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aero&astro
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I know the cut off ratio is of the specific volumes, but is that it? And what exactly do they tell you
student23 said:Is it possible to explain it much simpler please? ( I am very weak in physics.)
So basically,
What I know so far is (in simple steps)
1) In a box, air is compressed.
2) Fuel is added
so
3) ignites
4) and produce work
if compression ratio goes up, efficiency increases. But why? because we can put more Air in the box ? I am sorry I am totally confused.
The compression ratio is the ratio of the volume of the combustion chamber at its largest capacity (when the piston is at the bottom of its stroke) to the volume at its smallest capacity (when the piston is at the top of its stroke).
The compression ratio is a measure of the maximum amount of compression that occurs in the combustion chamber, while the cut off ratio is a measure of the minimum amount of compression that is necessary for the engine to run efficiently.
The compression ratio directly affects the power, efficiency, and emissions of an engine. A higher compression ratio can result in more power and better fuel efficiency, but it also increases the risk of engine knock. Therefore, it is important to find the optimal compression ratio for a specific engine.
Compression ratio is calculated by dividing the volume of the combustion chamber at its largest capacity by the volume at its smallest capacity. This can be measured directly or calculated using the cylinder bore, stroke length, and piston displacement.
Yes, the compression ratio can be changed by making modifications to the engine, such as changing the size of the combustion chamber or altering the piston stroke. However, this should only be done by experienced professionals to ensure the engine's performance and reliability.