Ex.3. Match word combinations from Ex.2.with its Russian equivalent.

Хранение энергии, избыточное тепло, поглощающие охладители, значительно сниженный, лежит по большей части, общие проблемы, долгосрочные инвестиции, сотрудничество между заинтересованными лицами, относительно большой, очевидно трудно.

Read the text and define the core points. Write the summery of it.

District cooling systems are becoming a more common part of the energy supply systems, also in cooler parts of the world such as Scandinavia. The systems are mainly made in densely populated areas or large facilities as airports, military and university campuses. The usual design approach for DC systems does not normally include transient analyses when designing DH and DC systems.

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DC systems are in many ways very similar to DH systems. Both systems use water as main energy transport medium and comprise components such as pipes, fittings, valves and heat exchanges. The energy is, however, produced differently, e.g. boilers, CHP (combined heat and power) for DH systems and e.g. electric chillers or absorption chillers for cooling systems. Compared to DH systems, the temperature difference at the consumers is much lower in DC

systems. Typically, DH systems are designed for temperature differences of 35- СибАДИ40 °C with supply temperatures of 70 – 90 °C, whereas DC systems are designed for temperature differences around 10 °C or lower temperatures of 4.5 – 6 °C.

The low temperature difference in cooling systems results in relatively high water flow compared to amount of supplied power.

With increased velocity there is a higher risk of critical pressure transients in the system. Consider a soft plastic 1\2” garden hose with water flowing inside. The water is then suddenly cut off by releasing the grip on the sprayer pistol, the hose twists and wiggles for a short time. What happens inside the hose is that, at the time the grip is released on the sprayer pistol, the water in motion is suddenly stopped, resulting in an increased water pressure at the sprayer pistol – like a train when it hits an obstacle, each car is slamming into the one ahead. Water is nearly incompressible, and therefore the soft garden hose expands a bit, resulting in a lower pressure increase compared to e.g. a pipe of steel.

Consider the same scenario as described, but instead of cutting off the water flow with a sprayer pistol at the end of the hose, the water is cut off by closing the valve at the other end of the hose. This will lead to a sudden pressure drop just after the valve (the train cars are pulled apart).

Now consider that instead of 1\2” garden hose we have a rigid steel pipe with a diameter of 1, 000 mm. The same physics apply, when the water in motion is suddenly stopped, the pressure increases or decreases. Because of the dimension of the steel pipe, and because of the steel pipe rigidity, the forces that are now at work are much, much greater that in normal operation. In fact, the forces can be so strong that the pressure inside the steel pipe can exceed both the lower and the upper pressure limits of DC system, risking failure of pipes and other system components.

To investigate the risk of exceeding the pressure limits of the system and facing a reduced lifetime of the system or in worst case ruptured pipes or ruined pumps, detailed flow and pressure analyses are performed – safety analyses.

Ex.1. True or false.

1.The systems are mainly made in poorly populated areas.

2.The usual design approach for DC systems normally includes transient analyses.

3.It is normal practice in COWI to include transient analyses.

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Ex.3. Match word combinations from Ex.2.with its Russian equivalent.

Превысит лимит давления, густо населенный, размер стальной трубы, увеличение / уменьшение давления, гидравлическая система распределения, теплообменники, пистолет (распылитель), отсекающий клапан, перекручивание напорного рукава, возросшая циркуляция.

Ex.4. Choose the correct answer.

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6. … systems use … as main energy transport medium.

LESSON 10. THE MIDDLE EAST

Read the text and define the core points. Write the summery of it.

District cooling m the Middle East «is driven by growing governments» environmental awareness, as well as shortage and high cost of power. District cooling is getting more and more anchored as the most viable cooling solution in the Middle East where temperatures frequently exceed 45 degree Celsius and air-conditioning consumes almost 60-70% of the electricity during periods of peak demand. Most of us agree by now that old-fashioned air conditioning units mounted on building walls and balconies result in unsightly blemishes on any building. They can make even the most attractive, welldesigned architectural buildings look ugly. Besides proven to use large amounts of electricity to produce a relatively limited cod ng effect, they are noisy and occupy valuable space in commercial premises. According to figures from Euroheat & Power, centralized district cooling set-ups are more than five times

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as energy-efficient as traditional single-unit air-conditioning. In contrast, modern district cooling represents a paradigm shift in ensuring efficient comfortable indoor environments all year around.

The region's rapidly expanding industrial base and population have increased the demand for power, which averages an annual growth rate of nearly 5% average. The rising air conditioning needs account for almost 70% of this growth in power demand. As power shortage is rampant in this region, the

СибАДИgovernments are turning to district cooling to cool buildings, which has proved itself as a less expensive and greener alternative to air conditioning This solution can both mitigate the power crisis in in the Gulf Cooperation Council (GCC) region and help to reduce carbon footprints through increased energy efficiency and lower CO2 emissions.

That said, it is important to note that providing the required cooling effect from a central facility efficiently does set higher standards to efficient high performing cooling plants and a reliable distribution network to consumers in such extreme ail year ambient temperatures.

Centralized supply via a network of purposeful and customized factory insulated pipe systems in which there is hardly any loss of thermal energy is a must to make it possible to achieve substantial economies of scale. Such insulated pipes supplement the rest of a system of advanced technologies designed basically to operate and perform in an environmentally aware mode during the whole process, from production of cooling to distribution all the way to end consumers, efficiently.

A major concern in the region has been that district coding also requires a lot of water, which, like electricity, is relatively limited and therefore, expensive in the GCC region. Currently, district coding plants use potable water, but the search is on for technologies that will allow them to use non-desalinated seawater. Even though a few plants are already using seawater, the corrosionresistant equipment needed will increase their already expensive equipment cost. As part of their green initiatives and to encourage saving of water resources and protect the environment the government of Dubai issued specific directives to reduce the consumption of desalinated water in cooling processes.

Ex.1. True or false.

1. DC is getting less anchored in the middle east.

2. Air conditioning consumes 60 % of the electricity during peak demand. 3. Old fashioned air conditioning blemishes on any building.

4. Old fashioned air conditioning systems are noisy.

5. Centralized central cooling set ups are three times as energy efficient as traditional.

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6.The region’s expanding has increased the demand for power.

7.The rising air conditioning needs account for 70%.

8.The power shortage in region is low.

9.The governments are turning to DH.

10.Industrialized buildings supplement the rest of advanced technologies.

Ex.3. Match word combinations from Ex.2.with its Russian equivalent.

Обеспокоенность состоянием окружающей среды, высокая стоимость, жизнеспособное решение, воздушное кондиционирование потребляет, установленные на стенах здания, ежегодный уровень роста, наибольшее потребление, надежная сеть распределения, индивидуально адаптированная система трубопровода, внешняя температура.

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