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Файл:Jet Propulsion Engine Fundamentals английский язык для студентов специальности «Проектирование авиационных и ракетных двигателей». Учебное пособие
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Task 12. Answer the questions and use them as a plan for retelling the text.
1. What do the propellants constitute?
2. What does the term liquid propellant embrace?
3. What does a biopropellant rocket unit contain?
4. What does a monopropellant contain?
5. What chemical properties do monopropellants possess?
6. What differentiates different kinds of propellants?
Task 13. Translate the following sentences into English.
1. В ЖРД развитие тяги создается необходимыми компонентами
оборудования и ракетным топливом.
2. В ЖРД имеются одна или несколько камер сгорания, один или несколько
топливных баков, механизм подачи топлива, источник его питания,
топливопровод и устройства управления.
3. Ракетный двигатель может дополнительно оснащаться системой
управления вектором тяги, различными измерительными приборами и
содержать остаточное количество топлива.
4. Конструкция силовой установки обусловлена ее назначением, скоростью
полета, желаемыми траекториями полета, минимальным ресурсом,
уязвимостью, моментами управления положением или количеством блоков,
которые необходимо построить и доставить.
5. Требования, предъявляемые к ракетному двигателю, включают профиль
тяговой характеристики, вид топлива, количество камер сгорания, суммарный
импульс, количество запусков, минимальный уровень надежности и некоторые
другие.
6. Существуют две категории ракетных двигателей: двигатели,
используемые для увеличения коммерческой нагрузки и передаче ей
значительно большей скорости, а также вспомогательная силовая установка,
используемая для корректировки траектории и управления положением.
7. ЖРД могут быть многоразовыми и одноразовыми, с возможностью
повторного или однократного запуска.
8. В камере сгорания ЖРД жидкое топливо дозируется, впрыскивается,
распыляется, смешивается и сгорает.
9. Горение топлива сопровождается образованием высокотемпературных
продуктов газовой реакции, которые, ускоряясь, выбрасываются с большой
скоростью, чтобы развить силу тяги.
10. В ЖРД используются два типа систем подачи топлива: система,
использующая насосы для подачи топлива от топливного бака до камеры
сгорания, и система, использующая газ под высоким давлением для
перемещения топлива и топливного бака.
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Task 14. Find the Russian equivalents for the English terms.
1. duty cycle
2. propulsion system
3. attitude control
4. upper stage
5. propellant
6. combustion chamber
7. control device
8. matter
9. tank
10. launch vehicle
11. cold gas propellant
12. adjustment
13. thrust vector control
14. residual propellant
15. valve
16. instrumentation
17. vulnerability
18. pump
19. package
20. altitude-performance
21. cryogenic propellant
22. torque
23. hardware component
24. liquified gas
25. throttle
26. vaporization losses
27. cooling jacket
28. bipropellant rocket unit
29. thrust-time
30. feed mechanism
31. gelled propellant
32. additive
1. компонент оборудования
2. топливный бак
3. момент
4. летные характеристики
5. насос
6. ракетный двигатель с раздельной
подачей компонентов топлива
7. подающий механизм
8. криогенное топливо
9. силовая установка
10. устройство управления
11. сжиженный газ
12. измерительные приборы
13. тяговая характеристика
14. регулирование тяги
15. охлаждающая рубашка
16. уязвимость
17. ракетное топливо
18. разгонный блок
19. корректировка
20. клапан
21. невыработанное топливо
22. вещество
23. управление положением
24. топливо из холодного газа
25. аппаратура
26. желатинизированное ракетное
топливо
27. режим работы
28. камера сгорания
29. управления вектором тяги
30. ракета-носитель
31. присадка
32. потери от испарения
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Task 15. Look through the texts (Task 7, 11) and find key sentences in each
paragraph.
Task 16. Write a summary to the text (Task 7)
Task 17. Sum up the text (Task 11).
Task 18. Skim the text and try to understand its subject matter.
