Ads on the Internet - is worth a look there cars?
The Internet is full of all kinds of automotive ads. They concern mainly the sale of used cars. Is it worth it to use the online services when looking for a car? It is certainly a very good solution if you do not have stalked the offer on the eye. You have to admit, however, that the majority of websites of the car in a good condition and at a reasonable price "spread" very quickly and to hunt down the network a good car you have to try hard. On the other hand, among the announcements automotive missing SELL they offer us to buy a good car, and really the facts are quite different.
Main article: 4-stroke engine
Diagram showing the operation of a 4-stroke SI engine. Labels:
1 ? Induction
2 ? Compression
3 ? Power
4 ? Exhaust
The top dead center (TDC) of a piston is the position where it is nearest to the valves; bottom dead center (BDC) is the opposite position where it is furthest from them. A stroke is the movement of a piston from TDC to BDC or vice versa together with the associated process. While an engine is in operation the crankshaft rotates continuously at a nearly constant speed. In a 4-stroke ICE each piston experiences 2 strokes per crankshaft revolution in the following order. Starting the description at TDC, these are:78
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.