🗊Презентация Internal сombustion engine basics, components, systems, construction, test and perspectives

Internal Сombustion Engine

Aleksey Terentyev Contact Information: Izhevsk State Technical University, 7 Studencheskaya street, Building 2, Room 415 426069, Izhevsk, Russia Office phone: 7 (3412) 77-31-59 Internal office phone: 23-02 Mobile phone 8-912-752-29-47 E-mail: tdu_teran@mail.ru Personal data: Education Izhevsk State Technical University (OF ISTU) 10.1993 – 02.1999 Specialty: Engineer-mechanic-Engine Construction and Test Post graduate course at the Izhevsk State Technical University (of ISTU) 03.1999 – 05.2005 Outcome: PhD degree in Technique – «Noise and Vibration of the Car» Position An associate professor at the Izhevsk State Technical University named after Mikhail Kalashnikov Date of Birth: 30.11.1975 Work experience: from 1999

What is an Engine?

1.Types of Power Plants Heat engine can be broadly classified into two categories: (a) Internal Combustion Engines (an abbreviation ICE); (b) External Combustion Engines (an abbreviation ECE)

1.1. Classification of Heat Engines Engines whether Internal Combustion or External Combustion are of two types: (I) Rotary engines (II) Reciprocating engines

1.2. Classification of Internal combustion Engines (an abbreviation ICE) There are many different types of internal combustion engines. They can be classified by their: 1. Application. Automobile, truck, locomotive, light aircraft, marine, etc. 2. Basic engine design. Reciprocating engines (in-line, V, opposed), rotary engines (Wankel) 3. Working cycle. Four-stroke cycle: naturally aspirated (admitting atmospheric air), supercharged (admitting precompressed fresh mixture), and turbocharged (admitting fresh mixture compressed in a compressor driven by an exhaust turbine), two-stroke cycle: crankcase scavenged, supercharged, and turbocharged 4. Valve or port design and location. Overhead (or I-head) valves, underhead (or L-head) valves, rotary valves, cross-scavenged porting (inlet and exhaust ports on opposite sides of cylinder at one end), loop-scavenged porting (inlet and exhaust ports on same side of cylinder at one end), through- or uniflowscavenged (inlet and exhaust ports or valves at different ends of cylinder) 5. Fuel. Gasoline (or petrol), fuel oil (or diesel fuel), natural gas, liquid petroleum gas, alcohols (methanol, ethanol), hydrogen, dual fuel

1.2. Classification of Internal combustion Engines (ICE) 6. Method of mixture preparation. Carburetion, fuel injection into the intake ports or intake collector, fuel injection into the engine cylinder 7. Method of ignition. Spark ignition (in conventional engines where the mixture is uniform and in stratified-charge engines where the mixture is non-uniform), compression ignition (in conventional diesels, as well as ignition in gas engines by pilot injection of fuel oil) 8. Combustion chamber design. Open chamber (many designs: e.g., disc, wedge, hemisphere, bowl-in-piston), divided chamber (small and large auxiliary chambers; many designs: e.g., swirl chambers, prechambers) 9. Method of load control. Throttling of fuel and air flow together so mixture composition is essentially unchanged, control of fuel flow alone, a combination of these 10. Method of cooling. Water cooled, air cooled, uncooled (other than by natural convection and radiation) All these distinctions are important and they illustrate the breadth of engine designs available.

2. Basic Geometry of the Reciprocating Internal Combustion Engine (an abbreviation RICE)

3. Main Components and Principle of Operation of the Internal Combustion Engine

4. The Four-Stroke Petrol Engine Cycle

How does this work ?

4.1 Inlet Stroke To describe the complete cycle, let's assume that the piston is at the top of the stroke (top dead center) and the inlet and the exhaust valves are closed. When the piston moves down the inlet valve opens to intake a charge of fuel into the cylinder

So the piston moves in the cylinder down (intake stroke), up (compression stroke), down (power stroke), up (exhaust stroke) and after the cycle is repeated

Four-stroke CI Engines 1.Suction stroke Only air is inducted during the suction stroke. During this stroke intake valve is open and exhaust valve is closed. 2.Compression stroke Both valves remain closed during compression stroke. 3. Expansion or power stroke Fuel is injected in the beginning of the expansion stroke. The rate of injection is such that the combustion maintains the pressure constant. After the injection of fuel is over (i.e. after fuel cut off) the products of combustion expand. Both valves remain closed during expansion stroke. 4. Exhaust stroke. The exhaust valve is open and the intake valve remains closed in the exhaust stroke. Due to higher pressures the CI engine is heavier than SI engine but has a higher thermal efficiency because of greater expansion. CI engines are mainly used for heavy transport vehicles, power generation, and industrial and marine applications.

6. Two-stroke Cycle Engines – Principle of operation In two-stroke engines the cycle is completed in two strokes, that is, one revolution of the crankshaft as against two revolutions of four-stroke cycle. The difference between two-stroke and four-stroke engines is in the method of filling the cylinder with the fresh charge and removing the burned gases from the cylinder.

Two-Stroke Cycle The air or charge is sucked through spring-loaded inlet valve when the pressure in the crankcase reduces due to upward motion of the piston during compression stroke. After the compression, ignition and expansion takes place in the usual way: during the expansion stroke the air in the crankcase is compressed. Near the end of expansion stroke piston uncovers the exhaust port, and the cylinder pressure drops to atmospheric as the combustion products leave the cylinder. Further motion of the piston uncovers transfer ports, permitting the slightly compressed air or mixture in the crankcase to enter the engine cylinder. The top of the piston sometimes has a projection to deflect the fresh air to sweep up to the top of the cylinder before flowing to the exhaust ports. This serves the double purpose of scavenging the upper part of the cylinder of combustion products and preventing the fresh charge from flowing directly to the exhaust ports. The same objective can be achieved without piston deflector by proper shaping of the transfer port. During the upward motion of the piston from bottom dead centre, the transfer ports and then the exhaust port close and compression of the charge begins and the cycle is repeated.

7. SI Engine Components

8. CI Engine Components