PROPELLANT FEED SYSTEMS
The propellant feed system has two principal functions: to raise the pressure of
the propellants and to feed them to one or more thrust chambers. The energy for these
functions comes either from a high-pressure gas, centrifugal pumps, or a combination
of the two. The selection of a particular feed system and its components is governed
primarily by the application of the rocket, duration, number or type of thrust
chambers, past experience, mission, and by general requirements of simplicity of
design, ease of manufacture, low cost, and minimum inert mass. All feed systems
have piping, a series of valves, provisions for filling and removing (draining and
flushing) the liquid propellants, and control devices to initiate, stop, and regulate their
flow and operation.
In general, a pressure feed system gives a vehicle performance superior to a
turbopump system when the total impulse or the mass of propellant is relatively low,
the chamber pressure is low, the engine thrust-to-weight ratio is low (usually less
than 0.6), and when there are repeated short-duration thrust pulses; the heavy-walled
tanks for the propellant and the pressurizing gas usually constitute the major inert
mass of the engine system. In a turbopump feed systems the propellant tank pressures
are much lower (by a factor of 10 to 40) and thus the tank masses are much lower
(again by a factor of 10 to 40). Turbopump systems usually give a superior vehicle
performance when the total impulse is large (higher ∆u) and the chamber pressure is
higher. The pressurized feed system can be relatively simple, such as for a singleoperation, factory-preloaded, simple unit (with burst diaphragms instead of some of
the valves), or quite complex, as with multiple restartable thrusters or reusable
systems. If the propulsion system is to be reusable or is part of a manned vehicle
(where the reliability requirements are very high and the vehicle’s crew can monitor
and override automatic commands), the feed system becomes more complex (with
more safety features and redundancies) and more expensive. The pneumatic
(pressurizing gas) and hydraulic (propellant) flows in a liquid propellant engine can
be simulated in a computer analysis that provides for a flow and pressure balance in
the oxidizer and the fuel flow paths through the system. Some of these analyses can
provide information on transient conditions (filling up of passages) during start, flow
decays at cutoff, possible water hammer, or flow instabilities.
(Sutton, George P. & Biblarz, Oscar Rocket Propulsion Elements: an introduction to
the engineering of rockets)
43
Task 19. Choose the right variant to fill in the gap.
1. The propellant feed system has two principal functions: to raise … of the
propellants and to feed them to one or more thrust chambers.
a) the velocity
b) the thrust
c) the pressure
2. The energy for the propellant feed system to perform its functions comes either
from …
a) a high-pressure gas, centripetal pumps, or a combination of the two.
b) a high-pressure gas, centrifugal pumps, or a combination of the two.
c) a high-pressure fluid, centrifugal pumps, or a combination of the two.
3. Among of the factors the selection of a particular feed system and its
components depends on are …
a) application of the rocket, energy source, number or type of thrust chambers,
past experience, mission.
b) application of the rocket, duration, number or type of control devices, past
experience, mission.
c) application of the rocket, duration, number or type of thrust chambers, past
experience, mission.
4. A pressure feed system gives a vehicle performance superior to …
a) a turboprop system
b) a turbopump system
c) a turbofan system
5. Turbopump systems usually give a superior vehicle performance when …
a) the total impulse is large and the chamber pressure is low.
b) the total impulse is large and the chamber pressure is higher.
c) the total impulse is low and the engine thrust-to-weight ratio is higher.
6. The pneumatic and hydraulic flows in … can be simulated in a computer
analysis that provides for a flow and pressure balance in the oxidizer and the fuel
flow paths through the system.
a) a liquid propellant engine
b) a solid propellant engine
c) a thermochemical engine
Task 20. Collect all the possible supplementary information on the theme of Unit
4 and present it to your groupmates.
UNIT 5. Gas Pressure Feed Systems
TEXT: GAS PRESSURE FEED SYSTEMS
Grammar: The Gerund
Task 1. Study the forms and functions of the Gerund in the English sentences and
translate them into Russian.
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Forms
Active
Passive
Simple
writing
being written
Perfect
having written
having been written
The function of the Gerund
Example
Object
The check valves prevent mixing of the
oxidizer with the fuel when the unit is not
in an upright position.
Attribute
Additional components for separating
the liquid from the pressurizing gas are
often incorporated.
