What type of energy is primarily used in hydraulic systems?
A Kinetic and pressure energy
B Electrical energy
C Thermal energy
D Nuclear energy
Hydraulic systems work by converting mechanical energy into fluid energy, utilizing both kinetic and pressure energy. This energy is then transmitted through a fluid medium to perform work in various applications.
What is the main function of a draft tube in a hydraulic turbine?
A Increase velocity
B Store water
C Convert kinetic energy to pressure energy
D Reduce flow rate
A draft tube helps in energy recovery by converting the remaining kinetic energy of water leaving the turbine into pressure energy, thereby improving overall efficiency and reducing exit losses.
Which pump is most suitable for high-viscosity fluids?
A Centrifugal pump
B Gear pump
C Reciprocating pump
D Jet pump
Gear pumps are positive displacement pumps that can handle high-viscosity fluids efficiently. They provide a constant flow rate and work well for thick oils, lubricants, and viscous liquids.
What happens to the velocity of water in a nozzle?
A Decreases
B Remains constant
C Drops to zero
D Increases
A nozzle constricts the flow area, increasing the velocity of water as per the principle of conservation of energy (Bernoulli’s theorem). This is commonly used in jet turbines and fluid propulsion.
What is the purpose of a surge chamber in a pipeline system?
A Store excess water
B Reduce pressure variations
C Increase water velocity
D Prevent cavitation
A surge chamber helps to absorb sudden pressure changes in pipelines, reducing the risk of water hammer. This ensures smooth operation in hydropower plants and long-distance water transmission systems.
What does a hydraulic ram pump do?
A Measures fluid velocity
B Stores hydraulic energy
C Increases water pressure
D Pumps water without electricity
A hydraulic ram pump operates using the energy of flowing water. It uses a cyclic process of pressure surges to lift a portion of water to a higher elevation without requiring an external power source.
What is the function of wicket gates in a Francis turbine?
A Regulate water flow
B Increase turbine speed
C Reduce cavitation
D Store hydraulic energy
Wicket gates are adjustable vanes that control the amount of water entering a Francis turbine. They help in maintaining efficient power output and prevent excessive wear on turbine components.
In an impulse turbine, where does most of the energy conversion occur?
A Runner
B Nozzle
C Draft tube
D Guide vanes
In an impulse turbine, the nozzle converts the water’s pressure energy into high-velocity jets. This jet strikes the turbine blades, causing them to rotate and generate mechanical energy.
What does cavitation in a turbine cause?
A Increases efficiency
B Improves energy conversion
C Reduces performance and damages blades
D Increases water pressure
Cavitation occurs when water pressure drops below vapor pressure, forming vapor bubbles. When these bubbles collapse, they create intense shock waves, leading to erosion of turbine blades and efficiency loss.
What is the purpose of a flow control valve?
A Control flow rate
B Store hydraulic energy
C Measure fluid temperature
D Increase water pressure
A flow control valve regulates the rate of fluid flow in a hydraulic system. It ensures that the system operates within its design parameters, preventing excessive pressure or energy loss.
What type of turbine is used in a pumped-storage hydropower plant?
A Francis turbine
B Reversible pump-turbine
C Kaplan turbine
D Pelton wheel
A reversible pump-turbine functions as a turbine during power generation and as a pump during off-peak hours to store water in an upper reservoir, allowing efficient energy management.
What is the main purpose of an expansion joint in a pipeline?
A Absorb thermal expansion and contraction
B Increase flow rate
C Reduce turbulence
D Store excess water
Expansion joints allow for the thermal expansion and contraction of pipelines due to temperature changes. They prevent excessive stress on pipes, reducing the risk of cracks or failure.
What happens to pressure in a venturi meter’s throat section?
A Increases
B Remains constant
C Decreases
D Drops to zero
In a venturi meter, as fluid velocity increases in the throat section, the pressure decreases according to Bernoulli’s principle. This pressure difference is used to measure flow rate.
What is the primary function of a hydraulic clutch?
A Transmit power smoothly
B Store hydraulic energy
C Measure fluid velocity
D Increase engine speed
A hydraulic clutch uses fluid coupling to transfer power between the engine and transmission. It provides smooth engagement, reducing mechanical wear and preventing sudden jerks during power transmission.
What does a spillway do in a dam?
A Release surplus water safely
B Store excess water
C Generate power
D Control dam height
A spillway is a safety feature in dams that allows controlled discharge of excess water to prevent overflow and structural damage. It helps maintain a safe reservoir water level during floods.