Internal combustion engine

**History of Internal Combustion Engines:**
– John Barber developed the gas turbine in 1791.
– Thomas Mead patented a gas engine in 1794.
– Robert Street patented the first internal combustion engine using liquid fuel in 1794.
– John Stevens built the first American internal combustion engine in 1798.
– François Isaac de Rivaz invented a hydrogen-based internal combustion engine in 1807.
– Dugald Clerk developed the first two-cycle engine in 1879.
– In 1899, John Day simplified Clerk’s design into the type of 2-cycle engine widely used today.

**Etymology and Nomenclature:**
– The word ‘engine’ originally meant any piece of machinery.
– ‘Motor’ refers to any machine producing mechanical power.
– Internal combustion engines are traditionally referred to as engines in boating.
– Engines on the transom of boats are referred to as motors.

**Applications and Uses of Internal Combustion Engines:**
– Reciprocating piston engines are common in land and water vehicles.
– Wankel rotary engines are used in some automobiles, aircraft, and motorcycles.
– Combustion turbines and Wankel engines provide high power-to-weight ratios.
– ICEs power aircraft, helicopters, and large electric generators.
– Combined cycle power plants achieve efficiencies of 50-60%.
– ICEs are used in vehicles like automobiles, motorcycles, ships, and aircraft.

**Types and Classification of Internal Combustion Engines:**
– By number of strokes: Two-stroke engine, Four-stroke engine, Six-stroke engine.
– By type of ignition: Compression-ignition engine, Spark-ignition engine.
– By mechanical/thermodynamic cycle: Atkinson cycle, Miller cycle.
– Rotary engines: Wankel engine, Pistonless rotary engine.
– Continuous combustion engines: Gas turbine engine, Turbojet, Turbofan, Turboprop, Turboshaft.

**Ignition Systems and Efficiency Comparison:**
– Internal combustion engines require ignition of the mixture, either by spark ignition (SI) or compression ignition (CI).
– The most efficient reciprocating internal combustion engine in the world has a thermal efficiency over 50%.
– Ignition systems typically supply 10,000 volts.
– CD ignition can reach voltages up to 60,000 volts.
– Efficiency comparison shows that large container ships use the most efficient engines with thermal efficiency over 50%.