Jan C. Deeken

German Aerospace Center (DLR) | DLR · Institute of Space Propulsion

Anomaly detection in multivariate timeseries is used in various domains, such as finance, IT, or aerospace, to identify irregular behavior in the used applications. Prior research in anomaly detection has focused on estimating the joint probability of all variables. Then, anomalies are scored based on the probability they receive. Thereby, the vari...

Traditional experimental design methods often face challenges in handling complex aerospace systems due to the high dimensionality and nonlinear behavior of such systems, resulting in nonoptimal experimental designs. To address these challenges, machine learning techniques can be used to further increase the application areas of modern Bayesian Opt...

The development of modern reusable launchers, such as the Themis project with its LOX/LCH4 Prometheus engine, CALLISTO—a reusable VTVL-launcher first-stage demonstrator with a LOX/LH2 RSR2 engine, and SpaceX’s Falcon 9 with its Merlin 1D engine, underscores the need for advanced control algorithms to ensure reliable engine operation. The multi-rest...

With the development of contemporaneous reusable launchers, including projects such as Themis with a liquid LOX/LCH4 Prometheus engine, CALLISTO - Reusable VTVL launcher first stage demonstrator with a LOX/LH2 RSR2 engine, or Space-X’s Falcon 9 with a Merlin 1 engine, it is essential to further advance control algorithms to secure a failure- free e...

Accurate calculations of the heat transfer and the resulting maximum wall temperature are essential for the optimal design of reliable and efficient regenerative cooling systems. However, predicting the heat transfer of supercritical methane flowing in cooling channels of a regeneratively cooled rocket combustor presents a significant challenge. Hi...

Abstract—Reusability of LREs in Europe is increasingly attracting the attention of scientific community and industry with leading projects such as THEMIS, CALLISTO (reusable demonstrators for vertical take-off and landing (VTVL)) and Ariane Next – all powered by the reusable cryogenic Oxygen/Methane (LOX/LCH4) engine “Prometheus”. To enable further...

To increase liquid rocket engines (LREs) lifetime capability and allow for reusability applications, the efficient evaluation of the most critical subcomponents' remaining useful life plays a vital role. Regeneratively cooled combustion chamber (CC) wall must withstand extremely high loads emerging from a massive temperature gradient between the ho...

With the LUMEN (Liquid upper stage demonstrator engine) project, DLR is aiming to develop, build and operate a breadboard engine based on an expander bleed cycle scheme. The propellants for LUMEN will be liquid oxygen (LOX) and liquid natural gas (LNG). LUMEN will be a modular breadboard engine to be used on DLR test benches such as the P8.3 test f...

Nowadays reusability of LREs, represented in projects such as CALLISTO and Maїa (both including the re-usable Prometheus engine), is seen not only as essential in the effort to prepare competitive future European space access, but also sets a new requirement towards high reliability engineering standards. With engine operation life in excess of a s...

The DLR project LUMEN (liquid upper stage demonstrator engine) aims at developing, building and operating a modular LOx/LNG breadboard engine in the thrust range of 10 kN to 30 kN with a total lifetime of more than 7200 s over multiple ignitions [1]. Since these characteristics meet the main requirements for recently proposed lunar lander missions...

Within the presented manuscript the focus is towards maturing damage propagation simulation models of the regeneratively cooled combustion chamber (CC) inner liner, to gain an in-depth understanding of the interactions between influential elements including elevated temperature, cyclic conditions and the fatigue life mechanisms. A coupled thermal a...

Overview of DLRs additive Manufacturing activities in space propulsion and satellites

The DLR LUMEN (Liquid upper stage demonstrator engine) project aims to develop and test a modular bread-board demonstrator to deepen the understanding of the operational behaviour of rocket engine systems. The demonstrator engine includes two separate turbopumps for Liquid Oxygen (LOX) and Liquified Natural Gas (LNG) supply. At the DLR Institute of...

With the LUMEN (Liquid upper stage demonstrator engine) project, DLR is aiming to develop, build and operate a breadboard engine based on an expander bleed cycle scheme. The propellants for LUMEN will be liquid oxygen (LOX) and liquid natural gas (LNG). LUMEN will be a modular breadboard engine to be used on DLR test benches such as the P8.3 test f...

