Передмова (стр. 33 )

Exercise 36. Say whether the given statements are true or false. If a statement is wrong, correct it. If true, enrich it with details.

1. Gas turbine engines are of very high power-to-weight ratio. 2. Reciprocating engines are smaller than gas turbine engines of the same power rating. 3. Gas turbine engines are of simpler design than reciprocating engines. 4. One of the main disadvantage of the gas turbine engine is its high operation speeds. 5. High operating pressure is the advantage of gas turbine engines. 6. Gas turbine engines need very high-performance, strong and heat-resistant materials, so they are high in cost. 7. Gas turbine engines disadvantage is that they use more fuel, as compared to reciprocating engines and they are not so good unless in continual operation.

Exercise 37. Work in plete the following questions on texts 3, 4 and answer them.

… is a gas turbine?

… does a gas turbine have?

… is energy released?

… does a gas turbine operate?

… does higher combustion temperature mean greater efficiency?

… are combined cycle designs used for hot water production?

… is the difference in simple and more sophisticated designs?

… are jet engines optimized for?

… do jet engines produce thrust?

… are auxiliary power units designed for?

… can industrial gas turbines be efficient?

… can industrial gas turbines be used?

… are the advantages of simple cycle gas turbines?

… of industrial gas turbines is more efficient?

… are turboshaft engines used?

… are radial gas turbines applications?

… are the main distinctive features of radial gas turbines design?

… are the main advantages of gas turbine engines?

Exercise 38. Speak on:

1.  Types of Turbines.

2.  Turbines Operation and Purposes.

3.  Gas Turbines Design and Operation.

4.  Industrial Gas Turbines.

Exercise 39. Choose the right answers to the questions on texts 3 and 4.

1. What is a turbine used for?

a) for compression of gas;

b) for refinery of gas;

c) for extraction of energy from a fluid flow.

2. What turbines require a pressure casement?

a) impulse turbines;

b) reaction turbines;

c) wind turbines.

3. What types of turbines are used in power plants using coal, fuel oil or nuclear power?

a) water turbines;

b) wind turbines;

c) steam turbines.

4. What turbines are referred to internal combustion machines?

a) wind turbines;

b) water turbines;

c) gas turbines.

5. How are turbines with a shroud at rotor blade tips called?

a) shroudless turbines;

b) bladeless turbines;

c) shrouded turbines.

6. What influences the efficiency of all cyclic heat engines?

a) more complex construction;

b) higher combustion temperature;

c) larger size of engine.

7. What does rotor tip speed depend on?

a) combustion temperature;

b) engine design;

c) engine size.

8. What engines produce thrust primarily from the direct impulse of exhaust gases?

a) turbofans;

b) turboshaft engines;

c) turbojets.

9. What industrial gas turbines are used to supply power during peak demand?

a) combined cycle gas turbines;

b) simple cycle gas turbines;

c) large industrial gas turbines.

10. What are the disadvantages of gas turbine engines?

a) low operating pressure;

b) simple design;

c) high fuel consumption.

UNIT VIII. Environmental Protection

Exercise 1. Memorize the following words and word combinations to text 1.

Environment – навколишнє середовище

maintain – зберігати

exhale – видихати

fossil fuel – викопне пальне

release – вивільняти, видаляти

content – вміст

ash – попіл, зола

virtually – фактично, реально, насправді; по суті

pollutant – забруднююча речовина

emit – виділяти, випромінювати; випускати

emission – виділення, викид (тепла, тощо); емісія

mitigate – зменшувати, послабляти; пом’якшувати, полегшувати

issue – проблема, питання

translate – перетворювати(ся)

disastrous – згубний

panel – комісія

Intergovernmental Panel on Climate Change (IPCC) – міжурядова комісія зі змін клімату

Fahrenheit – за Фаренгейтом

chlorofluorocarbon – хлорофторний вуглець

trap – утримувати

potent – сильнодійний

leak – витiк

research – досліджувати

offset – компенсувати

waste management - нераціональне / неефективне управління

Exercise 2. Read and translate text 1.

Text 1. Environmental Benefits of Natural gas

Natural gas is an extremely important source of energy for reducing pollution and maintaining a clean and healthy environment. In addition being a domestically abundant and secure source of energy, the use of natural gas also offers a number of environmental benefits over other sources of energy, particularly other fossil fuels. This text will discuss the environmental effects of natural gas in terms of emissions as well as the environmental impact of the natural gas industry itself.

