Historical design Dugald Clerk developed the first two cycle engine in 1879.It used a separate cylinder which functioned as a pump in order to transfer the fuel mixture to the cylinder.6 In 1899 John Day simplified Clerk's design into the type of 2 cycle engine that is very widely used today.13 Day cycle engines are crankcase scavenged and port timed. The crankcase and the part of the cylinder below the exhaust port is used as a pump.
On the downstroke the piston now compresses the fuel mix, which has lubricated the piston in the cylinder and the bearings due to the fuel mix having oil added to it.As the piston moves downward is first uncovers the exhaust, but on the first stroke there is no burnt fuel to exhaust.
When the piston rose close to TDC a spark ignites the fuel.
As the piston is driven downward with power it first uncovers the exhaust port where the burned fuel is expelled under high pressure and then the intake port where the process has been completed and will keep repeating. Later engines used a type of porting devised by the Deutz company to improve performance.
Blower scavenged Diagram of uniflow scavenging Using a separate blower avoids many of the shortcomings of crankcase scavenging, at the expense of increased complexity which means a higher cost and an increase in maintenance requirement.An engine of this type uses ports or valves for intake and valves for exhaust, except opposed piston engines, which may also use ports for exhaust. The blower is usually of the Roots-type but other types have been used too.
This design is commonplace in CI engines, and has been occasionally used in SI engines. CI engines that use a blower typically use uniflow scavenging.
In this design the cylinder wall contains several intake ports placed uniformly spaced along the circumference just above the position that the piston crown reaches when at BDC.
An exhaust valve or several like that of 4-stroke engines is used.The final part of the intake manifold is an air sleeve which feeds the intake ports. The intake ports are placed at an horizontal angle to the cylinder wall (I.e: they are in plane of the piston crown) to give a swirl to the incoming charge to improve combustion.
The most powerful of them have a brake power of around 4.5 MW or 6,000 HP.
The comparable class GE AC6000CW whose prime mover has almost the same brake power uses a 4-stroke engine. An example of this type of engine is the Wärtsilä-Sulzer RTA96-C turbocharged 2-stroke Diesel, used in large container ships.It is the most efficient and powerful internal combustion engine in the world with a thermal efficiency over 50%.9101112 For comparison, the most efficient small four-stroke engines are around 43% thermally-efficient (SAE 900648);citation needed size is an advantage for efficiency due to the increase in the ratio of volume to surface area. See the external links for a in-cylinder combustion video in a 2-stroke, optically accessible motorcycle engine.Źródło: https://en.wikipedia.org/wiki/Internal_combustion_engine
For many people, the same drive various means of transport is a very nice feeling.Moreover, the use of buses or cars is sometimes necessary.
Carrying heavy goods they are most often carried out also by means of heavy equipment moving on the roads..