2020-07-12
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break point — предел
cam — кулачок
Camshaft — распределительный вал
cause — вызывать
combustion chamber — камера сгорания
compression — сжатие
compression stroke — такт сжатия
cu rrent — поток
to deprive of — лишать
detriment — ущерб
displacement — смещение
distinction — различие
closed — замкнутый
exhaust — выхлоп, выхлопной
faaust stroke — такт выхлопа
exhaust valve — выпускной клапан
to exit — выходить, покидать
to expand — расширять
friction — трение
fuel — топливо
to generate — создавать
intake manifold — всасывающий патрубок
intake stroke — такт впуска
intake valve — впускной клапан
in particular — в особенности
performance — производительность
piston — поршень
piston rod — шатун
power stroke — рабочий такт, рабочий ход
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to pull — тянуть
reciprocating — возвратно-поступательный, поршневой
to reduce — сокращать
to release — выпускать
residual — остаточный
rocker arm — коромысло
to rub — тереть
sequence — последовательность
smooth — плавный
spark plug — свеча зажигания
to suck in — всасывать
sweep — зд. прохождение
to tend — иметь тенденцию
torque — крутящий момент
to transfer — передавать
water jacket — водяная рубашка
tq.yield — предоставлять
to tend — иметь тенденцию
Otto cycle — 4-тактный цикл работы ДВС, предложенный немецким инженером Н. Отто в 1876 г.
1. Choose the right word and fill in the gaps:
1. The internal combustion engine is based on the... of gas and air.
a) ventilation
b) oxidation
c) absorbtion
2. Gases of high temperature and pressure are permitted....
a) to compress
b) to vaporize
c) to expand
3. A piston is a device designed for... movements.
a) reciprocating
b) rotating
c) circulating
4. The Otto cycle comprises... strokes.
a) two
b) four
c) five
5. When the... valve is open fuel is drawn into the combustion chamber,
a) exhaust
b) transfer
c) intake
6. The hot gas does work on the piston during the... stroke,
a) power
b) compression
c) exhaust
7. Having more pistons the engine generates more internal....
a) combustion
b) friction
c) ignition
2. Find in the text equivalents to the following phrases:
Происходить в ограниченном пространстве, наиболее значительное различие, сжатие внутри цилиндра, непрерывное горение, реактивный двигатель, газовая турбина, ключевые компоненты, полезная работа выполняется, единичное продвижение поршня вдоль цилиндра, синхронизация открытия и закрытия клапанов, когда объем становится наименьшим, производить искру, очистить цилиндр от отработанных продуктов горения, снижать эффективность топлива, тишать двигатель некоторой мощности.
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3. Find the English equivalents for the following Russian words:
1) камера
a) chandler
b) chamber
c) chamfer
2) выпускной
a) exist
b) exhibit
c) exhaust
3) искра
a) sparkle
b) spark
c) sprinkle
4) сжимать
a) to compress
b) to combine
c) to coincide
5) клапан
a) valve
b) value
c) valet
6) такт
a) strike
b) stroke
c) streak
7) смесь
a) mixing
b) mixible
c) mixture
8) последовательность
a) consequence
b) sequel
c) sequence
9) топливо
a) fuel
b) fume
c) full
10) объем
a) voluble
b) volute
c) volume
11) мощность
a) power
b) powder
c) pouter
12) трение
a) fiction
b) faction
c) friction
Divide text into logical parts and give each a suitable title.
5. Fill in the gaps with the words from the box:
power generate electricity combustion outside meant
The fundamental difference between an engine and a motor is that motor converts 1)_________into mechanical energy whereas an engine converts thermal energy into mechanical energy. At one time, the word ‘engine’ (from Latin ingenium ----- ‘ability’) 2)_________any piece of machinery. A ‘motor’ (from Latin motor — ‘mover’) is any machine that produces mechanical 3)_______ Traditionally electric motors are not referred to as ‘engines’, but 4)___________ engines are often referred to as ‘motors’. However, many people consider engines as those things which 5)________their power from within, and motors as requiring an 6)___________ source of energy to perform their work.
