

1Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Concept Vehicle TU Graz/HyCentAMulti Fuel

Multivalent with

Methane, Biogas and Hydrogenin one Fuel System and

Gasoline

Seit

e 2

2Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Summary

g Essential efficiency improvement by advanced combustion concepts in combination with load shift technologies (downsizing) possible

g Technology variety of SI engines continued (TC, MPI/DI, cyl. deactivation, VVT, DI stratified), key technologies will be turbocharging+DI

g Electrification of ICE (mainly Mild Hybrid) increasing

g Remarkable potential of Energy management (warm up, use of wasteenergy) and friction reduction

g Important challenge is reduction of CO2 fleet-emission, EU target of 95 g/km (2020) seems feasible (and most effective) with „reasonable“(cost-efficient) ICE

g IC engine with „zero impact“ toxic emissions possible (λλλλ=1 gasoline)

g ICE gives excellent base for Alternative Fuels

g ICE for > 20 years dominating propulsion system

Conclusions

Seit

e 2

3

Institute for Internal Combustion Engines and Thermodynamics

G r a z · U n i v e r s i t y · o f · T e c h n o l o g y

Laderm.

OttomotorenOttomotoren

90 barSaugm.

ppmaxmax:: 200 barGroßm.

DieselmotorenDieselmotoren

180 barPKW

200 barLKW

7070

6565

6060

5555

5050

4545

4040

3535

303044 66 88 1010 1212 1414 1616 1818 2020 2222

VerdichtungsverhVerdichtungsverhäältnisltnis εεεεεεεε [[--]]

Wir

ku

ng

sg

rad

des v

ollko

mm

en

en

Mo

tors

W

irku

ng

sg

rad

des v

ollko

mm

en

en

Mo

tors

hhvv

[%]

[%]

221,61,61,41,41,21,2

6644

0,0,

99

0,80,8

11

Gle

ich

rau

mG

leic

hra

um

, , S

au

gm

oto

rS

au

gm

oto

r

Thank you foryour attention

contact: eichlseder@ivt.tugraz.at