Thermal Engines I

Thermodynamics, Heat Transmission, Fluid Mechanics, Materials.

Skills development through theoretical classes with discussion and theoretical-practical classes to describe engines and solve theoretical-practical exercises. Training supported by new technologies, namely internet, computer programs and audiovisual media.

Know the theoretical and practical aspects of operation, technologies, design of the main components and engine manufacturing processes. Characterize the combustion, as well as its correlation with the octane index and cetane index. Compare and distinguish the compression ratios of spark ignition and compression ignition engines. Characterize and differentiate the two-stroke and four-stroke engine distribution diagrams. Identify the different concepts and functions of the distribution and its components. Develop specialized work in terms of internal combustion engine technology. Plan and monitor the performance of third parties in the application of methodologies, techniques and advanced interventions for maintenance, repair, rectification, preparation and transformation of internal combustion engine systems.

INTRODUCTION TO THE STUDY OF HEAT ENGINES

Fundamental concepts; Classification of alternative engines; Reciprocating engine speed and load.

THEORETICAL CYCLES AND REAL CYCLES. PRESSURE DIAGRAMS

Thermal efficiency and average pressure of the cycles; Indicated cycle and indicated average pressure; Difference between real and theoretical cycles;

Diagram of pressures inside the cylinder as a function of the angular displacement of the crankshaft for 2 and 4 stroke engines; Exercises

theoretical-practical application.

FUEL, MIXTURE AND COMBUSTION

Types and properties of fuels; Composition and formation of the mixture; stoichiometric relationship; Heat released in combustion;

Start of combustion.

CHARACTERISTICS CURVES AND THERMAL BALANCE

Indicated, effective or brake power and absorbed power. Effective mean pressure. income; Thermal Balance; Performance

volumetric; Specific consumption of SI and CI engines. Stability in engine operation. Regulation and regulators. Exercises

theoretical-practical.

MAIN COMPONENTS OF AN ENGINE – FUNCTION AND MATERIALS USED IN ITS MANUFACTURE

Block and Cylinders; Head; Joint between the block and the head; combustion chamber; Valve guides and seats, clearance between guides and valves

valves and gaskets for valve guides; Pistons or pistons and segments; Piston pin or pin; connecting rod and crankshaft;

Crankshaft supports; Bronzes; Crankshaft and connecting rod bearings;

KINEMATICS AND DYNAMICS OF ALTERNATIVE ENGINES

INTRODUCTION TO VACUUM TECHNOLOGY

DISTRIBUTION

Distribution diagram and types; Camshaft control; Valves: Dimensions and stroke of valves. variation of

lifting during movement; Effect of alternating forces of inertia. Valve temperature with the engine running. materials

used in the manufacture of valves;. Sodium valves; “Touches”, clubs or impellers; clearances between valves and “touches”;

“Touches” for automatic adjustment of the gap; automatic actuators; Valve call springs; Distribution phase adjustment.

RESOLUTION OF THEORETICAL-PRACTICAL EXERCISES

• - Exame - 100.0%

• - Testes Teóricos - 100.0%

NAO

Martins, Jorge (2006). Motores de Combustão Interna. Publindústria, 2ª. Edição. ISBN 972-98726-8-6.

Arias-Paz, Manual da Técnica Automóvel, Editora Mestre Jou, ISBN: 84-89656-09-6.

Vários Autores (2003). Mecânica Automóvel. Editora Alves da Costa.

Manual do CEPRA de “Sistemas de distribuição”.

Estévez, S. (1995). Tecnologia do Automóvel, Editora Plátano.

Çengel, Yunus & Boles, Michael A. (1994). Thermodynamics, an Engineering Aproach. McGraw Hill. ISBN: 0-07-113249-X.

Lucchesi, Domenico (1989). O Automóvel – Curso Técnico, vol. 1 e 2. Editorial Presença. ISBN: 972-23-1022-4 e 972-23-1045-3.

Giacosa, Dante (1986). Motores Endotérmicos, Editorial Dossat, S.A., 3ª. Edição. ISBN: 84-237-0382-7.

Bocchi, Giuseppe. Motori a Quattro Tempi. Hoepli Editore. ISBN: 88-203-1533-5.