Chapter 6. Solar collector (приемник солнечной энергии) — КиберПедия 

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Chapter 6. Solar collector (приемник солнечной энергии)

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Exercise 1. Read and translate the text, using the words below.

Solar collector is a device to transform the sun energy into more usable or storable form. The energy of sunlight is transformed into electromagnetic radiation from infra-red (long) waves into ultraviolet (short) ones. The solar energy striking the earth's surface depends on many factors such as weather conditions, location and orientation of the surface. It averages about 1000 watts per square meter under clear sky with the surface directly perpendicular to the sun's rays.

The solar heating system consists of the collector described above; a heat transfer circuit that includes the fluid and the means to circulate it; and a storage system including a heat exchanger (if the fluid circulating through the collector is not the same liquid being used to heat the object of the system). The system may or may not include secondary distribution of heat among different storage reservoirs or users of heat. The system can be used in a variety of ways, including warming domestic hot water, heating swimming pools, heating water for a radiator or floor-coil heating circuit, heating an industrial dryer, or providing input energy for a cooling system. The heat is normally stored in car parks. Heat storage is usually intended to cover a day or two's requirements, but other concepts exist including seasonal storage (where summer solar energy is used for winter heating by raising the temperature by a few degrees of several million liters of water).

There are two common systems of solar heating of domestic hot water: thermo siphon and pumped. In the thermo siphon system a storage tank is placed above the collector. As the water in the collector is heated, it will rise and naturally start to circulate around the tank. This system is self-regulating and requires no moving parts or external energy that is why it is very attractive. Its main drawback is the need for the tank to be placed at the level higher than the collector, which may prove to be physically difficult. A pumped system uses a pump to circulate the water, so the tank can be positioned independently of the collector location. This system requires external energy to run the pump. It also requires control electronics to measure the temperature gradient across the collector and modulate the pump accordingly.

Solar collectors can be mounted on a roof or wall, facing the equator. So a north-facing roof in the southern hemisphere and a south-facing roof in the northern hemisphere are ideal. Collectors are usually angled at the latitude of the location. Depending on sunshine available, 2 to 10 square meter array may provide 50 - 60% of the hot water heating required for a typical family house. Such systems are a secondary feature of sustainable housing, since space heating and hot water are usually the largest single consumer of energy in households.

A solar thermal collector that stores heat energy is called a "batch" type system. Other types of solar thermal collectors do not store energy but instead use fluid circulation (usually water or an antifreeze solution) to transfer the heat for direct use or storage in an insulated reservoir. Water/glycol has a high thermal capacity and is therefore convenient to handle. The direct radiation is captured using a dark colored surface which absorbs the radiation as heat and conducts it to the transfer fluid. Metal is a good thermal conductor, especially copper and aluminum. In high performance collectors a "selective surface" is used in which the collector surface is coated with a material having properties of high-absorption and low-emissivity. The selective surface reduces heat-loss caused by infrared radiant emission from the collector to ambient.

As it heats up, thermal losses from the collector itself will reduce its efficiency, resulting in increased radiation, primarily infrared. This is countered in two ways. First, a glass plate is placed above the collector plate which will trap the radiated heat within the airspace below it. This exploits the so-called greenhouse effect, which is in this case a property of the glass: it readily transmits solar radiation in the visible and ultraviolet spectrum, but does not transmit the lower frequency infrared radiation very well. The glass plate also traps air in the space, thus reducing heat losses by convection. The collector housing is also insulated below and laterally to reduce its heat loss. The second way to improve efficiency is by cooling the absorber plate. This is done by ensuring that the coldest heat transfer fluid is circulated through the absorber and with a sufficient flow rate. The fluid carries away the absorbed heat, thus cooling the absorber. The warmed fluid leaving the collector is either directly stored, or else passes through a heat exchanger to warm another tank of water, or is used to heat a building directly. The temperature differential across an efficient solar collector is usually only 10 or 20°C. While a large differential may seem impressive, it is in fact an indication of a less efficient design.

Solar collectors transform solar radiation into heat and transfer that heat to a medium (water, solar fluid, or air). Then solar heat can be used for heating water, to back up heating systems or for heating swimming pools.

 

Words to be remembered.

dryer –сушильный аппарат (сушилка)
pump – насос; работать насосом; накачивать, выкачивать
tank – цистерна, бак
drawback - недостаток
modulate – модулировать
hemisphere – полушарие
angle - угол
latitude - широта
batch – группа, комплект
to coat - покрывать
infra-red - инфракрасный
to average – в среднем равняться
circuit - цепь
fluid - жидкость
heat exchanger - теплообменник
solar heating system – солнечная система отопления
heat storage – тепловой аккумулятор/накопление теплоты
storage reservoir – водохранилище/резервуар для хранения
glycol - гликоль
thermal capacity - теплоёмкость
emissivity – коэффициент излучения
ambient – окружающая среда
glass plate – стеклянная пластина
to exploit - использовать
greenhouse effect – парниковый эффект
convection - конвенция
absorber - поглотитель
flow rate – расход/интенсивность подачи (кислорода)
heat transfer– теплопередача
absorbed heat – поглощённое тепло
to back up - поддерживать
to mount – устанавливать, монтировать

 

Exercise 2. Answer the following questions.

