Паровой двигатель.

STEAM ENGINE.

Exercise 1. Read and memorize the following words and word combinations.

steam – пар; force – сила; piston – поршень; connecting rod – шатун; flywheel – маховик; rotational force – сила вращения; external combustion engine – двигатель внешнего сгорания; boiler – котёл; pump – насос; pump out – выкачивать; coal mine – шахта; transmit – передавать; to power – приводить в действие, freight trains – грузовой поезд; replace – заменять; sail – парус; output – мощность; cost – стоимость; operate - работать; power generation – производство электроэнергии; efficiency – КПД

Exercise 2. Match the word combinations.

Exercise 3. Read and translate the text.

A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The principle of the steam engine is simple. When water is boiled, it changes into steam. The more the steam is heated, the more pressure it has.

The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force is transformed, by a connecting rod and a flywheel, into rotational force for work.

A steam ploughing engine (паровой плуг) by Kemna

The first commercially successful engine that could transmit continuous power to a machine was developed in 1712 by Thomas Newcomen¹. It was used to pump out the water from coal mines. James Watt made a critical improvement by removing spent steam to a separate vessel (в отдельную емкость) for condensation, greatly improving the amount of work obtained per unit of fuel consumed (значительно увеличив количество работы, получаемой на единицу потребляемого топлива).

By the 19th century, stationary steam engines powered the factories of the Industrial Revolution. Steam engines replaced sail for ships, and steam locomotives operated on the railways.

A marine steam engine on the 1907 oceangoing tug Hercules

 In 1825 George Stephenson built the Locomotion for the Stockton and Darlington Railway. This was the first public steam railway in the world. The Liverpool and Manchester Railway opened in 1830 making exclusive use of steam power for both passenger and freight trains.

The final major evolution of the steam engine design was the use of steam turbines starting in the late part of the 19th century. Steam turbines are generally more efficient than reciprocating piston type steam engines (for outputs above several hundred horsepower), have fewer moving parts, and provide rotary power directly instead of through a connecting rod system or similar means. Steam turbines virtually replaced reciprocating engines in electricity generating stations early in the 20th century, where their efficiency, higher speed appropriate to generator service, and smooth rotation were advantages.

Reciprocating piston type steam engines were the dominant source of power until the early 20th century. Then electric motors and internal combustion engines gradually replaced reciprocating (piston) steam engines in commercial usage. Steam turbines replaced reciprocating engines in power generation, due to lower cost, higher operating speed, and higher efficiency.

Exercise 4. Answer the following questions:

1. What is the principal of the steam engine?

2. How is the pushing force transformed into rotational force?

3. How was a steam engine used in coal mines?

4. How did James Watt improve the engine?

5. When and where was the first public steam railway operate?

6. What is the final major evolution of the steam engine?

7. Why did steam turbines replace reciprocating engines in power generation?

¹Паровая машина Ньюкомена — пароатмосферная машина, которая использовалась для откачки воды в шахтах и получила широкое распространение в XVIII веке.

https://en.wikipedia.org/wiki/Steam_engine