Adverbial
The propellants are fed to the thrust
chamber by opening valves.
abort – аварийное прекращение
запуска, отмена старта
bladder – мембрана
check valve – клапан контроля,
запорный клапан
controlled propellant discharge –
регулируемый расход ракетного
топлива
docking – стыковка
feed line - топливопровод
gas pressure feed system –
pitch – тангаж
pressure regulator – регулятор
давления
pressure sensor – датчик давления
pressurized feed system –
вытеснительная система подачи
to pressurize the propellant – подавать
компоненты ракетного топлива
вытеснением
propellant valve – топливный клапан
Reaction Control System – реактивная
Task 2. Find the Gerund in the English sentences and translate them into Russian.
Pay attention to the ways it is expressed in Russian sentences.
1. There are two categories, namely those used for boosting a payload and
imparting a significant velocity increase to a payload, and auxiliary propulsion for
trajectory adjustments and attitude control.
2. One of the simplest and most common means of pressurizing the propellants is
to force them out of their respective tanks by displacing them with high-pressure gas.
3. With monopropellants the gas pressure feed system becomes simpler, since
there is only one propellant and not two, reducing the number of pipes, valves, and
tanks.
4. Electrical heaters are provided at propellant valves, certain lines, and injectors
to prevent fuel freezing or moisture forming into ice.
Task 3. Study the following words and word combinations and learn them by heart.
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вытеснительная система подачи с
использованием порохового
аккумулятора
gauge – датчик
man-rated – пилотируемый,
управляемый человеком
Orbital Maneuver System – система
орбитального маневра (СОМ)
orbit circularization – обращение по
орбите
orbit insertion – вывод на орбиту
система управления (РСУ)
rendezvous – встреча, сближение
residue – остаток
roll - крен
to scavenge – продувать
starting valve – пусковой клапан
single-shot – одноразовый
translation maneuver – маневр
разгона; маневр изменения орбиты
unit – зд. двигатель
yaw – рыскание
Task 4. Translate the words into Russian. Mind suffixes and prefixes.
Respect – respective, charge – discharge, simple – simplicity, flex – flexible, remote –
remotely, complete – completely, to eliminate – elimination, to add – addition, possible –
possibly, to expand – expandable, to provide – provision, to apply – application, to orbit – to
deorbit, safe – safety, ride – override, to rely – reliable – reliability
Task 5. Read and translate the following international words.
Regulator, filter, elastic, sensor, constant, position, line, variation, combination,
component, maneuver, orbital, reaction, rendezvous, correction, automatic, status, helium,
period, nominal, impulse
Task 6. Translate the sentences into Russian using the terms from Task 3.
1. A simple pressurized feed system consists of a high-pressure gas tank, a gas
starting valve, a pressure regulator, propellant tanks, propellant valves, and feed lines.
2. Additional components, such as filling and draining provisions, check valves,
filters, flexible elastic bladders for separating the liquid from the pressurizing gas,
and pressure sensors or gauges, are also often incorporated.
3. If a unit is to be used over and over, such as space-maneuver rocket, it will
include several additional features such as, possibly, a thrust-regulating device and a
tank level gauge; they will not be found in an expendable, single-shot unit, which
may not even have a tank-drainage provision.
4. The Reaction Control System provides thrust for attitude control (in pitch, yaw,
and roll) and for small-vehicle velocity corrections or changes in almost any direction
(translation maneuvers), such as are needed for rendezvous and docking; it can
operate simultaneously with or separate from the Orbital Maneuver System.
46
Task 7. Read the following text carefully paying attention to the words in bold
type. Try to understand the subject matter of the text and be ready to answer the
following questions.
1. What is one of the simplest and most common means of pressurizing the
propellant?
2. What does a simple pressurized feed system consist of?
3. What additional components could a simple pressurized feed system contain?
4. How does a simple pressurized feed system operate?
5. What do the variations in a simple pressurized feed system depend on?
6. What does Orbital Maneuver System provide?
7. What does Reaction Control System provide?
GAS PRESSURE FEED SYSTEMS
(Part 1)
One of the simplest and most common means of pressurizing the propellants is
to force them out of their respective tanks by displacing them with high-pressure gas.
