1

МИНОБРНАУКИ РОССИИ

Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования

«Омский государственный технический университет»

MY SPECIALITY

Методические указания по английскому языку для студентов II курса Энергетического института ОмГТУ

Омск Издательство ОмГТУ

2012

2

Составители: И. И. Гейс, И. Н. Чурилова

Целью данных методических указаний является формирование у студентов

компетенции общения по теме «My speciality» на английском языке. Предназначены для студентов II курса Энергетического института ОмГТУ

(специальности Э, ЭЭ, ЭЭб) очной и дистанционной форм обучения, изуча-ющих английский язык в технических вузах.

Печатается по решению редакционно-издательского совета Омского государственного технического университета

© ОмГТУ, 2012

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16

3. Match the two parts to make correct sentences. 1) A liquid pumped onto a workpiece that is being machined, to stop it

overheating, is called a …………… . 2) The form of heat transfer that occurs with infrared heat – a form of

electromagnetic wave – is called …………… . 3) The metal fins (plates) around air-cooled engines, intended to maximize the

surface area of the hot engine that is in contact with the cooler air, are designed to act as a …………… .

4) Thick, dense, internal walls inside an energy-efficient house, which are intended to absorb neat energy during the day and store some of it to be emitted at night function as a …………… .

5) The soil and rocks on the surface of the earth remain warm at night in summer, due to the principle of …………… .

4. Circle the correct words to complete the article about condensing boilers. The first one has been done for you.

Condensing boilers are becoming increasingly popular in homes, as they use up

to 40 % less gas than traditional boilers. How do they work? By exploiting the fact that when a liquid condenses, due to the principle of latent heat of (1) fusion/vaporization, the process is (2) endothermic/exothermic. This means heat is (3) absorbed/emitted, and can thus be (4) circulated/conducted via the water inside the radiators in the home.

A condensing boiler burns natural gas (hydrocarbon fuel) to (5) heat/cool water, just like a conventional boiler. However, it achieves greater efficiency by recovering energy from water vapour. This is present in the hot, waste gas that’s produced when natural gas is burned. In a traditional boiler the (6) heat/temperature energy from the gas, which is at a (7) heat/temperature of 180 °C or more, would be (8) dissipated/radiated into the atmosphere by (9) conduction/convection, and the water vapour within it would condense in the outside air. But in a condensing boiler the hot gas passes through a (10) heat/temperature exchanger. This allows the heat from the gas to be (11) absorbed/emitted by the cool water that’s returning to the boiler after passing through the radiators in the home’s (12) cooling/heating system – heat transfer takes place from hot gas to cool water by (13) conduction/radiation through the metal of the heat exchanger. In addition, when the temperature of the gas has fallen to a certain point, the water vapour within it (14) condenses/solidifies. And it is

a radiation exchanger c heat sink e heat b coolant d thermal inertia

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18

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19

3. Now write the whole words for the unit abbreviations in the calculation

above. Look at A and В opposite to help you. The first one has been done for you.

1. m metres 4. m2 7. kg/m3 2. mm 5. m3 3. mm2 6. kg

4. Complete the extract from an article about satellite design using the words in

the box. Look at A and В opposite to help you.

cubic gravity lightweight mass square weigh weightless

Satellites need to be designed to cope with two very different phases: deployment (the journey into space by rocket) and operation (working in space).

For the first phase, engineers are faced with the problem that every (1) ………………..metre of volume taken up within the rocket will add millions of dollars to its ticket into space. And each extra gram of (2) ………………..added to the craft will increase the fuel needed to propel it upwards against the pull of (3) .............. . That extra fuel, in turn, will (4) ……….. a little more, further adding to the total weight of the craft. With the cost of kilograms so high, the satellite must therefore be as (5)………………..as possible.

In the second phase, with the orbiting satellite now (6)…………… , its mass is practically irrelevant. As for the amount of space occupied, the situation is completely reversed. The satellite’s solar panels, which transform sunlight into battery power, must unfold to cover as wide an area as possible - opening out to cover an area of several (7)………………. metres - in order to maximize their exposure to the sun.

5. Talk about different materials that are suitable for specific engineering uses

due to their density ‐ because they are either very dense, or very lightweight.

20

Unit 7

Measurable parameters

1. Read and remember the words and word‐combinations in italic.

Supply, demand and capacity

Calculating the capacity of an electricity grid – the amount of energy it needs to supply to users – might seem simple. Just add up the power supplied over a given period of time to give the total amount consumed by users. Then, divide the cumulative amount of power used during the whole period by the number of hours in the period. The result is an average level of consumption per hour. But there’s one problem with this method – and it’s a major one.

