What are Hydraulic Machines?

The machines which convert hydraulic energy produced by the water into mechanical energy are known as hydraulic machines. These machines are hugely responsible for the production of electrical energy using a water resource.

Turbines are the hydraulic machines which transform hydraulic energy into mechanical energy; on the other hand, pumps are the hydraulic machines which transform the mechanical energy into hydraulic energy.

Fluid power is used by hydraulic machinery for their functioning. A large amount of power is transmitted in these machinery through small tubes and hoses. In these types of machinery, the fluid is transferred to motors and hydraulic cylinders throughout the machine, where it gets pressurised and further transferred through tubes and control valves.

The generation of hydroelectric power in today’s world is the cheapest as compared to the other power generating sources such as nuclear energy, coal, petroleum etc.

Uses of Hydraulic Machines

• To move machines and equipment that fulfil several tasks, hydraulics is extensively used in practically every industry. For example, cranes, tractors, hydraulic braking systems etc.
• For power movement, hydraulic fluid pressure is used by hydraulic machines.
• Dump trucks, cranes, jackhammers, aluminium or plastic extruders etc., are also examples of hydraulic machines.
• Almost every vehicle on the road is equipped with a hydraulic system in the form of hydraulic brakes or brake fluid which is an important component of a vehicle’s braking system.

Important Questions on Hydraulic Machines

1) There are _____ types of reaction turbines.

a) 5

b) 7

c) 6

d) 8

Correct Option: (a)

Explanation: There are generally 5 types of reaction turbines, they are: VLH, Gorlov helical turbine, Francis, Kaplan and Tyson turbine.

2) Inlet energy in hydraulic turbines is greater than the outlet energy. Is it true or false?

a) True

b) False

Correct Option: (a)

Explanation: The above statement is true because the functioning member which collects energy at the inlet should be more as compared to energy at the outlet.

3) Which among the following principles is applicable in hydraulic turbines?

a) Bragg’s law

b) Newton’s second law

c) First law of thermodynamics

d) None of these

Correct Option: (b)

Explanation: The principle of momentum that comes under Newton’s second law is used in hydraulic machines.

4) What is the function of buckets and blades used in a turbine?

a) Change the direction of the water

b) To switch off the turbine

c) Regulate the speed of the wind

d) None of these

Correct Option: (a)

Explanation: To change the direction of water, blades and buckets are used in a turbine. These blades and buckets also change the momentum of the water. And therefore, due to the change in momentum, a force is generated to rotate the shaft of a hydraulic machine.

5) The electric power obtained from the energy of the water is termed _____.

a) Nuclear power

b) Rotor power

c) Thermal power

d) Hydroelectric power

Correct Option: (d)

Explanation: Hydropower is the energy obtained from the energy of water, and therefore, the electric power obtained is termed hydroelectric power.

6) If a turbine is used to run an electric power generator connected to the turbine shaft, then which energy is used by it to generate electricity?

a) Mechanical Energy

b) Rotational Energy

c) Electric Energy

d) Potential Energy

Correct Option: (a)

Explanation: The kinetic and potential energies are the major energies that are produced in a turbine, which are eventually converted to some useful mechanical energy.

7) Hydraulic Machines fall under the category of _____.

a) Capacitors

b) Kinetic machinery

c) Compressors

d) Roto-dynamic machinery

Correct Option: (d)

Explanation: Since the principle of rotation of blades is used by hydraulic machines to alter the speed of the water, they fall under the category of roto-dynamic machinery.

8) Which among the following types of turbines fluctuates the pressure of the water entered through it?

a) Reaction turbines

b) Kinetic turbines

c) Impulse turbines

d) Axial flow turbines

Correct Option: (a)

Explanation: Reaction turbines are used to change the pressure of the water through its motion.

9) Which type of turbine is used to change the velocity of the water through its flow?

a) Potential turbines

b) Kinetic turbines

c) Impulse turbines

d) Axial flow turbines

Correct Option: (c)

Explanation: Impulse turbines are used in the process of changing the velocity of the water to convert potential energy into kinetic energy.

10) Which among the following types of the turbine is a Francis Turbine?

a) Screw Turbine

b) Impulse Turbine

c) Reaction turbine

d) Turbo turbine

Correct Option: (c)

Explanation: Francis turbine is a reaction turbine because it works on the changing pressure of fluid and the reaction provided by the fluid flow.

Practice Questions

1) What is Pascal’s law?

2) What is Bernoulli’s principle?

3) What are hydraulic turbines?

4) Write some applications of Pascal’s law.

5) Define specific volume.

Suggested Videos

Stay tuned to BYJU’S and Fall in Love with Learning!