This is a part of Lecture Series on Automotive Fuels & Emissions for M. Tech Students at ARAI ACADEMY.

1. EMISSIONS
CONTROL IN
S.I. ENGINES
Dr. K. C . Vor a

2. MEASURES TO CONTROL EMISSIONS
Non technical control measures:
• Good town planning (low sky scappers/satellite cities)
• Congestion charges, area licensing scheme,
parking charges, phasing out of vehicles, etc.
• Proper traffic pattern & road networking (eg. Flyovers)
• Public awareness (energy efficient purchase,
driving habits, car pooling)
• Efficient public transport/transit system (Bus Rapid Transit)
• Promote cycling/walking/Bicycle Lanes/2 Wheeler Bridges
• Proper maintenance (I&M program: Burari))
• Prevent Adulteration of fuels
• Living with plants.

3. MEASURES TO CONTROL EMISSIONS
Technical control measures:
Clean Fuels / Alternate Fuels
Optimal design of engines
Optimization of drive line to improve fuel efficiency `
Retrofitment of new technologies
After treatment.

6. EMISSION CONTROL DEVELOPMENT
ON GASOLINE ENGINE FOR THE PAST DECADE

7. EMISSION CONTROL DEVELOPMENT
ON GASOLINE ENGINE FOR THE NEXT DECADE

8. 3 vs 4 CYL ENGINE CONFIGURATION
Bore x Stroke = 77 mm x 84 mm Bore x Stroke = 84 mm x 90 mm
0.375 x 4 = 1.5 ltr 0.5 x 3 = 1.5 ltr
96
88
4 cyl φ 84 3 cyl
φ 77
115
108
375 mm 310 mm
Particulars 3 cyl engine characteristics over 4 cyl
( for equivalent total displacement )
Length Lower (better for packaging)
No of components Lower
Weight Lower
Cost Lower (because of reduced no. of components)
Friction Lower (because of reduced no. of components)
Volumetric efficiency Better (because of larger bore)
Combustion Better (because of larger bore)
NVH & Stiffer crankcase but poor balancing.
Balancing primary & secondary couples will be balanced
8 Based on above, a 3 cylinder configuration is suggested

9. 9

10. BENCH MARKING (Power & Torque)
CAR MUV
55
19 0
17 0 CAR-MNC (DI/CRDI/UI)
15 0
13 0
CAR - INDIAN (DI)
110
CAR-INDIAN (IDI)
45 90
70 UTILITY-MNC
50
0. 3 0.35 0.4 UTILITY-INDIAN
0. 45 0. 5 0.55 0.6 0.65 0.7 0.75 0.8
INITIAL ARAI PROP
Specific Power
35 Li t / Cyl
(kW/Ltr)
25
Indian Cars Indian MUVs
15
0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8
Ltr / Cyl
170 CAR MUV
20
150
18
130 Indian MUVs 16
110 14
BMEP (bar)
Specific Torque
(Nm/Ltr)
90 12
10
70 8
Indian Cars
50
0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8
10
Ltr/ Cyl

11. BENCH MARKING (BMEP)
25 World-wide trend of
CAR LCV
HCV
BMEP
LDV
Maximum bmep
20
15
10
0 0.5 1 2 3
Displacement / Cylinder
170 20
170
150
150
130 16
130
BMEP (bar)
110
110
bmep (bar)
9090
12
7070
50
50
8
0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8
Vehicles sold in India 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8
Ltr / Cyl l
Ltr/ C y
11

12. BENCH MARKING (BSFC)
World-wide trend
240
CAR / LCV /
LDV HCV
220
bsfc (g/kWh)
0,5
200
180
0 1 2 3
Displacement / Cylinder
12

13. THE EFFECT OF AIR-FUEL RATIO
ON EMISSIONS

14. THE EFFECT OF ENGINE
MODIFICATIONS ON EMISSIONS

15. Exhaust Gas Recirculation

16. EGR defined

18. CLOSED LOOP ELECTRONIC FUEL
CONTROL SYSTEM

19. STRATIFIED CHARGED 2-STROKE ENGINE

20. DIRECT FUEL INJECTION

21. AIR ASSISTED FUEL INJECTION

22. OCP 2-STROKE ENGINE

24. Gasoline Direct Injection

26. CARBON CANISTER

27. Catalytic Converter Diesel particulate Filter

28. Technology Options for a Sustainable
Environmentally Friendly Mobility

29. Gasoline Engine Technologies
•MPFI
• precise control of fuel at all operating modes
such as acceleration, idling, altitude, high and
low temperature operation and enrichment
based on load.
•3-Way Catalytic Converter
• Greatly reduces all three emissions of CO, HC
and NOx
• Close control of air fuel ratio is required
through close loop with lambda sensor
•Variable Valve Timing - VVT
• Improvement in fuel consumption
• optimizes intake and exhaust valve
actuation
• added torque
• reduces internal pumping losses
• reduces production of the pollutant Nox
•EGR helps to reduce NOx.
•OBD helps warning the user of
malfunctioning of the system and its

30. Gasoline Engine Technology Development
•Fuel Cells
•Electric/ Electric-
•Direct
Hybrid
BS V ? in-cylinder injection
•Multi-brick
BSIV catalytic converter
•Fuel injection + (CC+UF)
catalytic converter
(CC/UF) •Lean burn, OBD
•Variable EGR
BSIII
•Variable valve timing
•Fuel injection
•Multi valve
•3-W Catalytic
converter (pt/rh) •CNG / LPG
BSII
•Fixed EGR
•CNG / LPG
•MPFI System Development
BSI •PCV
Systems Deve
•O2 sensor
•Knock Sensor
•2-Way/ 3-Way Cat.
Con.

31. Thank You
….