The following question consists of two statements, one labelled as the...
The air vessel in a reciprocating pump is a closed container in which the lower half is filled with fluid being pumped & the upper half filled with compressed air. Both the halves are separated by a flexible diaphragm which moves based on the pressure difference between the two fluids.
The air vessels are usually fitted near to the pump, in the discharge pipe to dampen out the pressure variations during discharge. They cannot increase the discharge in delivery pipe.
During operation, as the discharge pressure rises the air is compressed in the vessel & as the pressure falls, the air expands. The pressure energy is thus stored in the air & returned to the system when the pressure falls.
Apart from above, by using air vessels the acceleration & frictional heads are reduced. Thus the work in overcoming these losses is also reduced. This reduces the power required to drive the pump.
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The following question consists of two statements, one labelled as the...
Statement (I): An air vessel on the suction side of a reciprocating pump contributes much to an increase in efficiency.
Statement (II): Water gets sucked into the pump cylinder faster.
Explanation:
To analyze the given statements and determine the correct answer, we need to evaluate the relationship between the two statements.
Understanding Statement (I):
An air vessel on the suction side of a reciprocating pump contributes to an increase in efficiency.
Understanding Statement (II):
Water gets sucked into the pump cylinder faster.
Evaluating the statements:
To evaluate the relationship between the two statements, let's consider the function of an air vessel and its impact on pump efficiency.
Function of an air vessel:
An air vessel is a device installed on the suction side of a reciprocating pump. It consists of a chamber that contains air under pressure and is connected to the pump suction line. The main function of the air vessel is to provide a cushioning effect and reduce water hammer, which is the sudden increase in pressure caused by the rapid closure of a valve or pump stoppage.
Impact on pump efficiency:
The presence of an air vessel on the suction side of a reciprocating pump helps in maintaining a steady flow of water by absorbing the pressure fluctuations caused by the reciprocating action of the pump. It smoothens out the flow and reduces the water hammer effect. By reducing pressure fluctuations and water hammer, the air vessel contributes to higher pump efficiency.
Analysis:
From the above explanation, it is clear that both Statement (I) and Statement (II) are individually true. Statement (I) states the fact that an air vessel on the suction side of a reciprocating pump contributes to an increase in efficiency, which is supported by the explanation of its function. Statement (II) also states the fact that water gets sucked into the pump cylinder faster, which is a result of the smooth flow provided by the air vessel.
Conclusion:
Both Statement (I) and Statement (II) are individually true, and Statement (II) is the correct explanation of Statement (I). Therefore, the correct answer is option 'A'.