Gift for car lovers
Buying a gift can be a problem, especially if we want to make a gift without obligation, but still quite meaty and really interesting for the recipient. What buy a fan of the automotive industry? Certainly a nice gift idea for such a person is choosing a book in this field. However, one should check if the person you want to give away no longer has such a home. Available on the market, however, is much different proposals in this regard, that will certainly find something suitable, as well as inexpensive. The book is a very good gift idea for people of all ages, and entered at the start of commemorative dedication certainly will constitute a kind of souvenir. So let's decide on the choice of books, if you are looking for an idea for a gift for a fan of the automotive industry.
Main article: Diesel cycle
P-v Diagram for the Ideal Diesel cycle. The cycle follows the numbers 1?4 in clockwise direction.
Most truck and automotive diesel engines use a cycle reminiscent of a four-stroke cycle, but with a compression heating ignition system, rather than needing a separate ignition system. This variation is called the diesel cycle. In the diesel cycle, diesel fuel is injected directly into the cylinder so that combustion occurs at constant pressure, as the piston moves.
Otto cycle: Otto cycle is the typical cycle for most of the cars internal combustion engines, that work using gasoline as a fuel. Otto cycle is exactly the same one that was described for the four-stroke engine. It consists of the same four major steps: Intake, compression, ignition and exhaust.
PV diagram for Otto cycle On the PV-diagram, 1?2: Intake: suction stroke 2?3: Isentropic Compression stroke 3?4: Heat addition stroke 4?5: Exhaust stroke (Isentropic expansion) 5?2: Heat rejection The distance between points 1?2 is the stroke of the engine. By dividing V2/V1, we get: r, where r is called the compression ratio of the engine.
Using a separate blower
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 largest reciprocating IC are low speed CI engines of this type; they are used for marine propulsion (see marine diesel engine) or electric power generation and achieve the highest thermal efficiencies among internal combustion engines of any kind. Some Diesel-electric locomotive engines operate on the 2-stroke cycle. The most powerful of them have a brake power of around 4.5 MW or 6,000 HP. The EMD SD90MAC class of locomotives use a 2-stroke engine. 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 WÃ¤rtsilÃ¤-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.