Newton's Third Law and Reaction Steam Turbines

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In an impulse steam turbine, what produces the force to rotate the blades?

Steam velocity acting on the blades (correct)

Expansion of the steam

Increase in pressure of the steam

Change in momentum of the blades

What causes the steam to expand and increase in velocity in a steam turbine?

First-stage nozzle (correct)

Shaft glands

Revolving blades

Throttle valve

What is used to reverse the flow of steam between each pair of revolving blades in a steam turbine?

Steam seals

Thrust bearings

Labyrinth packing seals

Stator blades (correct)

What part of an impulse steam turbine prevents the higher pressure of one stage from leaking through to the next stage?

Labyrinth packing seals (C) Signup and view all the answers

What part is used in large impulse steam turbines to maintain a constant speed?

Hydraulic governors (C) Signup and view all the answers

What type of bearings maintain the vertical position of the rotor in an impulse steam turbine?

Radial (main) or journal bearings/sleeve bearings (D) Signup and view all the answers

What occurs if radial or thrust bearings exceed the specified tolerance in an impulse steam turbine?

Overheating and distortion (D) Signup and view all the answers

What do reaction turbines develop torque by reacting to?

Pressure of the gas or fluid (B) Signup and view all the answers

What is the primary function of a steam turbine?

To convert heat energy in steam to kinetic energy (B) Signup and view all the answers

Which of the following are the three types of steam turbines commonly used?

Impulse, Reaction, and Special-purpose (D) Signup and view all the answers

What is the primary function of impulse turbines?

To change the direction of flow of a high velocity fluid or gas jet (B) Signup and view all the answers

What is the working principle of an impulse steam turbine?

The steam passes through fixed nozzles into the turbine and the relative velocity of steam at the outlet of the moving blades is the same as the inlet to the blades (C) Signup and view all the answers

What determines the amount of work performed by steam turbines?

The temperature and pressure of the steam (A) Signup and view all the answers

Which type of steam turbines are designed for specific plant requirements?

Special-purpose turbines (A) Signup and view all the answers

What happens to the pressure of steam during expansion in an impulse steam turbine?

The pressure decreases (D) Signup and view all the answers

In a reaction steam turbine, what causes the backward movement of the arms?

The forward force of the water (C) Signup and view all the answers

What is the function of fixed blades in a reaction steam turbine?

To act as nozzles for the steam (B) Signup and view all the answers

How does the velocity of steam change in the nozzle-shaped passages of a reaction steam turbine?

It increases (B) Signup and view all the answers

What causes a reactive force on the revolving blades in a reaction steam turbine?

Steam striking the fixed blades (C) Signup and view all the answers

What distinguishes a reaction steam turbine from an impulse steam turbine in terms of admission of steam?

Full admission of steam all around the wheel (C) Signup and view all the answers

What physical characteristic results from the difference in pressure between stages in a reaction steam turbine?

'Large axial thrust' (A) Signup and view all the answers

What part of a reaction steam turbine serves the same function as in an impulse steam turbine?

'Throttle and governor system' (B) Signup and view all the answers

What is used in a reaction steam turbine to reduce leakage between stages and warn of excessive radial tolerance?

'Sealing strips' (A) Signup and view all the answers

What is the thermal efficiency of the steam turbine in problem 1?

32.94% (C) Signup and view all the answers

What is the total thermal efficiency of the power plant in problem 1?

22.10% (D) Signup and view all the answers

In problem 2, what is the thermal efficiency of the gas turbine plant?

33.3% (B) Signup and view all the answers

What is the electric efficiency of the gas turbine plant in problem 2?

90% (D) Signup and view all the answers

What is the value in dollars of the energy wasted in one day in the Chimney considering the price of each kW.Hr is $0.11 for the first scenario?

$18,784.65 (A) Signup and view all the answers

What is the power (in kW) wasted in the condenser for the first scenario?

7115.4 kW (A) Signup and view all the answers

What is the percentage of power wasted in respect to the input power for the first scenario?

77.9% (A) Signup and view all the answers

What is the power input (in kW) to the boiler considering boiler thermal efficiency of 85% for the first scenario?

11,312.2 kW (A) Signup and view all the answers

In a reaction steam turbine, what is the purpose of the balance piston or dummy piston?

To balance all thrust at full load on the machine and compensate for inequalities of thrust at other loads (C) Signup and view all the answers

What is the main cause of steam leakage around the tops of the revolving blades and under the bottoms of the fixed blades in a reaction steam turbine?

High pressure on each side of every row of blades (C) Signup and view all the answers

Which process in the ideal Rankine cycle involves adiabatic reversible expansion through the turbine?

1-2 or 1'-2' (B) Signup and view all the answers

What does the section 4-B represent in the steam generator of an ideal Rankine cycle?

Bringing the subcooled liquid to saturated liquid at B (C) Signup and view all the answers

What does the thermal efficiency of a turbine represent?

The ratio of heat energy used in the turbine to the heat energy available in the steam (A) Signup and view all the answers

What is electric efficiency in a turbine system defined as?

The ratio of electrical energy output to the heat energy input (A) Signup and view all the answers

In a Rankine cycle power plant, what is the value of dollar energy wasted in one day in the condenser, considering the price of each kW.Hr is $0.11?

$0.11 * Power wasted in kW (D) Signup and view all the answers

In a gas turbine power plant running on natural gas, how is thermal efficiency calculated?

(Mechanical power available for producing electric power / Heat addition by burning fuel) * 100% (C) Signup and view all the answers