Lecture

Internal Combustion Engines: Otto and Diesel Cycles

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

In course

PHYS-106(h): General physics : thermodynamics

Le but du cours de Physique générale est de donner à l'étudiant les notions de base nécessaires à la compréhension des phénomènes physiques. L'objectif est atteint lorsque l'étudiant est capable de prévoir quantitativement les conséquences de ces phénomène ...

Description

This lecture covers the principles and operation of two internal combustion engines: the Otto cycle and the Diesel cycle. The Otto cycle, named after its inventor Niklaus Otto, is analyzed in detail, focusing on the six phases involved in the cycle. The lecture explains the assumptions made to calculate the theoretical efficiency and discusses the factors influencing the compression ratio. Moving on to the Diesel cycle, the lecture explores how it differs from the Otto cycle, emphasizing the higher compression ratio and efficiency. The disadvantages of the Diesel cycle, such as increased weight due to higher pressure and temperature requirements, are also discussed. The lecture concludes by posing a question to the audience regarding the CO2 emissions produced by diesel and gasoline engines per kilometer.

Instructor

Ivo Furno

Teaching & PhD PhD Students Jules Amédée Aristobule Schadt, Renat Karimov, Amélie Renggli, Yuri Asnis, Michael Goddijn, Vanni Jonas Meier, Cyrille Sepulchre, Francesco D'Angelo Past EPFL PhD Students Federico Nespoli, Oulfa Chellai, Thibaut François Hugo Richard, Fabian Manke, Riccardo Agnello, Alexandra Waskow, Lorenzo Ibba, Agus Rita, Kadi Lyes Roland Past EPFL PhD Students as codirector Davoud Iraji, Christian Gabriel Theiler, Alexandre Dominique Bovet, Fabio Avino Courses General physics : thermodyn

Official source

Related concepts (15)

Four-stroke engine

A four-stroke (also four-cycle) engine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either direction. The four separate strokes are termed: Intake: Also known as induction or suction. This stroke of the piston begins at top dead center (T.D.C.) and ends at bottom dead center (B.D.C.).

Thermal efficiency

In thermodynamics, the thermal efficiency () is a dimensionless performance measure of a device that uses thermal energy, such as an internal combustion engine, steam turbine, steam engine, boiler, furnace, refrigerator, ACs etc. For a heat engine, thermal efficiency is the ratio of the net work output to the heat input; in the case of a heat pump, thermal efficiency (known as the coefficient of performance) is the ratio of net heat output (for heating), or the net heat removed (for cooling) to the energy input (external work).

Diesel cycle

The Diesel cycle is a combustion process of a reciprocating internal combustion engine. In it, fuel is ignited by heat generated during the compression of air in the combustion chamber, into which fuel is then injected. This is in contrast to igniting the fuel-air mixture with a spark plug as in the Otto cycle (four-stroke/petrol) engine. Diesel engines are used in aircraft, automobiles, power generation, diesel–electric locomotives, and both surface ships and submarines.

Diesel engine

The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is called a compression-ignition engine (CI engine). This contrasts with engines using spark plug-ignition of the air-fuel mixture, such as a petrol engine (gasoline engine) or a gas engine (using a gaseous fuel like natural gas or liquefied petroleum gas).

Internal combustion engine

An internal combustion engine (ICE or IC engine) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is typically applied to pistons (piston engine), turbine blades (gas turbine), a rotor (Wankel engine), or a nozzle (jet engine).

Related lectures (55)

Thermodynamics: Internal Combustion Engine Cycles MOOC: Thermodynamics I

Discusses thermodynamics in internal combustion engines, focusing on the four-stroke cycle and comparing Otto and Diesel cycles.

Thermodynamics: Otto and Diesel Engine Cycles

Explains the thermodynamic principles of Otto and Diesel engine cycles, including their efficiencies and applications in automotive engineering.

Thermal Machines: Other Cycles

Explores thermal cycles in engines and heat pumps, including historical machines and power cycles.

Diesel Engine: Thermodynamic Cycle

Covers the thermodynamic cycle of a Diesel engine and its efficiency.

Combustion: Fundamentals and Applications