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INTRODUCTION TO AUTOMOTIVE ENGINES Instructor: Engr.Muhammad Zulfiqar Education: MS. (Mechanical ) : National University of Science and Technology (NUST) Islamabad. BS. (Mechanical) : HITEC University Taxila.

7/31/20193 Quizzes/Assignments 20% One Hour Test 30% Project Presentation 10% Final Examination 40% Grading Policy

7/31/20194 internal_combustion_engines_ fundamentals by heywood. Internal_Combustion_Engines_(Applied_Thermosciences 2e by Colin_R._Ferguson_&_Allan_T._Kirkpatrick- Reference Books

FUNDAMENTALS OF INTERNAL COMBUSTION ENGINES

HISTORY OF ICE JJ LENOIR (1860) PIONEER OF IC ENGINE NICOLAUS OTTO & EUGENE LANGEN(1876) SI ENGINES RUDOLF DIESEL(1897) CI ENGINES

INTERNAL COMBUSTION ENGINES The internal combustion engine is a heat engine that converts chemical energy in a fuel into mechanical energy, usually made available on a rotating output shaft. Chemical energy of the fuel is first converted to thermal energy by means of combustion or oxidation with air inside the engine. This thermal energy raises the temperature and pressure of the gases within the engine, and the high-pressure gas then expands against the mechanical mechanisms of the engine.

INTERNAL COMBUSTION ENGINES This expansion is converted by the mechanical linkages of the engine to a rotating crankshaft, which is the output of the engine. The crankshaft, in turn, is connected to a transmission and/or power train to transmit the rotating mechanical energy to the desired final use.

CLASSIFICATION OF INTERNAL COMBUSTION ENGINES VARIOUS TYPES OF ENGINES

ENGINE CLASSIFICATION

CLASSIFICATION OF INTERNAL COMBUSTION ENGINES 1.Application 2.Basic Engine Design 3.Working Cycle 4.Fuel 5.Mixture Preparation 6.Ignition 7.Combustion Chamber Design 8.Method of Load Control 9.Cooling

Application 1.Automotive: Car, Truck/Bus, Off-highway 2.Locomotive 3.Light Aircraft 4.Marine: Outboard, Inboard, Ship 5. Power Generation: Portable (Domestic), Fixed 6. Agricultural: Tractors, Pump sets 7. Earthmoving: Dumpers, Tippers, Mining Equipment 8.Home Use: Lawnmowers, Snow blowers, Tools 9.Others

Basic Engine Design 1. Reciprocating (a) Single Cylinder (b) Multi-cylinder (I) In-line (ii) V (iii) Radial (iv) Opposed Cylinder (v) Opposed Piston 2. Rotary: (a) Single Rotor (b) Multi-rotor

Types of Reciprocating Engines

V Engine

Working Cycle (Strokes) 1.Four Stroke Cycle a. Naturally Aspirated b. Supercharged/Turbocharged 2.Two Stroke Cycle: a. Crankcase Scavenged b. Uniflow Scavenged

Fuel 1. Conventional: a. Crude oil derived : Petrol, Diesel, Kerosene b. Other sources: Coal, Wood (includes bio-mass), Tar Sands, Shale 2. Alternate: a. Petroleum derived: CNG, LPG b. Bio-mass Derived: Alcohols (methyl and ethyl), Vegetable oils, Producer gas and biogas, Hydrogen 3. Blending 4. Multi-Fuel Engines

Mixture Preparation 1.Carburetion 2.Fuel Injection(i) Diesel (ii) Gasoline (a) Manifold (b) Port (c) Cylinder

Ignition 1.Spark Ignition (a) Conventional (i)Battery (ii)Magneto (b) Other methods 2.Compression Ignition

Combustion Chamber Design 1. Open Chamber: Disc type, Wedge, Hemispherical Bowl-in-piston 2.Divided Chamber: For CI: Swirl chamber, Pre-chamber For SI: Compound vortex controlled combustion (CVCC)

Method of Load Control 1.Throttling: To control mixture strength. Also called Charge Control. Used in Carbureted S.I. Engines 2.Fuel Control: To vary the mixture strength according to load. Used in the C.I. Engine 3. Combination. Used in Throttle body Fuel-injected S.I. Engine.

Cooling 1.Direct Air-cooling 2.Indirect Air-cooling (Liquid Cooling) 3.Low Heat Rejection (Semi-adiabatic) engine.

INTERNAL COMBUSTION ENGINES

ENGINE PARTS

INTERNAL COMBUSTION ENGINES

SI ENGINES

INTERNAL COMBUSTION ENGINES BASIC FUNCTIONRECIPROCATING ENGINES

INTERNAL COMBUSTION ENGINES Advantages MECHANICAL SIMPLICITY IMPROVED THERMAL EFFICIENCY DON’T NEED AUXILLARY EQUIPMENT SHORT START AND STOP TIME LOW INITIAL COST EFFICENT PERFORMANCE Disadvantages FUEL COST WORKING FLUID ONLY LIQUID OR GASEOUS AT GIVEN SPECIFICATIONS VIBRATION PROBLEMS

ENGINE COMPONENTS

INTERNAL COMBUSTION ENGINES

CRANK SHAFT

CYLINDER BLOCK

PISTONS

CONNECTING RODS

CAM SHAFTS

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