In a reciprocating air compressor the compression works per kg of air....
Compression work per kg. of air increases as clearance volume increases.
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In a reciprocating air compressor the compression works per kg of air....
Reciprocating Air Compressor and Compression per kg of Air
A reciprocating air compressor is a type of compressor that uses reciprocating motion to compress air. It has a piston that moves back and forth inside a cylinder, creating a vacuum that draws in air and then compresses it. The compression ratio is the ratio of the volume of air before compression to the volume of air after compression. The compression works per kg of air.
Effect of Clearance Volume on Compression
The clearance volume is the volume of the cylinder when the piston is at the top of its stroke. It is the volume that is not swept by the piston during compression. The clearance volume has an effect on the compression ratio and hence the compression per kg of air. The effect of clearance volume on compression is as follows:
- Increases as clearance volume increases: The compression per kg of air increases as the clearance volume increases. This is because the volume of air that is compressed is less when the clearance volume is smaller. With a larger clearance volume, the volume of air that is compressed is more, leading to a higher compression ratio and higher compression per kg of air. Hence, option 'A' is the correct answer.
- Decreases as clearance volume increases: This is the opposite of the above scenario. When the clearance volume is larger, the compression ratio decreases, leading to a lower compression per kg of air.
- Is independent of clearance volume: This scenario is not possible as the clearance volume has a direct effect on the compression ratio and hence the compression per kg of air.
- Increases with clearance volume only for multistage compressor: In a multistage compressor, the clearance volume has a different effect. The compression per kg of air increases with clearance volume only up to a certain point, beyond which it starts decreasing. This is because a larger clearance volume leads to a higher compression ratio only up to a certain point, beyond which the temperature rise during compression becomes significant and reduces the compression ratio.
Conclusion
In conclusion, the compression per kg of air in a reciprocating air compressor increases as the clearance volume increases. This is because a larger clearance volume leads to a higher compression ratio and hence higher compression per kg of air.
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