Учебно методический комплекс

Stack

The flue gas stack is a cylindrical structure at the top of all the heat transfer chambers. The breeching directly below it collects the flue gas and brings it up high into the atmosphere where it will not endanger personnel.

The stack damper contained within works like a butterfly valve and regulates draft (pressure difference between air intake and air exit) in the furnace, which is what pulls the flue gas through the convection section. The stack damper also regulates the heat lost through the stack. As the damper closes, the amount of heat escaping the furnace through the stack decreases, but the pressure or draft in the furnace increases which poses risks to those working around it if there are air leakages in the furnace, the flames can then escape out of the firebox or even explode if the pressure is too great.

breech – боров (дымоход)

endanger – подвергать опасности

work – механизм, конструкция

butterfly valve – дроссельный клапан

GRAMMAR

Task 13

Put the following questions into the correct order.

1. fuel, does, where, flow, into?

2. be, how, burners, can, mounted?

3. the, what, radiant, is, section, known, as, section?

4. fluid, the, does, through, pass, where, heating?

5. designs, why, most, a, section, do, convection, include, furnace?

Task 14

Translate the following sentences paying attention to italicized grammar

It is (was) … that (which, who)

Именно …

!!!Remember:

1. The design of the furnace depends considerably upon the fuel to be burned.

2. It is the turbulence that gives an effective combustion.

3. The heated fluid is circulated round the whole plant to heat exchangers to be used wherever heat is needed.

Task 15

Give the English equivalents to the Russian words.

1. The incoming fuel-air mixtures (должна нагреваться) above the ignition temperature.

2. Fuel (сжигается) with air provided from an air blower.

3. Burners (могут быть) floor mounted, wall mounted or roof mounted.

4. The heat (передается) mainly by radiation to tubes around the fire in the chamber.

5. The heating fluid passes through the tubes and (нагревается) to the desired temperature.

WRITING

Task 16

Write a summary of the text “Household furnaces”.

A household furnace is a major appliance that is permanently installed to provide heat to an interior space through intermediary fluid movement, which may be air, steam or hot water. The most common fuel source for modern furnaces in the United States is natural gas; other common fuel sources include LPG (Liquefied petroleum gas), fuel oil, coal, or wood. In some cases electrical resistance heating is used as the source of heat, especially where the cost of electricity is low.

Combustion furnaces always need to be vented to the outside. Traditionally, this was through a chimney, which tends to expel heat along with the exhaust. Modern high-efficiency furnaces can be 98% efficient and operate without a chimney. The small amount of waste gas and heat are mechanically ventilated through a small tube through the side or roof of the house.

Modern household furnaces are classified as condensing or non-condensing based on their efficiency in extracting heat from the exhaust gases. Furnaces with efficiencies greater than approximately 89% extract so much heat from the exhaust that water vapor in the exhaust condenses; they are referred to as condensing furnaces. Such furnaces must be designed to avoid the corrosion that this highly acidic condensate might cause and may need to include a condensate pump to remove the accumulated water. Condensing furnaces can typically deliver heating savings of 20% - 35% assuming the old furnace was in the 60% Annual Fuel Utilization Efficiency (AFUE) range.

ПО ПРЕДМЕТУ:

«ТЕХНИКА СЦЕНЫ И СЦЕНОГРАФИЯ»

Министерство образования и науки Российской Федерации

Белгородский государственный институт культуры

Дата добавления: 2014-12-24