2. Further Analysis of Otto’s Ideal Model P M V Subbarao Professor Mechanical Engineering Department Deeper understanding of Issues related t Practicablity …

3. Ideal Otto Cycle

4. Net cycle work: Analysis of Otto Cycle

5. Clue to Achieve Higher Efficiency r

6. Hardware Feasibility of Otto Cycle Net cycle work: Piston Displacement volume Work done per unit piston displacement volume:

7. Measure of Size & Feasibility P V2V2 V1V1 Q in W cycle 1 2 3 4 AIR

8. The net cycle work of an engine can be increased by either: i) Increasing the r (1  2’) P V2V2 V1V1 Q in W cycle 1 2 3 4 Factors Affecting Work per Cycle (i) 2’ 3’ C (ii) 4’’ 3’’ ii) Increase Q in (2  3”) 4’ C

9. SI Engine for Propulsion

10. Thermo-chemical Feasibility Fuel/Air Mixture Compression Stroke

11. 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

12. Critical Compression Ratio FormulaName Critical r CH 4 Methane12.6 C 3 H 8 Propane12.2 C 8 H 18 Isooctane 7.3

13. 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 Oregon Worst recorded fire in state's history. [8] [8] 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.Great Chicago Fire

14. Generalized Flammability Map

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

16. Spontaneous (Auto) Ignition Temperature of Fules Fuel SIT,  C Petrol246 -- 280 Diesel210 Kerosene295 Natural Gas580 Hydrogen500 Iso-Octane447 Iso-Butane462

17. Rudolf Christian Karl Diesel Diesel published a treatise entitled, 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. In his engine, fuel was injected at the end of compression and the fuel was ignited by the high temperature resulting from compression.

18. A brief history of the diesel engine 1897 -- Diesel built the first diesel engine at the Augsburg Maschinenfabrik. 1898 -- 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. 1922 Benz introduces a 2-cylinder, 30 hp 800 rpm tractor engine. 1924 Benz introduces a 4-cylinder, 50 hp 1000 rpm truck engine. 1960- 1970 Peugeot introduces the 404 Diesel followed by the 504 Diesel and the 204 Diesel, the first diesel-powered compact car

19. Displacement Work Devices : Compression Ignition Engine A I R Intake Stroke Power Stroke Air Compression Stroke Combustion Products Exhaust Stroke

20. Air Compression Process Expansion Process BC Q out Const volume heat rejection Process Q in Const pressure heat addition Process Ideal Diesel Cycle