Five-stroke engine is currently a concept

engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ...

invented by Gerhard Schmitz in 2000. Schmitz's concept is being developed by Ilmor Engineering. Ilmor's prototype is an

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 co ...

that uses a solid

cylinder block In an internal combustion engine, the engine block is the structure which contains the cylinders and other components. In an early automotive engine, the engine block consisted of just the cylinder block, to which a separate crankcase was attac ...

with

electric motor An electric motor is an electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a wire winding to generate forc ...

s driving the

oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturate ...

and

water cooling Cooling tower and water discharge of a nuclear power plant Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and non ...

pump A pump is a device that moves fluids ( liquids or gases), or sometimes slurries, by mechanical action, typically converted from electrical energy into hydraulic energy. Pumps can be classified into three major groups according to the method the ...

s. The prototype uses two

overhead camshaft An overhead camshaft (OHC) engine is a piston engine where the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combustion ...

s with standard

poppet valve A poppet valve (also called mushroom valve) is a valve typically used to control the timing and quantity of gas or vapor flow into an engine. It consists of a hole or open-ended chamber, usually round or oval in cross-section, and a plug, usual ...

s. The five-stroke prototype engine is

turbocharged In an internal combustion engine, a turbocharger (often called a turbo) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake gas, forcing more air into the engine in order to pro ...

. The goal of the five-stroke engine is to have higher efficiency with lower fuel use. To increase efficiency a secondary cylinder is added as an expansion processor to extract more energy from the fuel. Gerhard Schmitz's concept engine uses two high pressure (HP) fired cylinders with standard

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 directio ...

power cycles. The

exhaust gas Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline (petrol), diesel fuel, fuel oil, biodiesel blends, or coal. According to the type of engine, it is discharged into the atmosphere through a ...

from the two HP work cylinders is fed into a one larger central low pressure (LP) expansion cylinder. The hot exhaust is used to produce more power. The low pressure expansion cylinder is adjustable to maintain the best expansion ratio, regardless of the

compression ratio The compression ratio is the ratio between the volume of the cylinder and combustion chamber in an internal combustion engine at their maximum and minimum values. A fundamental specification for such engines, it is measured two ways: the stat ...

. Prototype has produced very good fuel consumption over a standard gas engine, by about 10%.Ilmor 5 Stroke Engine – 700cc Turbo 3 Cylinder – 130 bhp, Better Mileage, Less Weight, By Paul Crowe
/ref> Concept of 'Double expansion' was common and successful in Ship Steam Machines, Titanic had one of it.

Nicolaus Otto Nicolaus August Otto (10 June 1832, Holzhausen an der Haide, Nassau – 26 January 1891, Cologne) was a German engineer who successfully developed the compressed charge internal combustion engine which ran on petroleum gas and led to the mod ...

built in 1879 a 5-stroke engine with same arrangement as Ilmor, but customers returned it due to poor performance. ('The romance of engines', T Suzuki, SAE, pp 87-93). Two Spanish patents, ES0156621, F Jimeno-Cataneo, 1942; and ES0433850, C Ubierna-Laciana, 1975; describe 5-Stroke engines identical to that of Gerhard Schmitz, this engine had a fellowship to Burgundy University to be studied. JW Eisenhuth patented, US640890, 1900, an 'Air and gas engine', with double expansion. A car with this engine was in exhibition in Harrah collection, fate of car after the collection was dismantled is unknown.

Applications

Planned motorcycle design from Ilmor Engineering 1,478 cc totally 3 cylinder (HP and LP cylinders) uses a five-stroke engine.

Advantages

* For a gasoline engine, the engine has an expansion ratio near that of

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 a so-ca ...

, about 14.5:1. * Adjustable compression. * Higher

mean effective pressure The mean effective pressure (MEP) is a quantity relating to the operation of a reciprocating engine and is a measure of an engine's capacity to do work that is independent of engine displacement.Heywood, J. B., "Internal Combustion Engine Fundam ...

with less fuel, due to expansion cylinder. * Use standard engine parts, no special one of a kind parts. * In theory, additional water injection can be used for cooling the cylinder walls. It leads to quick steam expansion and can increase the efficiency of the expansion cylinder.

Disadvantages

* Increased costs due unique design. Not yet mass-produced. * Two different cylinder sizes. * More complex than 2 cylinder engine.

Specification

* Current prototype is for

motorcycle A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruisin ...

use. * 3 cylinder (two high pressure and one low pressure) * 700 cc 2 HP cylinder * 1478 cc total 3 cylinders (HP and LP) * 130

horsepower Horsepower (hp) is a unit of measurement of power, or the rate at which work is done, usually in reference to the output of engines or motors. There are many different standards and types of horsepower. Two common definitions used today are th ...

@ 7000rpm * 166 Nm @ 5000rpm * 226g/kWh BSFC

References

External links