1) What is solar collector?
2) What does solar energy striking the Earth’s surface depend on?
3) How can the solar heating system be used?
4) Why is the thermo siphon system considered to be more attractive?
5) Are there any drawbacks?
6) Why is water convenient to handle?
7) What is a good thermal conductor?

Exercise 3. Make up special questions to the following statements.

1) The selective surface reduces heat-loss caused by infrared radiation emission from the collector to ambient. (What...?)
2) A glass plate is placed above the collector plate. (Where...?)
3) The fluid carries away the absorbed heat. (What...?)
4) There are two common systems of solar heating of domestic hot water. (How many...?)
5) Solar collectors can be mounted on a roof or wall, facing the equator. (Where...?)

 

Exercise 4. Say whether the statements are true or false. Correct them if necessary.

1) The energy of sunlight is transformed into electromagnetic radiation from ultraviolet waves into infra-red ones.
2) The solar energy striking the Earth’s surface doesn’t depend on the location and orientation of the surface.
3) The system can’t include secondary distribution of heat among different storage reservoirs.
4) There are two common systems of solar heating of domestic hot water: thermo siphon and pumped.
5) The pump in a pumped system can be positioned independently of the collector location.
6) Copper and aluminum are bad thermal conductors.
7) The next way to improve efficiency is by heating the absorber plate.

 

Exercise 5. Insert the omitted words.

1) Solar collector is a... to transform the sun energy into more usable or storable form.
2) Heat... is usually intended to cover a day or two’s requirements.
3) This system is self-relating and... no moving parts or... energy.
4) Its main... is the need for the tank to be placed at the level higher than the collector.
5) Other types of solar thermal collectors use... circulation (usually water or antifreeze...) to transfer heat.
6) In high performance collectors a “selective surface” is used in which the collector surface is … with a material having properties of... and....
7) This exploits the so – called... effect.

(fluid, greenhouse, storage, low-emissivity, device, requires, high-absorption, external, drawback, coated, solution).

Exercise 6. Find the proper English equivalents to the given Russian terms.

1. инфракрасный 1. to back up
2. недостаток 2. flow rate
3. жидкость 3. absorbed heat
4. теплообменник 4. infra-red
5. парниковый эффект 5. thermal capacity
6. поддерживать 6. drawback
7. коэффициент излучения 7. heat exchanger
8. интенсивность подачи кислорода 8. greenhouse effect
9. поглощённое тепло 9. emissivity
10. теплоёмкость 10. fluid

 

Exercise 7. Find the proper Russian equivalents to the given English terms.

1. southern hemisphere 1. домашнее хозяйство
2. conduct 2. окружающая среда
3. copper 3. накопительная цистерна
4. household 4. поглощающая пластина
5. self-regulating system 5. проводить
6. transmit 6. медь
7. absorber plate 7. южное полушарие
8. storage tank 8. передавать
9. ambient 9. саморегулируемая система

 

Exercise 8. Make up5 sentences of your own with the words from ex-s 6 and 7.

Exercise 9. What does the word in italics mean in the following sentences? Consult the text.

1) It requires control electronics to measures the temperature gradient across the collector.
2) It is a good thermal conductor.
3) This exploits the so-called greenhouse effect.
4) This is countered in two ways.
5) It has a high thermal capacity and is therefore convenient to handle.
6) It can be mounted on a roof or wall, facing the equator.

Exercise 10. Find in the text sentences with the verb in Passive Voice and translate them.

Exercise 11. Retell the text.

UNIT IV

 

СHAPTER 1. RUSSIA – THE SEA STATE (РОССИЯ – ВЕЛИКАЯ МИРОВАЯ ДЕРЖАВА)

Exercise 1. Read and translate the text, using the words below.

Russia is a sea power. Russia possesses the powerful port complex which is one of the most stable and dynamically developing sector of the countries economy. Russia belongs to the number of large sea powers with interests in international navigation and active on sea transport communications.

The length of the sea boarder of the Russian federation is 38.8 thousand km.. Russia has a direct excess to three oceans. Russia has a powerful port potential. The total portal line length of Russian ports and other transloading terminals is about 80000 running meters. It allows to handle 600 vessels simultaneously.

The main port potential of the country is concentrated in 44 Commercial Sea Ports which are members of the Association of Sea Ports of Russia and 120 different commercial structures are used for cargo transloading operations.

Russian sea ports are mainly deep water with specialized transloading complexes with the most modern equipment. The handling capacity of the ports constitutes 215.0 mln. tons per year and is used at 70 percent. The country`s demand in foreign trade cargoes shipment via sea ports constituted 244.0 mln. tons in 2000. The use of Russian sea ports capacities comes to 70 percent.

Constant work has been carried out with the Ministry of Railroad transportation and State Customs committee of Russia, republics administrations, as well as districts and areas, city administrations in Russia, cargo owners, forwarders, to attract cargo flows to Russian ports, to speed up the cargo passage via transport junctions to perfect tariff policy while passing the cargoes via the sea ports.