This gas is fed into the propellant tanks at a controlled pressure, thereby giving a
controlled propellant discharge. Because of their relative simplicity, the rocket
engines with pressurized feed systems can be very reliable.
A simple pressurized feed system consists of a high-pressure gas tank, a gas
starting valve, a pressure regulator, propellant tanks, propellant valves, and feed
lines. Additional components, such as filling and draining provisions, check valves,
filters, flexible elastic bladders for separating the liquid from the pressurizing gas,
and pressure sensors or gauges, are also often incorporated. After all tanks are
filled, the high-pressure gas valve is remotely actuated and admits gas through the
pressure regulator at a constant pressure to the propellant tanks. The check valves
prevent mixing of the oxidizer with the fuel when the unit is not in an upright
position. The propellants are fed to the thrust chamber by opening valves. When the
propellants are completely consumed, the pressurizing gas can also scavenge and
clean lines and valves of much of the liquid propellant residue. The variations in this
system, such as the combination of several valves into one or the elimination and
addition of certain components, depend to a large extent on the application. If a unit
is to be used over and over, such as space-maneuver rocket, it will include several
additional features such as, possibly, a thrust-regulating device and a tank level
gauge; they will not be found in an expendable, single-shot unit, which may not even
have a tank-drainage provision. With monopropellants the gas pressure feed system
becomes simpler, since there is only one propellant and not two, reducing the number
of pipes, valves, and tanks.
In a complex man-rated pressurized feed system, the combined Space Shuttle
Orbital Maneuver System (OMS) and the Reaction Control System (RCS), the
OMS provides thrust for orbit insertion, orbit circularization, orbit transfer,
rendezvous, deorbit, and abort. The RCS provides thrust for attitude control (in
47
pitch, yaw, and roll) and for small-vehicle velocity corrections or changes in almost
the high-pressure gas valve; propellant discharge; an upright position; thrust
chamber; by displacing; a simple pressurized feed system; pressure; the pressure
regulator; the oxidizer; pressurizing
A simple pressurized feed system
consists of …
admits gas through the pressure regulator
at a constant pressure to the propellant
tanks.
If a unit is to be used over and over it will
include …
depend to a large extent on the
application.
any direction (translation maneuvers), such as are needed for rendezvous and
docking; it can operate simultaneously with or separate from the OMS.
(Sutton, George P. & Biblarz, Oscar Rocket Propulsion Elements: an introduction to
the engineering of rockets)
Task 8. Find in the text the English equivalents for the following words and word
combinations.
Газ под высоким давлением, топливный бак, вытеснять, регулируемый
расход ракетного топлива, надежный, топливопровод, при постоянном
давлении, предотвращать смешивание, окислитель, камера сгорания, клапан,
продувать, остаточное количество жидкого компонента ракетного топлива,
регулятор тяги, датчик уровня топлива в баке, дренаж топливного бака, смена
орбиты, уход с орбиты, скорость, вертикальное положение.
Task 9. Fill in the gaps with missing words and translate the sentences into
Russian.
1. One of the simplest and most common means of ___________the propellants
is to force them out of their respective tanks ________ them with high-pressure gas.
2. High-pressure gas is fed into the propellant tanks at a controlled __________,
thereby giving a controlled__________.
3. __________consists of a high-pressure gas tank, a gas starting valve, a
pressure regulator, propellant tanks, propellant valves, and feed lines.
4. After all tanks are filled, _________is remotely actuated and admits gas
through __________at a constant pressure to the propellant tanks.
5. The check valves prevent mixing of __________with the fuel when the unit is
not in_________.
6. The propellants are fed to __________ by opening valves.
Task 10. Complete the sentences with appropriate endings.
48
Electrical heaters are provided at
propellant valves, certain lines, and
injectors …
a high-pressure gas tank, a gas starting
valve, a pressure regulator, propellant
tanks, propellant valves, and feed lines.
After all tanks are filled, the highpressure gas valve is remotely actuated
and …
are duplicated and redundant; if one fails,
another can still complete the mission.
