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Vocabulary

signify – означать, показывать

wherein – в чем, в котором

alloy – сплав

essentially – зд.: по существу

constituent – компонент, составная часть

stiffness – жесткость

fatigue life – усталостная долговечность

merely – только, просто, единственно

precise – точный

straw – солома

plywood – клееная фанера

swelling – разбухание, увеличение

fiber-reinforced – армированный волокнами

resin – смола

matrix – матрица, шаблон

Задания

  1. Выявите систему языковых средств, оформляющих техни-ческий текст.

  2. Определите, есть ли в тексте:

  • термины,

  • эквиваленты,

  • клише,

  • средства когезии,

  • прецизионная лексика.

  • Выполните письменный перевод текста на английский язык, соблюдая специфику данного жанра.

    Т е к с т 13. Flames of Gases Not Premixed

    (2.500)

    It is our aim essentially to present the processes in the ignition and combustion of explosive mixtures. In so doing, we have come upon a group of conversions in the detonation processes in which the velocity of the chemical reaction no longer plays a role. Its magnitude determines only whether detonation takes place or not. As long as we restrict ourselves to the action of premixed gases, in other words, to the action of an explosive mixture, these are the only processes independent of the reaction velocity.

    In actual practice, however, in a considerable group of combustion processes, the combustion velocity is not, determined - or at least not predominantly determined - by the reaction velocity. This is the case in the combustion of gases not premixed, examples of which are the ordinary candle flame, the illuminating-gas flame, the combustion in the outer ring of the Bunsen flame, and all technical combustions with gases not premixed. Such combustions are important either if we need a definite atmosphere above the material to be heated, e.g., a reducing atmosphere in the Siemens-Martin furnace, or if we place special value on the highest possible radiation at not too high temperatures. For this purpose, the flame of gases not premixed and with carbon elimination in the range of excess fuel is especially favorable.

    In such cases, the reaction velocity of the flame is of subordinate importance as long as the temperature of the flame is high enough. What determines the velocity of the combustion in this case is the mixing process.

    For mixing, diffusion is one of the first considerations. In technical combustion on a large scale, the conditions for mixing by diffusion alone are no longer given; for only by laminar flow could mixture exclusively by diffusion occur even at greater layer thicknesses. Under the conditions of technical combustion, however, we must generally, if not always, reckon with turbulence. Even though a discussion of these processes may lead somewhat beyond the limits of the processes treated in this book, we shall, because of the technical value of the subject, at least give a survey of the subject. We follow Rummel, who is chiefly responsible for clarifying these relations.

    Even though these processes have a special type of firing for their object, they nevertheless show especially clearly the importance of turbulent mixture, which surely can be of importance in other cases too, though it has not always been accorded sufficient attention.