Development of sea transport material and technical basis (of the port fleet) is mainly determined by the State demand in the sea coastal navigation and foreign trade shipment. Dynamics of the sea shipment development reflects the condition of the countries economy to a large extent as well as Russia`s desire to integrate into the world economic system and its reaction to a constant strengthening competition of the world commodity and transport markets.

It`s necessary to point out that 38.2 percent of all Russian cargoes are handled in the ports of the Black and Azov Sea basins and 35.9 percent – in the ports of the Baltic basin. The ports of the Far East basin account for 19.2 percent, Nothern basin – 5.2 percent, Caspian basin – 1.5 percent of all the cargoes. 50 percent of cargoes are handled via the ports of the Baltic states and Finland in the Baltic basin. 19.8 percent of cargoes are handled in the ports of the Ukraine in the Black Sea – Azov basin. The reason of such a high share of the ports of neighbouring countries in the Baltic basin is in the lack of powerful specialized complexes in Russian ports for liquid bulk cargoes handling as well as in containers. But the ports of the Baltic states have such complex built at the times of the USSR which are operating quite effectively.

 

Words to be remembered.

to possess - обладать

stable - стабильный

to belong to - принадлежать к чему-л.

excess - выход, доступ

portal line - причальная линия

transloading terminal - перегрузочный терминал

simultaneously - одновременно

to handle - обрабатывать

handling capacity - пропускная способность

to constitute - составлять

demand - потребность

shipment - перевозка

via - через

forwarder - экспедитор

to attract - привлекать

cargo flows - грузовые потоки

to speed up - ускорять

to reflect - отражать

to point out - отметить, выделять

basin - бассейн

lack - отсутствие

coastal navigation shipment - каботажные перевозки

 

Exercise 2. Answer the following questions.

1. What does Russia possess?

2. Has our country interests in international navigation?

3. Russia hasn`t a direct excess to three oceans, has it?

4. How many vessels can our ports handle simultaneously?

5. What is the handling capacity of the port?

6. Development of sea transport material and technical basis is mainly determined by the State demand, isn`t it?

7. What does the Port Authority do to attract cargo flows to Russian ports?

8. Where are all Russian cargoes handled?

9. What is the reason of a high share of the ports of neighbouring countries in the Baltic basin?

10. Has Russia a powerful port potential?

 

Exercise 3. Read the international words and guess their meaning.

dynamically, navigation, total, potential, association, committee, policy, commodity, transport junctions, cargo owners.

 

Exercise 4. Find the equivalents to the following words and word combinations in the text.

Развитие морского транспорта, мощный портовый комплекс, пропускная способность, морская держава, так же как, соседние страны, грузовладельцы, экспедитор, перевозка грузов, обработка грузов, длина портальных линий, перегрузочные комплексы, потребность страны.

 

Exercise 5. Make up your own sentences, using the word combinations from ex. 4.

 

Exercise 6. Say whether the statements are true or false. Correct them if necessary.

1. Russian port complex is not one of the most stable and dynamically developing sector of the countries economy.

2. Russia has a direct excess to three oceans.

3. The total portal line length of Russian ports and other transloading terminals handle 400 vessels simultaneously.

4. 35 Commercial Sea Ports are members of the Association of Sea Ports of Russia.

5. Russian sea ports are mainly deep water with specialized transloading complexes.

6. Dynamics of the sea shipment development reflects the condition of the countries economy.

7. All Russian cargoes are handled in the ports of the Caspian basin.

8. Russian ports has not lack of powerful specialized complexes for liquid bulk cargoes handling.

9. The ports of the Baltic states have such specialized complexes which are operating quite effectively.

10. Russia is a sea power.

 

Exercise 7. Find the proper Russian equivalents to the given English terms.

1. stable грузовые потоки
2. еxcess через
3. portal line пропускная способность
4. transloading terminal перевозка
5. to handle излишек, избыток
6. handling capacity причальная линия
7. to constitute экспедитор
8. shipment каботажные перевозки
9. via перегрузочный терминал
10. forwarder обрабатывать
11. cargo flows отсутствие
12. to point out составлять
13. lack отметить
14. coastal navigation shipment стабильный

Exercise 8. Translate the following sentences from Russian into English.

1. Портовый комплекс является одним из наиболее стабильных и динамично развивающихся секторов экономики страны.

2. Российские морские порты имеют специальные перегрузочные комплексы.

3. Основной портовый потенциал сосредоточен в 44 морских торговых портах.

4.Существует проблема отсутствия достаточно мощных специализированных комплексов в российских портах.

5. Развитие морского транспорта определяется потребностью страны в морских каботажных и внешнеторговых перевозках.

6. Постоянно проводится работа по привлечению грузопотоков в порты, ускорению прохождения грузов через транспортные узлы, совершенствованию тарифной политики при прохождении грузов через морские порты.

 

Exercise 9. Retell the text.

CHAPTER 2. FAMOUS WORLD PORTS (ИЗВЕСТНЫЕ ПОРТЫ МИРА)

Exercise 1. Read and translate the text, using the words below.


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