Focused Practice

I. Answer the following questions:

1. What work is underway?

2. How long must the containers provide isolation of the fuel?

3. How many container concepts are under investigation? What are they?

4. What are the principal objectives of the program of container concepts?

5. Do container design considerations include remote fabrication and handling requirements?

6. What was the assessment of metals and alloys based on?

II. Analyse the grammar structures underlined in the above text.

III. Speak on: The development of different container concepts.

Unit 50 Grammar: The Infinitive. The Subjective Infinitive Construction. The Participle as an Attribute Word List:

1. LNG (Liquified Natural Gas)	сжиженный природный газ
2. to prevent	предотвратить, избежать
3. contamination	заражение, загрязнение
4. crude oil	сырая нефть
5. on the contrary	наоборот
6. to be meaningless	не иметь значения
7. conventional	традиционный
8. heat engine	тепловой двигатель
9. heating / cold media	теплые/холодные среды
10. working fluid	рабочая среда
11. ambient temperature	температура окружающей среды
12. coolant	охладитель
13. exergy	эксергия, термодинамическая функция, вырабатывание электроэнергии на основе использования разности температур
14. to reject	удалять
15. a thermocouple	термопара
16. to apply	применять

Exergy Analysis on Power Plants Using Cold Energy of lng

Recently, liquified natural gases (LNGes) are paid attention to as fuel oils. LNG will be used increasingly as the town gas and heat sources in urban regions, because LNG is useful to prevent contamination of atmospheric air. However, LNG needs seven times more energy to be transported than crude oil, because of necessity to be liquified and kept in cold state. A large quantity of cold energy in LNG is not used so efficiently except a small part of it. On the contrary, some plants consume energy to heat for gasification of LNG. This is meaningless and wasteful for conservation of energy.

At present, the cold energy is used for liquification of oxygen and nitrogen, freezing of foods, cold destruction and low temperature transmission of electricity.

In conventional heat engines, the heating media (working fluids) are heated to high temperature and sent to the engines to generate power, and then cooled until ambient temperature. There are effective plants to operate in the higher temperature.

However, the plants generating power with cold energy have to be operated in such mechanisms as follows:

1) At first, the cold media (coolants) are cooled and raised of their exergy and then supplied to the plants to generate power and at last, warmed up to near ambient temperature. Such plants have not yet been invented to our regret.

2) Another practical plants generating power with cold energy are heat engines which are operated in cold environment kept cold media. The working fluids are supplied to the engines at high pressure and near ambient temperature, and drive the turbines to generate power, and then rejected at low pressure and cold temperature. These types of power generation are called heat engines in cold atmosphere.

3) The thermocouples working between cold and ambient (or higher) temperatures can generate power. But, the materials used are not yet developed enough, so the exergy efficiency of power generation is very low, at present.

Heat engines in cold atmosphere are thought to have many types.