Correct Answer - Option 4 : Pump
Explanation:
Pumps
- The hydraulic machines which convert the mechanical energy into hydraulic energy are called pumps.
- If the mechanical energy is converted into pressure energy by means of the centrifugal force acting on the fluid, the hydraulic machine is called a centrifugal pump.
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Centrifugal pumps
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Reciprocating pumps
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The discharge is continuous and smooth
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The discharge is fluctuating and pulsating
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It can handle a large quantity of liquid with low pressure
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It handles a small quantity of liquid only with high pressure
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It can be used for lifting highly viscous liquids
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It is used only for lifting pure or less viscous liquids
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It is used for large discharge through smaller heads
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It is meant for a small discharge and high heads
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The cost of a centrifugal pump is less as compared to a reciprocating pump
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The cost of a reciprocating pump is approximately four times the cost of a centrifugal pump
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The Centrifugal pump runs at high speed. They can be coupled to an electric motor
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It runs at a low speed. Speed is limited due to consideration of separation and cavitation
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The operation of a centrifugal pump is smooth and without much noise. The maintenance cost is low
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The operation of a reciprocating pump is complicated and with much noise. The maintenance cost is high.
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It requires a smaller floor area and the installation cost is low
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It requires a larger floor area and installation cost is high
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Efficiency is high
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Efficiency is low
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Hydraulic turbines:
Hydraulic turbines may be considered as hydraulic motors or prime movers of a water–power development, which convert water energy (hydropower) into mechanical energy (shaft power).
The shaft power developed is used in running electricity generators directly coupled to the shaft of the turbine, thus producing electrical power.
The hydraulic turbine is a rotary machine actuated by the impulse and/or reaction of a water current attacking the rotor (called the runner), which consists of a series of buckets or curved vanes or blades.
Classification of turbines on the basis of energy at inlet:
1. Impulse turbine:
This has only kinetic energy at the inlet.
E.g- Pelton wheel.
2. Reaction turbine:
This has kinetic energy and pressure energy both at the inlet.
E.g- Francis turbine, Propeller turbine, Kaplan turbine, Thomson turbine
Nozzle: It is a pipe or tube of varying cross-sections. It is generally used to control the pressure or rate of flow.
Boiler: It is a closed vessel in which steam is produced from water by the combustion of fuel.