The rate of power consumption – the amount that's being consumed at a particular moment – is not constant. In other words, consumption does not stay at the same level all the time. So electricity supply requirements cannot simply be averaged out over time. People use more power at certain times of day, and less at other times, which means that demand for power fluctuates significantly.

Generally, it rises to a maximum in the evening (peak demand is at evening mealtimes), and falls to its lowest levels during the night. These fluctuations are so big that at peak times consumption can be twice as high as it is during off-peak times. Clearly, the grid needs to have sufficient capacity to meet demand when consumption peaks. But since each peak is brief, the grid will only run to capacity – at or close to its maximum capability – for a few moments each day. This means, most of the time, it has significant spare capacity.

Input, output and efficiency

Power lines and transformers are relatively inefficient, wasting energy – mainly by giving off heat.

As a result, there is a difference between input – the amount of energy put into the grid by power stations, and output – the amount used by consumers. On a typical grid, the difference between input and output is about 7 % – there is a 7 % energy loss. But if electricity is generated at the place where it’s consumed, and not transmitted through long-distance power lines, this loss can be avoided. Consequently, locally produced electricity is more efficient than grid supplied power, as there is a gain in efficiency of around 7 %.

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23

Unit 8

Material properties 1

1. Read and remember the words and word‐combinations in italic.

Tensile strength and deformation

When materials are exposed to forces, such as tension (stretching forces <——>) and compression (crushing forces —><—), they deform – that is, they change shape. The type of deformation depends on the type of force that is applied.

When a material is subjected to tension, its length will increase by a certain amount. This is called extension or elongation. It is especially important to understand the performance of materials in tension, as their tensile strength (ability to resist tension) is usually lower than their compressive strength (ability to resist compression).

Elasticity and plasticity

Some materials can extend significantly, but still return to their original shape. A material’s ability to do this is called elasticity. Rubber is an example of a very elastic material - it can be elastically deformed to a considerable extent.

If a material has very low elasticity, and is strong, engineers say it is stiff. If a material has low elasticity and is weak, it is described as brittle – that is, it fractures (breaks, due to tension) very easily. Glass is an example of a brittle material.

Some materials can change shape significantly, but do not return to their original shape. We say these materials are plastic. Often, plasticity is described in specific terms. A material that can be plastically deformed by hammering or rolling – for example, lead (Pb) – is malleable. A material that can be drawn out (stretched) into a long length – for example, copper (Cu) – is ductile.

Stages in elastic and plastic deformation

The graph below shows the typical extension behaviour of ductile materials in tensile testing – where a sample bar is subjected to a progressively increasing tensile force.

Points 0-1. The extension of the bar is proportional to the increase in tension. For example, when tension increases by 10 %, length increases by 10 %.

Point 1. The bar reaches the limit of proportionality. Beyond this point, length begins to increase at a slightly greater rate than tension.

Point 2.

Point 3.

Point 4.

Point 5.

2. Cword tw com

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24

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25

4. Complete the magazine article about springs using words from A, В and С opposite.

How are the springs used in car suspension made springy? It sounds like a silly question, but think about it for a moment. In order for a spring to compress or extend, then return to its original shape, it must be (1) ………

But springs are made from wire, and wire is made from very (2) …………… metal (often cold drawn carbon steel). When the wire is manufactured, it is not only stretched beyond its (3) ….. ….. – meaning it will no longer return to its original length – but also beyond its (4) ….. ….. , where significant, irreversible (5) ………. occurs.

The metal from which springs are made has therefore been (6) ….... deformed and, consequently, needs to have its springiness put back.

To do this, once a spring has been formed into a coil, it is tempered – a process in which it is heated and kept at a high temperature for a sustained period. This “resets” the atomic structure of the metal (partly, at least), so that after tempering, the spring will behave as it should – it can be (7) ….. deformed and will subsequently return to its original shape.

5. Think about a device, vehicle or structure you’re familiar with, and the materials used to make it. What properties do the materials have? Which properties are strengths in this situation? Which properties are weaknesses, and how are these weaknesses overcome?

Unit 9

Material properties 2

1. Read and remember the words and word‐combinations in italic.

Hardness

The hardness of a material affects its durability – that is, how long it will last. Generally, hard materials are more durable than soft materials, because they are better at resisting wear – progressively worsening damage – to their surfaces. Hardness can be defined in two main ways:

Scratch hardness describes a material’s ability to resist being scratched.

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26

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27

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28

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29

Small lengths of material, called specimens, can be stressed in a materials testing machine to measure strain and test their strength

To predict what will happen when components are loaded, engineers calculate the magnitude (size) of each load, and also work out the direction of the load – for example, vertically downwards. Load is therefore a vector quantity (or vector) – that is, a measurement with both a magnitude and a direction. This is different to a scalar quantity, which has a magnitude only.

