AU25301 Automotive Engines – Semester III – Auto – R-2025

Subject Code & Name: AU25301 – Automotive Engines

Regulation: R-2025

Semester: III (Third Semester)

Branch: B.E. Automobile Engineering (Auto)

Credits / L-T-P: 4 Credits | L-T-P: 3-0-2

Course Objectives

• The course provides an understanding of the fundamentals, components, and operating cycles of internal combustion engines, along with fuel supply and ignition systems of SI and CI engines.
• It also covers combustion processes and the importance of cooling and lubrication systems for efficient engine operation.

Full Unit-wise Syllabus

Unit I – Engine Fundamentals

Introduction – Classification of IC Engines – Engine Terminology – Engine Components and Materials – Working Principles of SI and CI Engines –Comparison of SI and CI Engines–Two-Stroke and Four-Stroke SI Engines – Two-Stroke and Four-Stroke CI Engines – Valve Timing and Port Timing Diagrams – Fuel–Air Cycle and Actual Cycle Analysis.

Practical: Study of IC Engine Components & Materials (Identification of multi cylinder block, head, piston, connecting rod, valves, crankshaft). -Draw Valve timing diagram for 4-stroke SI & CI engines-Draw Port timing diagram for 2-stroke SI & CI engines.

Unit II – Fuel Supply and Ignition System

SI Engine: Air – Fuel ratio, Air Filters, throttle, Simple Carburetor – Injection systems – Single point and Multipoint fuel injection – Gasoline Direct Injection. Ignition System – Battery Ignition System – Electronic Ignition Systems, Laser Ignition basics. CI Engine: Jerk type fuel injection pump – Distributor type fuel injection pump. Common rail direct injection system – Fuel injector.

Practical: Dismantling and detailed study of major components followed by reassembly of a multi-cylinder petrol engine. Dismantling and detailed study of major components followed by reassembly of a multi-cylinder diesel engine.

Unit III – Combustion in SI Engines

Basic Fuel Properties of Gasoline – Combustion Process – Stages of Combustion, Flame Propagation, Flame Velocity, and Flame Front Area – Rate of Pressure Rise and Cycle-to-Cycle Variations – Abnormal Combustion: Ignition Delay, Knocking, and Detonation – Influence of Engine Operating and Design Parameters on Combustion.

Practical: Study of MPFI Engine (Dismantle & Assembly)

Unit IV – Combustion in CI Engines

Importance of Air Motion – Swirl, Squish, and Tumble – Swirl Ratio – FuelAir Mixing – Stages of Combustion – Delay Period and Factors Affecting Delay – Knock in CI Engines and Methods of Controlling Diesel Knock – CI

Unit V – Engine – Combustion Chambers

Types and Factors Influencing Combustion Chamber Design.

Practical: Study of CRDI Engine (Dismantle & Assembly)

Unit VI Engine Subsystem and Advanced Technologies

Engine Subsystem: Types of Cooling Systems – Properties of Coolants – Crankcase Ventilation – Engine Lubrication, Supercharging and Turbocharging. Advanced Technologies: Stratified charge engine, LHR, HCCI and RCCI Engines

Practical: Performance Test on a 4-Stroke Diesel Engine and Petrol engine.

Activities: Tasks T1. A car shows low mileage and reduced power – analyze causes and suggest improvements. T2. A diesel engine has cold starting issues – identify reasons and propose solutions. T3. A petrol engine experiences knocking at high speeds – analyze and reduce it. T4. An engine overheats in traffic conditions – diagnose and suggest remedies.

Course Outcomes (COs)

• CO1: Explain the basic principles of thermodynamics and energy interactions in engineering systems.
• CO2: Apply thermodynamic laws to analyze air standard cycles and steam power cycles.
• CO3: Analyse refrigeration, air conditioning systems, and heat transfer processes including conduction, convection and radiation.
• CO4: Demonstrate problem solving skills in real world thermodynamic and heat transfer applications, including performance evaluation and design calculations.

Assessment Pattern (Quick Note)

• Weightage: Continuous Assessment 50% | End Semester Examinations 50%
• Internal methodology: Written Test (40%), Practical (30%), Activity (30%). Practical: Lab Experiments (50%), Tasks (50%) (Each student must complete a minimum of two tasks). Activity: Review of GATE/ESE (10%), Mini Project/ Quiz/ Assignment Programs/ Flipped Class /Seminar Presentation (20%)

Source: Official Anna University – B.E. Automobile Engineering R-2025 Syllabus
Last Updated: September 2026