HISTORICAL NOTES

At the beginning of the nineteenth century, the stagecoach and the saddle horse were still the means of travel on land. Freight was transported on land in wagons drawn by horses or oxen.

On water barges were also drawn by horses. The water wheel had been in-use for several centuries to drive flour mills and small manufacturing establishments. In agriculture man was still largely dependent upon his own physical strength and the work of his domestic animals. Later the steam engine was developed and applied to the operation of factories. This and the development of machine tools and machinery accelerated the industrial revolution and ultimately resulted in our modern industrial civilization which is founded upon the low-cost mass production of goods that can be sold cheaply throughout the world.

The Newcomen[22] steam engine was invented in 1705 to pump water from the English coal mines. It-was fairly well developed by 1720 and remained in extensive use for the 50 years. In 1763 a self-taught man the son of a Russian soldier Polzunov[23] worked out the project of the first universal steam engine. The construction of the engine involved great difficulties due to lack[24] of qualified assistants, lack of the necessary instruments and in general lack of help and support. Polzunov had to do almost everything with his own hands.

Polzunov's engine had been working from August to November 10, 1766 when it was stopped and put out of operation because of a leak in the boiler. But, Polzunov did not live to see the results of his work. He died in poverty on May 27, 1766.

Later on in the course of the industrial revolution in England a number of inventors designed steam engines with a view to meeting the urgent demand for these machines.

A prominent place among these early inventors belongs to James Watt[25]. James Watt, an instrument maker at the University of Glasgow, while repairing a model of a Newcomen engine, noticed the large waste of energy due to alternately heating the steam cylinder with steam and cooling it with injection water.

He realized that this loss could be reduced by keeping the cylinder as hot as possible with insulation and using a separate condenser or, water-cooled chamber which could be connected to the steam cylinder at the proper time by a valve. He patented the idea of the separate condenser in 1769. Subsequently, he closed the top of the steam cylinder with a cover or cylinder head, introduced steam alternately on both sides of the piston, and thus made the engine double acting. He invented a governor to regulate the speed of the engine, a slide valve to control the admission, expansion, and exhaust of the steam, a pump to remove the air and condensate from the condenser, and, in fact, brought the steam engine to a fairly high state of development. In 1882 Thomas Edison[26] started the Pearl Street Station[27] in New York for the purpose of supplying electricity to the users of the new incandescent lamp, thus laying the foundation for great central-station industry which now supplies the general public with electric light and power. Parsons[28] patented a reaction turbine in 1884, and in 1889 de Laval[29] was granted patents on an impulse turbine. By 1910 the steam turbine had replaced the reciprocating steam engine in the central-station industry.

During the last decade, the gas turbine in the form of the turbojet and turboprop engines has replaced the reciprocating internal combustion engine, in the military combat airplane and the faster and larger commercial aircraft. The gas turbine is also being used in such applications as electric power generation, natural gas transmission line pumping, and locomotives.

The recent development of the rocket threatens to revolutionize warfare with guided missiles and earth satellites. Since the rocket carries its own supply of oxygen for the burning of its fuel, it is capable of operating at altitudes where the earth's atmosphere is highly rarefied.


 

 


[1] ... in such a manner as to permit...—...так, чтобы позволить.

[2] in effect — в сущности

[3] until after combustion is reasonably complete — до тех пор, пока сжигание не завершено

[4] if combustion is to be complete in a furnace of economical size когда должна быть обеспечена полнота сжигания в топках экономичных размеров

[5] to force a shutdown (of the unit) — вызвать остановку (агрегата)

[6] U-shaped paths — U-образные траектории (пути, формы)

[7] in areas served by natural-gas transmission lines —в областях, через которые проходят магистральные газопроводы природного газа

[8] coal- or oil-fired units — агрегаты, использующие угольное или жидкое топливо

[9] making it possible to burn — давая возможность сжигать

[10] in liquids and gases'at rest — в жидкостях и газах, находя­щихся в состоянии покоя

[11] parallel circuits of 2-in. o.d. tubes — параллельные линии из двухдюймовых труб

[12] a typical stoker-fired steam-generating unit in the smaller size range — типичный парогенератор с механической топкой из серив малых агрегатов

 

[13] has at his disposal — имеет в своем распоряжении

 

[14] H. P. cylinder=high pressure cylinder цилиндр высокого давления

 

[15] are less apt to occur реже встречаются

[16] at right angles под прямым углом

[17] volume rate of flow — объемный расход

[18] volume capacity — объемная производительность

[19] will be whatever is necessary — будет соответствовать необ­ходимости

[20] when capable of handling gases — если они могут работать c газами

 

[21] as heat — в виде тепла

 

[22] Newcomen—Ньюкомен, Томас (1663—1729), английский изобретатель

[23] Polzunov — Ползунов Иван Иванович (1728—1766), выдающийся русский теплотехник, один из изобретателей универсального теплового двигателя

[24] due to lack — из-за недостатка

[25] James Watt — Уатт, Джемс (1736—1819), выдающийся английский изобретатель

[26] Thomas Edison — Эдисон, Томас Алва (1847-1931), выдающийся американский электротехник, изобретатель, основатель крупных электротехнических предприятий и компаний

[27] Pearl Street Station — электростанция на Перл Стрит

[28] Parsons — Парсонс, Чарлз Алджернон (1854—1931), английский инженер и предприниматель, изобретатель паровой реактивной турбины

[29] de-Laval — Лаваль, Карл Густав Патрик де (1845—1913), шведский инженер и изобретатель








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