Internal Combustion Engines

24-421, Fall 2017

Satbir Singh


Experimental imaging of diesel combustion in a transparent engine


Lecture:

Day and Time: Tuesday and Thursday, 1:30 - 2:50 pm
Location: SH 220

Instructor Office Hours:

Time: Tuesday, 4:00 - 5:00 pm
Location: Scaife Hall 319


TA Office Hours:

Time: Wednesdays, 5:00 - 6:00 PM
Location: MechE Computing Cluster in HH


Course Description:

This course will provide an understanding of the working principles of conventional and advanced internal combustion (IC) engines. Emphasis will be given to thermodynamic, fluid mechanic, and combustion aspects of the IC engine. After taking this course, students will be able to gain a general understanding of how combustion system configuration, in-cylinder fluid flow, chemical characteristics of fuels, engine heat transfer, and in-cylinder fuel-air mixing affect performance and pollutant emissions from automotive and heavy-duty type IC engines. Students will perform three experimental labs that involve engine teardown, collection of performance and pollutant emissions data from a multi-fuel variable compression ratio gasoline engine. Students will also perform simulations of a diesel engine combustion system using computational fluid dynamics (CFD).

Prerequisites: Thermodynamics, Fluid Mechanics or equivalent

Textbook:
  • Internal Combustion Engine Fundamentals, John Heywood
Grading:
  • Homework (40%)
  • Experimental lab (15%)
  • Engine CFD team project (15%)
  • Exam 1 (15%)
  • Exam 2 (15%)
Tentative Syllabus Outline: ---------------------------------------------------------------------
Aug 28 - Dec 08 (15 weeks)
---------------------------------------------------------------------
Week 1 Introduction and Operating Principles
History of IC engines, arrangement of pistons, 2-stroke vs 4-stroke cycles, types of combustion systems
Week 2 Geometric and Performance Parameters
Engine geometric terminology, relationship of crank and piston motions, introduction to important performance parameters
Week 3 Intake System and Air Handling
Valve arrangement, valve motion and timing, various losses in intake system, volumetric efficiency, factors affecting volumetric efficiency, intake charge boosting (supercharger vs turbocharger)
Week 4 Fuels and Thermochemistry
Engine fuels and their chemical characteristics, chemistry of combustion reactions, calculation of fuel heating value, maximum flame temperature, engine exhaust gas analysis
Week 5 Thermodynamic Analysis of Engine Cycles
Air-standard Otto and Diesel cycles, Brayton cycle, comparison of ideal and real cycles, introduction to over-expanded cycle, maximum possible work
Week 6 Spark Ignited (SI) Engine Combustion
Fuel metering and mixture preparation, spark ignition, flame development, abnormal combustion, effect of engine parameters on performnace and knock
Week 7 Compression Ignited (CI) Engine Combustion
Combustion system configurations, fuel injection, spray breakup, different phases of diesel combustion, flame structure, burning rate analysis
Week 8 Fluid Mechanic Interaction with Combustion-I
Turbulence generation, tumbling and swirling flows
Oct 19 Exam 1
Week 9 Fluid Mechanic Interaction with Combustion-II
Coupling of in-cylinder flow and combustion, concepts of laminar and turbulent burning speeds

Pollutant Formation and Control
Types of pollutants, sources of pollutants in SI and CI engines, technologies to mitigate pollutant formation, treatment of exhaust gas
Week 10 Introduction to Advanced Engine Concepts
Gasoline direct injection engines, HCCI engines, dual-fuel engines, introduction to hybrid vehicles, series vs parallel hybrid systems
Week 11 Computer Simulations of IC Engines
Purpose of simulations, phenomenological models for SI and diesel engine combustion, introduction to engine CFD analysis, Training to setup diesel engine combustion analysis in commercial CFD software. After this training, students will be able to work on computational project.
Week 12 Engine Heat Transfer
Energy flow in IC engine, various modes of heat transfer, effect of heat transfer on engine efficiency at various speeds and loads

Waste Heat Recovery from IC Engines
Thermodynamic analysis of energy balance, introduction of Sterling engine and thermoelectrics for heat recovery
Week 13 Engine Operating Characteristics and Performnace
Various powers vs RPM, effect of spark timing and fuel/air ratio on power and efficiency, effect of EGR on effieicny and MBT timing, effect of compression ratio and engine size on efficiency, engine performance

Thanksgiving break
Week 14 Gas Turbine Engines
Brayton cycle analysis, combustor design and performance
Dec 05 CFD project presentations
Dec 07 Exam 2