Natural gas is the cleanest of all the fossil posed primarily of methane, the main products of the combustion of natural gas are carbon dioxide and water vapour. The same compounds we exhale when we breathe. Coal and oil are composed of much more complex molecules, with a higher carbon ratio and higher nitrogen and sulfur contents. This means that when combusted, coal and oil release higher levels of harmful emissions, including a higher ratio of carbon emissions, nitrogen oxides (NOx), and sulfur dioxide (SO2). Coal and fuel oil also release ash particles into the bstances that do not burn are carried into the atmosphere and contribute to pollution. The combustion of natural gas, on the other hand, releases very small amounts of sulfur dioxide and nitrogen oxides, virtually no ash or particulate matter, lower levels of carbon dioxide, carbon monoxide, and other reactive hydrocarbons.

Natural gas, emitting fewer harmful chemicals into the atmosphere than other fossil fuels, can help to mitigate some environmental issues. Global warming or the ‘greenhouse effect’ is an environmental issue that deals with the potential for global climate change due to increased levels of atmospheric ‘greenhouse gases’. There are certain gases in our atmosphere that serve to regulate the amount of heat that is kept close to the Earth’s surface. Scientists theorize that an increase in these greenhouse gases will translate into increased temperatures around the globe, which would result in many disastrous environmental effects. In fact, the Intergovernmental Panel on Climate Change (IPCC) predicts in its ‘Third Assessment Report’ released in February 2001 that over the next 100 years global average temperatures will rise by between 0,15 – 4,7 C0 (2.4 and 10.4 degrees Fahrenheit).

The principle greenhouse gases include water vapour, carbon dioxide, methane, nitrogen oxides, and some engineered chemicals such as chlorofluorocarbons. The reduction of greenhouse gas emissions has become a primary focus of environmental programs in countries around the world. One of the principle greenhouse gases is carbon dioxide. Although carbon dioxide does not trap heat as effectively as other greenhouse gases. The volume of carbon dioxide emissions into the atmosphere is very high, particularly from the burning of fossil fuels.

Reducing carbon dioxide emissions can play a huge role in combating the greenhouse effect and global warming. The combustion of natural gas emits almost 30 percent less carbon dioxide then oil, and just under 45 percent less carbon dioxide than coal. Methane, the principle component of natural gas, is itself a very potent greenhouse gas. In fact, methane has an ability to trap heat almost 21 times more effectively than carbon dioxide. Sources of methane emissions include the waste management, operations industry, the agricultural industry, as well as leaks and emissions from the oil and gas industry itself. A major study performed by the Environmental Protection Agency (EPA) and the Gas Research Institute (GRI) discovered that increased use of natural gas in the place of other, dirtier fossil fuels can serve to lessen the emission of greenhouse gases.

Exercise 3. Match the English - Ukrainian equivalents.

1)  pollution 2)  fossil fuels 3)  greenhouse gas 4)  emission 5)  pollutant 6)  particulate matter 7)  carbon dioxide 8)  environment 9)  nitrogen oxide 10) waste management

a)  неефективне управління b)  забруднююча речовина c)  двоокис вуглецю d)  навколишнє середовище e)  пил f)  викопне пальне g)  забруднення h)  окис азоту i)  парниковий газ j)  викид

Exercise 4. Answer the questions on text 1.

1. Why is natural gas the cleanest of all the fossil fuels? 2. Why is coal and oil combustion harmful for environment? 3. What would result in many disastrous environmental effects? 4. How are greenhouse gases formed? 5. Why can the increased use of natural gas serve to lessen the emission of greenhouse gases?

Exercise 5. Memorize the following words and word combinations to text 2.

acid rain – кислотний дощ

emission profiles – параметри, характеристики емісії

volatile – летючий; такий, що швидко випаровується

lungs – легені

vehicle – транспортний засіб

smokestack – трубний дим

solvent – розчинник

utility – пристрій; pl. utilities – комунальні споруди

shift – зміна, зміщення

particulate matter – пил

harmful – шкідливий

Exercise 6. Read and translate the text.

Text 2. Smog as an environmental problem

Smog and poor air quality is a pressing environmental problem, particularly for large metropolitan cities. Smog is formed by a chemical reaction of carbon monoxide, nitrogen oxides, volatile organic compounds and heat from sunlight. Smog and ground level ozone can contribute to respiratory problems ranging from temporary discomfort to long-lasting permanent lung damage. Pollutants contributing to smog come from a variety of sources, including vehicle emissions, smokestack emissions, paints and solvents. As the reaction to create smog requires heat, smog problems are the worst in the summertime.