Presentation is loading. Please wait.

Presentation is loading. Please wait.

P M V Subbarao Professor Mechanical Engineering Department

Similar presentations


Presentation on theme: "P M V Subbarao Professor Mechanical Engineering Department"— Presentation transcript:

1 P M V Subbarao Professor Mechanical Engineering Department
20th Century Inventions for Automotive Prime Movers based on Diesel’s Model P M V Subbarao Professor Mechanical Engineering Department Methods of Building a Rational & Powerful Artificial Horse….

2 Thermo-chemical Feasibility of Otto’s Model

3 Thermo-chemical Feasibility of Ignition at Low Loads

4 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

5 Critical Compression Ratio
Formula Name Critical r CH4 Methane 12.6 C3H8 Propane 12.2

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

7 Flame Quenching at Wall

8 Rudolf Christian Karl Diesel
Diesel was born in Paris, France in 1858 the second of three children of Elise and Theodor Diesel. At age 14, Rudolf wrote a letter to his parents stating that he wanted to become an engineer. After finishing his basic education at the top of his class in 1873, he enrolled at the newly-founded Industrial School of Augsburg. Two years later, he received a merit scholarship from the Royal Bavarian Polytechnic of Munich, which he accepted against the wishes of his parents, who would rather have seen him start to work.

9 Diesel was graduated in January 1880 with highest academic honours and returned to Paris, where he assisted his former Munich professor, Carl von Linde, with the design and construction of a modern refrigeration and ice plant. Diesel became the director of the plant one year later. In early 1890, Diesel moved to Berlin. Diesel understood thermodynamics and the theoretical and practical constraints on fuel efficiency. He first worked with steam, his research into thermal efficiency and fuel efficiency leading him to build a steam engine using ammonia vapour. During tests, however, the engine exploded and almost killed him. He spent many months in a hospital, followed by health and eyesight problems.

10 He then began designing an engine based on the Carnot cycle, and in 1893, Diesel published a treatise entitled Theorie und Konstruktion eines rationellen Wärmemotors zum Ersatz der Dampfmaschine und der heute bekannten Verbrennungsmotoren. 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.

11 Early Diesel’s Engine Cycle and the Thermodynamic Model
Fuel injected at TC Power Stroke A I R Intake Stroke Combustion Products Exhaust Stroke Air Compression Stroke Actual Cycle Qin Const pressure heat addition Process BC Qout Const volume heat rejection Process Air Compression Process Expansion Process Diesel Cycle

12 Thermal Efficiency 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

13 Structure of Efficient Diesel Cycle
Higher efficiency is obtained by adding less heat per cycle, Qin,  run engine at higher speed to get the same power.

14 Multi Cylinder diesel 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. 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

15 Care for Occurrence of Heat Addition
Occurrence of Heat Addition in SI Engine : A Child Care Event. Occurrence of Heat Addition in CI Engine: A Teen Care Event. CI Engine SI Engine

16 The Complex Nature of Young Teen & Solutions

17 Schematic of a diesel spray & flame with temperatures and chemistry

18 Onset of The Inevitable Danger

19 Development of Injection Pressure & Injection System in CI Engines

20 Common Rail Diesel Injection System
The Common Rail Diesel Injection System delivers a more controlled quantity of atomised fuel, which leads to better fuel economy; a reduction in exhaust emissions; and a significant decrease in engine noise during operation.

21 CI Religion in I.C. Engines
Diesel Engines  High CR  No throttling , quality governed,  High fuel economy at part load Low specific power  Low grade fuel, heterogeneous combustion  Turbo-charging – not useful for small engines High NOx and Smoke

22 Emission standards for diesel heavy duty engines
Year Reference CO, (g/kW-hr) HC, (g/kW-hr) NOx, (g/kW-hr) PM, (g/kW-hr) 1992 - 1996 11.20 2.40 14.4 2000 Euro I 4.5 1.1 8.0 0.36 2005† Euro II 4.0 7.0 0.15 2010† Euro III 2.1 0.66 5.0 0.10 2010‡ Euro IV 1.5 0.46 3.5 0.02 † earlier introduction in selected regions, Table 1 ‡ only in selected regions, Table 1

23 Current CI Religion in I.C. Engines
Diesel Engines  High CR  No throttling , quality governed,  High fuel economy at part load Low specific power  Low grade fuel, heterogeneous combustion  Turbo-charging – not useful for small engines High NOx and Smoke

24 A Model for Secular I.C. Engines
The Right Engine High power at full load  Homogeneous charge, high CR, high vol. High Fuel economy  Distinctly stratified charge, avoidance of throttling losses, quality governing Lower HC..


Download ppt "P M V Subbarao Professor Mechanical Engineering Department"

Similar presentations


Ads by Google