compression stroke उदाहरण वाक्य
उदाहरण वाक्य
- In effect, the compression stroke is two discrete cycles : the initial portion when the intake valve is open and final portion when the intake valve is closed.
- Starting at 1, the piston is at bottom dead centre and both valves are closed at the start of the compression stroke; the cylinder contains air at atmospheric pressure.
- This finds practical application in diesel engines which rely on the lack of quick heat dissipation during their compression stroke to elevate the fuel vapor temperature sufficiently to ignite it.
- Ignition occurs as the temperature of the fuel / air mixture is taken over its autoignition temperature, due to heat generated by the compression of the air during the compression stroke.
- This produces a "'homogeneous charge : "'a homogeneous mixture of air and fuel, which is ignited by a spark plug at a predetermined moment near the top of the compression stroke.
- In the case of the normally aspirated engine, at the start of the compression stroke the cylinder air / fuel volume is very high, this translates into a low starting pressure.
- The piston reaches bottom center and begins its climb up the cylinder on the compression stroke _ when the fuel / air is compressed just prior to ignition and the power stroke.
- With this design, Atkinson was able to make a more conventional engine yet preserve the efficiency of having a short compression stroke and a long expansion stroke in a rather ingenious way.
- Normally during the compression stroke, energy is used as the upward-traveling piston compresses air in the cylinder; the compressed air then acts as a compressed spring and pushes the piston back down.
- In addition, as the air is compressed and becomes heated, some of this heat is lost to the cold cylinder walls, further reducing the temperature at the top of the compression stroke.