TEPREL is a family of

rocket engine A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accorda ...

s designed and built by the Spanish aerospace company

PLD Space Payload Aerospace S.L. (PLD Space) is a Spanish company developing two partially-reusable launch vehicles called Miura 1 and Miura 5. Miura 1 is designed as a sounding rocket for sub-orbital flights to perform research or technology development ...

for their

Miura 1 Miura 1 (previously called Arion 1) is a suborbital recoverable launch vehicle developed by the Spanish company PLD Space. It is planned to be the first recoverable launch vehicle in Europe. The first launch is currently scheduled for the 15 J ...

and

Miura 5 Miura 5 is a two-stage European orbital recoverable launch vehicle of the Spanish company PLD Space currently under development. Miura 5 will be 24.9 m long, capable of inserting 900 kg of payload into a low Earth orbit (LEO), featuring an ...

launch vehicles. The TEPREL engine, named after the Spanish reusable engine program that is financing its development, uses

kerosene Kerosene, paraffin, or lamp oil is a combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in aviation as well as households. Its name derives from el, κηρός (''keros'') meaning "wax", and was regi ...

and

liquid oxygen Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an app ...

as propellants. So far, several versions of this engine, intended to propel

, have been developed and tested on the company's own liquid propulsion test facilities located in

Teruel Teruel () is a city in Aragon, located in eastern Spain, and is also the capital of Teruel Province. It has a population of 35,675 in 2014 making it the least populated provincial capital in the country. It is noted for its harsh climate, with ...

, Spain.

Revisions

In the first versions of the engine the propellants are driven to the engine by using a pressure-fed cycle with

helium Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. ...

. Later versions of the engine (TEPREL-C) incorporate a

turbopump A turbopump is a propellant pump with two main components: a rotodynamic pump and a driving gas turbine, usually both mounted on the same shaft, or sometimes geared together. They were initially developed in Germany in the early 1940s. The purpo ...

TEPREL-DEMO

The TEPREL-DEMO engine, originally called NetonVac1, was first tested in 2015. It is a calorimetric engine model, intended to demonstrate combustion stability as well as to acquire relevant information such as ignition and shut-down sequences, pressures and temperatures along the engine, thrust and propellant mass flow rates at different thrust profiles. Additionally, the engine served to test all associated hardware and software at PLD Space Propulsion Test Facilities. The engine is capable to produce a thrust of 28 kN at sea level.

TEPREL-A

With the TEPREL-A engine, first tested in 2017, the company included several design upgrades, such as a new

combustion chamber A combustion chamber is part of an internal combustion engine in which the fuel/air mix is burned. For steam engines, the term has also been used for an extension of the firebox which is used to allow a more complete combustion process. Intern ...

design, an improved injector geometry and a regenerative cooling system. The later enables the engine to fire for nearly 2 minutes, which is the envisaged nominal functioning duration for the suborbital launch vehicle

. At sea level, the engine produces a thrust of 32 kN.

TEPREL-B

TEPREL-B is the first flight version of the TEPREL engine. Several design improvements have been implemented to reduce the overall weight of the engine. It is equipped with a thrust-vector-control system and a convergent-divergent nozzle, all regeneratively cooled. In May 2019 the first unit of this model was destroyed during a test. After a long investigation PLD Space concluded that the problem was due to excess pressure during engine start at ignition. PLD Space addressed the issue through a combination of improvements to the launch site infrastructure and procedural improvements. It is currently fully operational. In February 2020, PLD Space successfully completed a 122-second test that allowed it to achieve flight rating. On August 28, 2020,

completed required tests for the thrust vector control system on the Teprel-B rocket engine.

TEPREL-C

Flight version of the TEPREL engine to be used in the

rocket. Initially it was expected to produce 105.5 kN of thrust at sea level. Later expected thrust was increased to 190 kN.

TEPREL-C vacuum

Version of TEPREL-C adapted to vacuum, and capable of re-ignition in microgravity conditions. Capable of 45 kN of thrust.

References

{{Rocket engines Rocket engines using kerosene propellant Spacecraft propulsion Space program of Spain Rocket engines using the gas-generator cycle