Electrical lead wires to the propellant
valves are wrapped around the chamber
and nozzle; …
several additional features such as,
possibly, a thrust-regulating device and a
tank level gauge.
Several key components, such as all the
helium pressure regulators, propellant
tanks, some valves, and about half the
thrusters …
a burnout will quickly melt the wire and
cut the power to the valve, which will
return to the spring-loaded closed
position and shut off the propellant flow.
The variations in this system, such as the
combination of several valves into one or
the elimination and addition of certain
components …
to prevent fuel freezing or moisture
forming into ice.
Task 11. Read the following text and try to understand its subject matter.
Translate the text into Russian. Use the dictionary if necessary.
GAS PRESSURE FEED SYSTEMS
(Part II)
OMS and RCS feature various redundancies, an automatic RCS thruster selection
system, various safety devices, automatic controls, sensors to allow a display to the
Shuttle’s crew of the system’s status and health, and manual command overrides. The
reliability requirements are severe. Several key components, such as all the helium
pressure regulators, propellant tanks, some valves, and about half the thrusters are
duplicated and redundant; if one fails, another can still complete the mission. It is
possible to feed up to 1000 lbm (pound-mass) of the liquid from the large OMS
propellant tanks to the small RCS ones, in case it is necessary to run one or more of
the small reaction control thrusters for a longer period and use more propellant than
the smaller tanks allow; it is also possible to feed propellant from the left aft system
to the one on the vehicle's right side, and vice versa. These features allow for more
than nominal total impulse in a portion of the thrusters, in case it is needed for a
particular mission mode or an emergency mode.
The compartmented steel propellant tanks with antislosh and antivortex baffles,
sumps, and a surface tension propellant retention device allow propellant to be
delivered independent of the propellant load, the orientation, or the acceleration
environment (some of the time in zero-g). Gauges in each tank allow a determination
49
of the amount of propellant remaining, and they also indicate a leak. Safety features
include sniff lines at each propellant valve actuator to sense leakage. Electrical
heaters are provided at propellant valves, certain lines, and injectors to prevent fuel
freezing or moisture forming into ice.
A typical RCS feature that enhances safety and reliability is a self-shutoff device
in small thrusters that will cause a shutdown in case they should experience
instability and burn through the walls. Electrical lead wires to the propellant valves
are wrapped around the chamber and nozzle; a burnout will quickly melt the wire and
cut the power to the valve, which will return to the spring-loaded closed position and
shut off the propellant flow.
(Sutton, George P. & Biblarz, Oscar Rocket Propulsion Elements: an introduction to
the engineering of rockets)
Task 12. Answer the questions and use them as a plan for retelling the text.
1. What is it necessary for OMS and RCS to have various redundancies?
2. In what cases is it necessary to feed up to 1000 lbm of the liquid from the large
OMS propellant tanks to the small RCS ones?
3. What allows propellant to be delivered independent of the propellant load, the
orientation, or the acceleration environment?
4. What do gauges in each tank determine and indicate?
5. What is used to prevent fuel freezing or moisture forming into ice?
6. How could a self-shutoff device enhance safety and reliability of RCS?
7. Why could the propellant valve return to the spring-loaded position and shut off the
propellant flow?
Task 13. Translate the following sentences into English.
1. Одним из самых распространенных способов подачи ракетного топлива
вытеснением является вытеснение его из топливных баков посредством
замещения газом под высоким давлением.
2. Регулируемый расход ракетного топлива обеспечивается за счет подачи в
топливные баки газа при регулируемом давлении.
3. Относительная простота ракетных двигателей с вытеснительной системой
подачи топлива делает их очень надежными.
4. Вытеснительная система подачи топлива включает бак для газа высокого
давления, баки для ракетного топлива, топливные клапаны и топливопроводы.
5. После заполнения баков ракетным топливом дистанционно активируется
клапан подачи газа под высоким давлением, и газ под постоянным давлением
начинает поступать в топливные баки через регулятор давления.
6. Запорные клапаны предотвращают перемешивание топлива и окислителя
в тех случаях, когда двигатель не находится в вертикальном положении.
7. Открытие клапанов обеспечивает подачу компонентов ракетного топлива
в камеру сгорания.
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