RD-701
Encyclopedia
RD-701 - liquid-fuel rocket engine
developed by Energomash
, Russia
. It was proposed to propel the reusable MAKS space plane
before cancellation of this project. The RD-701 is a tripropellant engine that uses staged combustion cycle
afterburning of oxidizer-rich hot turbine
gas. This engine has two modes: the first one - Mode #1 - uses three components with fuel
mixture of RP-1
/ LH2 which is applied for near earth surface conditions; the second one - Mode #2 - uses LH2 in vacuum where atmosphere influence is negligible; both of modes uses LOX
as an oxidizer.
The use of less dense fuel components at maximum efficiency
conditions allows minimizing the volume of fuel tanks and subsequently their mass down to 30%. As of 2009 the engine is characterized by highest value of pressure, 300 bar
, ever used in combustion chamber
of rocket engines when running in Mode #1 with mixture of fuel components. The RD-701 became the base model for RD-704 with one combustion chamber.
(mass flow — 73.7 kg/s), LH2 (mass flow — 29.5 kg/s) and LOX
(mass flow — 388.4 kg/s). This mode is applied in lower atmosphere to minimize fuel tanks volume. The total thrust for altitude 10 km is 2х1,890.2 KN and specific impulse is 3,845 m/s.
The second mode uses just two components: LH2 (mass flow — 24.7 kg/s) and LOX
(mass flow — 148.5 kg/s). This mode applied for near space conditions and gives thrust 2х784.5 KN, specific impulse — 4,532 m/s.
The mixing block of the main combustion chamber has three groups of injectors, one for each of the three available components. When running in Mode #2 the engine doesn't use the kerosene group. The engine uses regenerative cooling
by liquid hydrogen
.
Rocket engine
A rocket engine, or simply "rocket", is a jet engineRocket Propulsion Elements; 7th edition- chapter 1 that uses only propellant mass for forming its high speed propulsive jet. Rocket engines are reaction engines and obtain thrust in accordance with Newton's third law...
developed by Energomash
NPO Energomash
NPO Energomash “V. P. Glushko” is a Russian manufacturer originated from design bureau, which focuses primarily on the development and production of liquid propellant rocket engines. NPO Energomash is based in Moscow, with satellite facilities in Samara, Perm, and St. Petersburg, and employs close...
, Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
. It was proposed to propel the reusable MAKS space plane
MAKS space plane
The MAKS is a cancelled Russian air-launched orbiter project that was proposed in 1988, but cancelled in 1991. The orbiter was supposed to reduce the cost of transporting materials to Earth orbit by a factor of ten...
before cancellation of this project. The RD-701 is a tripropellant engine that uses staged combustion cycle
Staged combustion cycle (rocket)
The staged combustion cycle, also called topping cycle or pre-burner cycle, is a thermodynamic cycle of bipropellant rocket engines. Some of the propellant is burned in a pre-burner and the resulting hot gas is used to power the engine's turbines and pumps...
afterburning of oxidizer-rich hot turbine
Turbine
A turbine is a rotary engine that extracts energy from a fluid flow and converts it into useful work.The simplest turbines have one moving part, a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades, or the blades react to the flow, so that they move and...
gas. This engine has two modes: the first one - Mode #1 - uses three components with fuel
Fuel
Fuel is any material that stores energy that can later be extracted to perform mechanical work in a controlled manner. Most fuels used by humans undergo combustion, a redox reaction in which a combustible substance releases energy after it ignites and reacts with the oxygen in the air...
mixture of RP-1
RP-1
RP-1 is a highly refined form of kerosene outwardly similar to jet fuel, used as a rocket fuel. Although having a lower specific impulse than liquid hydrogen , RP-1 is cheaper, can be stored at room temperature, is far less of an explosive hazard and is far denser...
/ LH2 which is applied for near earth surface conditions; the second one - Mode #2 - uses LH2 in vacuum where atmosphere influence is negligible; both of modes uses LOX
Lox
Lox is salmon fillet that has been cured. In its most popular form, it is thinly sliced—less than in thickness—and, typically, served on a bagel, often with cream cheese, onion, tomato, cucumber and capers...
as an oxidizer.
