# Internal Combustion Engines: Theory & Practice

ICE-EN-A
This course can be adapted to virtual classroom mode

## Who should attend?

• This course provides a deeper knowledge on mechanical operations and behavior and challenges of air induction, combustion, thermodynamics, performance improvements…
Public :
• Engineers and technical staff involved in the design, development and testing of spark ignition engines and equipment.

Level : Foundation

## Course Content

• ### Thermodynamics applied to engines

• Engine history: evolution till the 4-stroke engine.
• Thermodynamics first and second principles: calculation of an exhaust temperature. Why compressing before combustion?
• Engine efficiencies: calculation of the engine best possible efficiency.
• Calculation of cylinder pressure at compression end. Internal energy, enthalpy, entropy. Ideal gas equation. Laplace equation.
• Different thermodynamic cycles (Beau de Rochas, Diesel, Atkinson, Miller, Stirling).
• Turbocharger isentropic efficiency.
• ### Performance & efficiency

• MEP: analysis of energy per cycle by mean pressure: BMEP (Brake Mean Effective pressure), IMEP (Indicated Mean Effective Pressure), FMEP (Friction Mean Effective Pressure).
• Global efficiency: analysis of the 4 main efficiencies of a reciprocating engine, fuel consumption (BSFC), impact of different settings (load, A/F ratio, ignition timing, …) on the efficiencies. Differences between the ideal cycle (Beau de Rochas) and the real cycle (thermal loss, pumping loss, …).
• Volumetric efficiency.
• Engine-vehicle adaptation: Willans diagram, fuel consumption, gear staging.
• ### Engine mechanics

• Engine acyclism: reasons why an engine does not work regularly: forces due to gas pressure and inertia of moving parts. Consequences of acyclism (belt resistance, damper pulley, double flywheel clutch - DFC).
• Balancing: use of a balancer shaft or a counterweight on a crankshaft. Inertia load due to rotary and alternative forces. Inertia load of first and second order (H1, H2) on a 4-cylinder engine.
• Valve timing: how the different valve drives work.
• Lubrication: the different lubrication modes. Viscosity. Stribeck curve.
• ### Inlet/exhaust processes - Performances & forced induction

• Fluid dynamics: Bernoulli equation, Saint Venant equation, sound velocity.
• Gas exchange and flow processes: use of pressure waves in inlet and exhaust pipes to increase the volumetric efficiency.
• Exhaust Gas recirculation (EGR): uses of EGR, low pressure EGR, high pressure EGR.
• Turbocharging: how it works, technology, turbo adaptation.
• ### Materials - Mechanical endurance

• Characteristics of metal alloy steels used in engines: grey iron, ductile iron, steel, aluminum.
• Manufacturing processes (foundry and forge). Surface treatment.
• Mechanical properties: Young’s modulus, minimum yield, shear rating. Analysis of the engine major parts whose material and manufacturing process must be chosen.
• ### Engine parts damage modes

• Due to thermal problems: carbonization, loss of mechanical characteristics, intercrystalline corrosion, creep, melting.
• Due to mechanical problems: plastic deformation, fracture, fatigue failure, Goodman diagram, impact of vibrations.
• Due to thermo-mechanical problems.
• Due to tribologic problems: lubrication, Stribeck curve, pitting, fretting, abrasive wear, adhesive wear, erosive wear, cavitation, scuffing, stick-slip.
• ### Vibrations

• Transverse vibration, Eigen mode, resonance, damping.
• Acceleration, velocity, displacement parameters. Vibration levels: amplitudes, frequencies. Spectrum decibels, harmonic number.
• Vibration measurement, sonogram, tracking.
• The above training includes many practical exercises.

## Learning Objectives

• Upon completion of the course, participants will be able to:
• calculate effective sections of a cylinder head or EGR circuit,
• understand and apply the equations used on the engine test bench,
• analyze the causes of engine component damage or failure,
• understand the vocabulary and tools used in the vibration analysis field,
• calculate and select a turbocharger to match a performance curve (turbo matching).

## Ways & Means

• All the training below includes many practical exercises to illustrate the concepts presented.
To French entities : IFP Training is QUALIOPI certified ; you may contact your OPCO about potential funding.