Ignition System
All internal combustion engines must achieve ignition in their cylinders to create combustion and can be classified by their ignition system. The point in the cycle at which the fuel/oxidizer mixture is ignited has a direct effect on the efficiency and output of the ICE. For a typical 4 stroke automobile engine, the burning mixture has to reach its maximum pressure when the crankshaft is 90 degrees after top dead centre. Leaner mixtures and lower mixture pressures bum more slowly requiring more advanced ignition timing. In the past outside flame and hot-tube systems were used. Nikola Tesla gained one of the first patents on the mechanical ignition system with the US patent, ‘Electrical Igniter for Gas Engines’, on 16 August, 1898. Today most engines use an electrical or compression heating system for ignition. Typically engines use either a spark ignition (SI) method or a compression ignition (Cl) system. Ignition components generally include spark plugs, ignition wires, distributor cap, distributor rotor, distributor, ignition coil, ignition module and primary circuit triggering device.
For ignition management, the system also relies on the power train control module (PCM), which also manages other engine functions. The names and exact use of ignition components varies widely among different makes and models. For example, many ignition systems no longer use a distributor and consequently do not have any of its related parts. As a team, the ignition components work together to sense engine position and conditions and provide a spark inside the engine’s cylinders at precisely the right instant.
Electrical or gasoline-type ignition systems (that can also run on other fuels) generally rely on a combination of a lead-acid battery and an induction coil to generate a high-voltage electrical spark to ignite the air-fuel mix in the engine’s cylinders. This battery can be recharged during operation using an electricity-generating device, such as an alternator or generator driven by the engine. Gasoline engines take in a mixture of air and gasoline, compress to less than 185 psi and use a spark plug to ignite the mixture when it is compressed by the piston head in each cylinder.
Compression ignition systems, such as the diesel engine and HCCI engines, rely solely on heat and pressure created by the engine in its compression process for ignition. Compression that occurs is usually more than three times higher than in a gasoline engine. Diesel engines will take in air only, and shortly before peak compression, a small quantity of diesel fuel is sprayed into the cylinder via a fuel injector that allows the fuel to instantly ignite. HCCI type engines will take in both air and fuel but will continue to rely on an unaided auto-combustion process due to higher pressures and heat. This is also why diesel and HCCI engines are also more susceptible to cold starting issues though they will run just as well in cold weather once started. Most diesels also have battery and charging systems however this system is secondary and is added by manufacturers as luxury for ease of starting, turning fuel on and off which can also be done via a switch or mechanical apparatus, and for running auxiliary electrical components and accessories. Most old engines, however, rely on electrical systems that also control the combustion process to increase efficiency and reduce emissions.
HCCI has characteristics of the two most popular forms of combustion used in IC engines: homogeneous charge spark ignition (gasoline engines) and stratified charge compression ignition (diesel engines). As in homogeneous charge spark ignition, the fuel and oxidizer are mixed together.
However, rather than using an electric discharge to ignite a portion of the mixture, the concentration and temperature of the mixture are raised by compression until the entire mixture reacts simultaneously. Stratified charge compression ignition also relies on temperature increase and concentration resulting from compression, but combustion occurs at the boundary of fuel-air mixing, caused by injection.
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The defining characteristic of HCCI is that the ignition occurs at several places at a time which makes the fuel/air mixture bum nearly simultaneously. There is no direct initiator of combustion. This makes the process inherently challenging to control. However, with advances in microprocessors and a physical understanding of the ignition process, HCCI can be controlled to achieve gasoline engine like emissions along with diesel engine like efficiency. In fact, HCCI engines have been shown to achieve extremely low levels of nitrogen oxide emissions (NOx) without treatment by catalytic converter. The unburned hydrocarbon and carbon monoxide emissions are still high due to lower peak temperatures, as in gasoline engines, and must still be treated to meet automotive emission regulations.
Refer to your maintenance suggestions for recommended service for the ignition system. The speed of the flame front is directly affected by compression ratio, fuel mixture temperature and octane or cetane rating of the fuel. Modern ignition systems are designed to ignite the mixture at the right time to ensure the flame front doesn’t contact the descending piston crown. If the flame front contacts the piston, pinking or knocking results. An engine that runs rough, bucks, surges, stalls, gets poor fuel economy or fails an emissions test are all signs of a potential ignition system problem. Although some cars now use platinum spark plugs with 100,000-mile service life, other parts such as ignition wires still need attention and periodic replacement. If your car exhibits any symptoms such as those mentioned here, be alert. If the glowing or light appears on the dashboard, you should have its cause investigated by a professional technician at your earliest opportunity. If the light flashes, the condition is more severe and must be checked out immediately to prevent damage to the catalytic converter.