The use of less dense fuel components at maximum efficiency
Specific impulse
Specific impulse is a way to describe the efficiency of rocket and jet engines. It represents the derivative of the impulse with respect to amount of propellant used, i.e., the thrust divided by the amount of propellant used per unit time. If the "amount" of propellant is given in terms of mass ,...
conditions allows minimizing the volume of fuel tanks and subsequently their mass down to 30%. As of 2009 the engine is characterized by highest value of pressure, 300 bar
Bar (unit)
The bar is a unit of pressure equal to 100 kilopascals, and roughly equal to the atmospheric pressure on Earth at sea level. Other units derived from the bar are the megabar , kilobar , decibar , centibar , and millibar...
, ever used in combustion chamber
Combustion chamber
A combustion chamber is the part of an engine in which fuel is burned.-Internal combustion engine:The hot gases produced by the combustion occupy a far greater volume than the original fuel, thus creating an increase in pressure within the limited volume of the chamber...
of rocket engines when running in Mode #1 with mixture of fuel components. The RD-701 became the base model for RD-704 with one combustion chamber.
Specifications
Two-chamber RD-701 has two modes. The first one uses three components: RP-1RP-1
RP-1 is a highly refined form of kerosene outwardly similar to jet fuel, used as a rocket fuel. Although having a lower specific impulse than liquid hydrogen , RP-1 is cheaper, can be stored at room temperature, is far less of an explosive hazard and is far denser...
(mass flow — 73.7 kg/s), LH2 (mass flow — 29.5 kg/s) and LOX
Lox
Lox is salmon fillet that has been cured. In its most popular form, it is thinly sliced—less than in thickness—and, typically, served on a bagel, often with cream cheese, onion, tomato, cucumber and capers...
(mass flow — 388.4 kg/s). This mode is applied in lower atmosphere to minimize fuel tanks volume. The total thrust for altitude 10 km is 2х1,890.2 KN and specific impulse is 3,845 m/s.
The second mode uses just two components: LH2 (mass flow — 24.7 kg/s) and LOX
Lox
Lox is salmon fillet that has been cured. In its most popular form, it is thinly sliced—less than in thickness—and, typically, served on a bagel, often with cream cheese, onion, tomato, cucumber and capers...
(mass flow — 148.5 kg/s). This mode applied for near space conditions and gives thrust 2х784.5 KN, specific impulse — 4,532 m/s.
The mixing block of the main combustion chamber has three groups of injectors, one for each of the three available components. When running in Mode #2 the engine doesn't use the kerosene group. The engine uses regenerative cooling
Regenerative cooling
Regenerative cooling in rockets is where some or all of the propellant is passed through tubes, channels or otherwise in a jacket around the combustion chamber or nozzle to cool the engine because the fuel in particular and sometimes the oxidizer are good coolants...
by liquid hydrogen
Liquid hydrogen
Liquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be...
.
RD-704
The RD-704 is a smaller version of basic engine and uses the same components and scheme of work but with one preburner, turbopump, combustion chamber and nozzle.See also
- MAKS space planeMAKS space planeThe MAKS is a cancelled Russian air-launched orbiter project that was proposed in 1988, but cancelled in 1991. The orbiter was supposed to reduce the cost of transporting materials to Earth orbit by a factor of ten...
- Staged combustion cycleStaged combustion cycle (rocket)The staged combustion cycle, also called topping cycle or pre-burner cycle, is a thermodynamic cycle of bipropellant rocket engines. Some of the propellant is burned in a pre-burner and the resulting hot gas is used to power the engine's turbines and pumps...
- RD-170 - RP-1RP-1RP-1 is a highly refined form of kerosene outwardly similar to jet fuel, used as a rocket fuel. Although having a lower specific impulse than liquid hydrogen , RP-1 is cheaper, can be stored at room temperature, is far less of an explosive hazard and is far denser...
/LOXLoxLox is salmon fillet that has been cured. In its most popular form, it is thinly sliced—less than in thickness—and, typically, served on a bagel, often with cream cheese, onion, tomato, cucumber and capers...
Russian engine - RD-0120 - LH2/LOXLoxLox is salmon fillet that has been cured. In its most popular form, it is thinly sliced—less than in thickness—and, typically, served on a bagel, often with cream cheese, onion, tomato, cucumber and capers...
Russian engine
External links
- Engines of MAKS: RD-701
- B.I. Gubanov. Triumph and tragedy of "Energia", Chapter 40: Engines of reusable systems. (in Russian)
- Astronautix: RD-701
- Astronautix: RD-704
- NPO «Energomash»: News of ... 19 June 2007year (in Russian)