Stress and strain

In a test, a thick cable is used to pick up a heavy object. The cable stretches slightly, but lifts the weight. A second test is done using a thinner cable – one with only half the cross-sectional area of the thick cable. This time, the cable stretches, then breaks.

Why did the thinner cable fail? Not due to a higher load, as the weight was the same. The failure was due to stress. Stress is force per unit of area and is measured in newtons per square metre, or Pascals (1 N/m2 = 1 Pa). The thinner cable was therefore stressed twice as much as the thick cable, as the same load was concentrated into a cross-sectional area that was 50 % smaller.

Why did the thick cable stretch but not break? When objects are stressed, they deform – that is, they change size (if only slightly). In the tests, the cable extended – it increased in length. Extension can be measured as a change in an object’s length compared with its original length before stress was applied. This measurement is called strain.

According to a law called Young’s Modulus of Elasticity, stress is proportional to strain. In other words, a percentage increase in stress will cause the same percentage increase in strain. However, this is only true up to a point called the limit of proportionality. If a material is overstressed – beyond this limit – it will start to become strained by a higher proportion. Stress and strain will therefore become disproportional.

2. Replace the words and expressions in italic with alternative words and expressions from A opposite.

If you look at the objects around you, it’s difficult to find something that couldn’t be smashed with a hammer. But if you laid a hammer down carefully on any of those objects, the (1) force which it (2) put on them wouldn’t be sufficient to cause even the slightest damage. This comparison illustrates the difference between:

a (3) moving force which combines mass and movement to apply (4) a shock a (5) still force, which consists only of an object’s (6) own mass.

30

Between the two situations, the (7) size of the load (8) placed on the surface is dramatically different.

The above comparison illustrates another difference in the way surfaces are (9) pressured. When a hammer is laid horizontally on a surface, its weight is spread over a relatively large area. It therefore applies a (10) spread out force. By contrast, when a hammer hits something, only the edge of the hammer head comes into contact with the surface. The force is therefore (11) focused in a small area, applying a (12) localized pressure.

3. Complete the technical checklist (1–7) based on the questions (a–g), using words from A and В opposite. The first one has been done for you.

A 1. Which components need to carry load? 2. What types of load will be carried by each part? Which loads will remain

constant, and which will differ depending on use and circumstances? 3. What amount of load will be exerted, in newtons? 4. In what directions will the loads act? 5. For the materials used, how concentrated can maximum loads be without

putting the component under too much pressure? 6. How much deformation can be expected? 7. If something breaks, will the assembly collapse dangerously, or in a

controlled, relatively safe way?

B

a. Determine which components are load-bearing. b. Analyze the types of load that will ____________ on each part. Assess _____

loads and _______________ loads. c. Calculate the _______________ of loads as ______________ quantities. d. Evaluate loads as _______________ quantities. e. Determine the maximum level of _______________ that can be carried by

materials without causing them to be _______________ . f. Calculate percentages of _______________ . g. Assess the consequences if a component _______________, determining the

potential dangers of the _______________ . 4. Think about a machine or structure you're familiar with. Give examples of

types of load which act on specific components or members. Say which components are stressed the most, and explain why.

31

БИБЛИОГРАФИЧЕСКИЙ СПИСОК

1. Bohamy David. English for technical students (Английский язык для будущих инженеров) / David Bohamy. – 2-е изд., испр. – М. : Высш. шк., 1994. – 287 с.

2. Ibbotson Mark. Cambridge English for Engineering Student’s / Mark Ibbotson. – UK : Cambridge University Press, 2008. – 111 p.

3. Ibbotson Mark. Professional English in Use. Engineering / Mark Ibbotson. – UK : Cambridge University Press, 2009. – 144 p.

4. Home Energy [Электронный ресурс] : [веб-сайт]. – URL : http://www. homeenergy.org.

5. Infinite Energy [Электронный ресурс] : [веб-сайт]. – URL : http://www. infinite-energy.com.

6. Renewable Energy World [Электронный ресурс] : [веб-сайт]. – URL : http: //www.renewableenergyworld.com.

32

ОГЛАВЛЕНИЕ

Unit 1. Current, voltage and resistance ......................................................................... 3

Unit 2. Electrical Supply ............................................................................................... 6

Unit 3. Circuits and components ................................................................................... 9

Unit 4. Energy ............................................................................................................. 12

Unit 5. Heat and temperature ...................................................................................... 14

Unit 6. Area, size and mass ......................................................................................... 17

Unit 7. Measurable parameters .................................................................................... 20

Unit 8. Material properties 1 ....................................................................................... 23

Unit 9. Material properties 2 ....................................................................................... 25

Unit 10. Load, stress and strain ................................................................................... 28

Библиографический список ...................................................................................... 31

Редактор К.В. Муковоз Компьютерная верстка О.Г. Белименко

Сводный темплан 2012 г.

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