1. 19th & Early 20th Century CI Models for Automotive Prime Mover
P M V Subbarao
Professor
Mechanical Engineering Department
Zero to First Generation Rational Technologies for Artificial Horse…..

2. Engine Damage From Severe Knock
Damage to the engine is caused by a combination of high temperature and high pressure.
Piston
Piston crown
Cylinder head gasket
Aluminum cylinder head

3. Thermo-chemical Feasibility of Ignition
Saturation line
Upper Flame Limit
Vapour Pressure in Air
Piloted Ignition Region
Onset of
Lower Flame Limit
Mixture Temperature

4. Design Constraints: Flammability Characteristics
Rich Mixture
Stoichiometric Line
Flammable mist
Flammable Vapour
Flash Point
Lean Mixture Line
Burning Impossible
Mixture Temperature

5. Irrationality of Otto’s Model
Typical SI engines
9 < r < 11
k = 1.4
Fuel/Air
Mixture
Compression
Stroke

6. Flame Quenching at Wall

7. Live with A Promising Irrational Engine Model????
Advanced Cities
Generation of
photochemical smog
Artificial Horses
eye and respiratory irritation in humans
epinasty, chlorosis, curling, leaf abscission and growth retardation in plans

8. History of Wildfires 1825 3,000,000 acres Miramichi Fire New Brunswick
Killed 160 people.
1853
482,000 acres
Yaquina Fire
Oregon
1865
1,000,000 acres
Silverton Fire
Worst recorded fire in state's history.
1870
964,000 acres
Saguenay Fire
Quebec
1871
1,200,000 acres
Peshtigo Fire
Wisconsin
Killed over 1,700 people and has distinction of the conflagration that caused the most deaths by fire in United States history. It was overshadowed by the Great Chicago Fire that occurred on the same day.

9. Thermo-chemical Feasibility of Ignition
Saturation line
Upper Flame Limit
Vapour Pressure in Air
Piloted Ignition Region
Automatic Ignition Temperature
Hot Surface Ignition Region
Lower Flame Limit
Mixture Temperature

10. Design Constraints: Flammability Characteristics
Rich Mixture
Stoichiometric Line
Spontaneous Ignition
Flammable mist
Flammable Vapour
Inflammable mist
Flash Point
Lean Mixture Line
Burning Impossible
Mixture Temperature

11. Inflammability of Fuels

12. Spontaneous (Auto) Ignition Temperature of Fules
Fuel
SIT, C
Petrol
Diesel
210
Kerosene
295
Natural Gas
580
Hydrogen
500
Iso-Octane
447
Iso-Butane
462

13. Diesel’s Rational Engine
Theory and Construction of a Rational Heat-engine to Replace the Steam Engine and Combustion Engines Known Today.
This formed the basis for his work on and invention of, the diesel engine.
Eventually he obtained a patent for his design for a compression-ignition engine.
In his engine, fuel was injected at the end of compression and the fuel was ignited by the high temperature resulting from compression.

14. Air-Standard Diesel cycle
Process 1 2 Isentropic compression
Process 2  3 Constant pressure heat addition
Process 3  4 Isentropic expansion
Process 4  1 Constant volume heat rejection
Compression-ratio:
Cut-off ratio:

15. 19th Century CI engines
Diesel built the first diesel engine at the Augsburg Maschinenfabrik .
Rudolph Diesel, filed a patent application
The single cylinder engine was used to power stationary machinery.
It weighed five tonnes and produced 20 hp at 172 rpm!
The engine operated at 26.2% efficiency, a very significant improvement on the 20% achieved by the best gasoline engines of the time.

16. Thermal Efficiency of Diesel Engine Model
rc=1
rc=2
Typical CI Engines
15 < r < 20
rc=3
When rc (= v3/v2)1 the Diesel cycle efficiency approaches the efficiency of the Otto cycle

17. The world’s biggest engine : Wärtsilä-Sulzer RTA96. :May 2015
14-cylinder, 2-stroke turbocharged Diesel engine.
Weight : 2.3 million kgs
Speed : 102 rpm
powering the Emma Maersk
It has now become cheaper to transport goods from China to a US port than to transport the same goods from a US port to the final destination inland of US by a truck.

18. Early 20th Century CI engines
High-speed diesel engines were introduced in the 1920s for commercial vehicle applications and in the 1930s for passenger cars.
1922 Benz introduces a 2-cylinder, 30 hp 800 rpm tractor engine.
1924 Benz introduces a 4-cylinder, 50 hp 1000 rpm truck engine.
Peugeot introduced the 404 Diesel followed by the 504 Diesel and the 204 Diesel, the first diesel-powered compact car

19. Dual Nature of Combustion in High Speed Diesel Engines
Air TC BC
Qin
Qout
Compression
Process
Const pressure
heat addition
Expansion
Const volume
heat rejection
Dual
Cycle
Thermodynamic Dual Cycle

20. Dual Cycle Process 1  2 Isentropic compression
Process 2  2.5 Constant volume heat addition
Process 2.5  3 Constant pressure heat addition
Process 3  4 Isentropic expansion
Process 4  1 Constant volume heat rejection 3
Qin
2.5 3 2
Qin
2.5 4 2 4 1 1
Qout

21. Thermal Efficiency of Dual Cycle
Note, the Otto cycle (rc=1) and the Diesel cycle (a=1) are special cases:

22. The use of the Dual cycle requires information about either:
the fractions of constant volume and constant pressure heat addition (common assumption is to equally split the heat addition), or
maximum pressure P3.
Transformation of rc and a into more natural variables yields
For the same inlet conditions P1, V1 and the same compression ratio:
For the same inlet conditions P1, V1 and the same peak pressure P3
(actual design limitation in engines):

23. For the same inlet conditions P1, V1 and the same peak pressure P3:
For the same inlet conditions P1, V1 and the same compression ratio P2/P1:
For the same inlet conditions P1, V1
and the same peak pressure P3:
Diesel
Dual
Otto
Pmax
Tmax Po
Pressure, P
Temperature, T
Specific Volume
Entropy
Diesel
Dual
Otto
“x” →“2.5” Po
Pressure, P
Temperature, T
Specific Volume
Entropy