Within the scope of the European Green Deal, the aerospace industry is currently staking on sustainability. To fulfil the objectives and in order to ensure Europe's independent and cost-effective space access capabilities, the ASCenSIon (Advancing Space Access Capabilities - Reusability and Multiple Satellite Injection) project, funded by H2020, i...

This paper describes the tool created for design and optimize supersonic partial admission impulse turbine for LRE [ 1 ] application, which is commonly used in open cycle applications, while focusing on the models used to better predict the operational conditions of turbines for small thrust range engines. Also, the tool for turbine blade profile g...

Nowadays, liquid rocket engines use closed-loop control at most near-steady operating conditions. The control of the transient phases is traditionally performed in open loop due to highly nonlinear system dynamics. This situation is unsatisfactory, in particular for reusable engines. The open-loop control system cannot provide optimal engine perfor...

The LUMEN project (Liquid upper stage demonstrator engine) has fostered the development of a LOX (OTP) and LNG (FTP) turbopump at the DLR Lampoldshausen. In this work we will give on overview on the current status of the turbopumps.

Intelligent engine control could be one of the most important innovations in the development of future reusable engines, facilitating a safer and more economical engine operation. In this work, we investigate the closed-loop control of the LUMEN expander-bleed engine by combining machine learning with a transient simulation environment. The control...

The last years have witnessed an enormous interest in the use of artificial intelligence methods, especially machine learning algorithms. This also has a major impact on aerospace engineering in general, and the design and operation of liquid rocket engines in particular, and research in this area is growing rapidly. The paper describes current mac...

The DLR project LUMEN (liquid upper stage demonstrator engine) aims at developing and operating a modular LOX/LNG bread-board engine in the 25 kN thrust class for operation at the new P8.3 test facility in Lampoldshausen[1, 2]. The main focus of this project is to strengthen DLR’s competence on rocket engine system level as well as to enable tests...

Identifying the optimal design of a new launch vehicle is most important because design decisions made in the earlydevelopment phase limit the later performance of the vehicles and determine the associated costs. Reusing the firststage via retropropulsive landing increases the complexity even more. Therefore, an optimization framework forpartially...

The last years have witnessed an enormous interest in the use of artificial intelligence methods, especially machine learning algorithms. This also has a major impact on aerospace engineering in general, and the design and operation of liquid rocket engines in particular , and research in this area is growing rapidly. The paper describes current ma...

The LUMEN project (liquid upper stage demonstrator engine) at the DLR Institute of Space Propulsion has the goal of producing a bread-board demonstrator engine powered by LOX/LNG. In this paper the flame anchoring at the shear-coaxial injectors is investigated in function of operational load points by optical probes. The combustion chamber pressure...

The LUMEN project (liquid upper stage demonstrator engine) at the DLR Institute of Space Propulsion has the goal of producing a bread-board demonstrator engine powered by LOX/LNG. In this paper the flame anchoring at the shear-coaxial injectors is investigated in function of operational load points by optical probes. The combustion chamber pressure...

The trend towards smaller satellites and mega-constellations has enormously changed the space sector and its uti-lisation in the last decades, allowing new players to enter the market and to introduce stringent requirements to enable a variety of novel applications. Alongside, also the launcher market is undergoing a transformation epoch: the devel...

Identifying the optimal design of a new launch vehicle is most important since design decisions made in the early development phase limit the vehicles' later performance and determines the associated costs. Reusing the first stage via retro-propulsive landing increases the complexity even more. Therefore, we develop an optimization framework for pa...

Nowadays, liquid rocket engines use closed-loop control at most near steady operating conditions. The control of the transient phases is traditionally performed in open-loop due to highly nonlinear system dynamics. This situation is unsatisfactory, in particular for reusable engines. The open-loop control system cannot provide optimal engine perfor...

The LUMEN project at the DLR Institute of Space Propulsion has the goal of producing a breadboard demonstrator engine powered by LOX/LNG. This paper describes the results of the first hot-fire tests of the shear coaxial injector. A preliminary analysis of the combustion stability characteristics during steady-state operating conditions is presented...

Methane is considered being a good choice as a propellant for future reusable launch systems. However, the heat transfer prediction for supercritical methane flowing in cooling channels of a regeneratively cooled combustion chamber is challenging. Because accurate heat transfer predictions are essential to design reliable and efficient cooling syst...

Porous injectors represent an alternative injection concept to coaxial injectors for rocket engine applications using gas/liquid propellant combinations such as liquid oxygen (LOX)/hydrogen (H2). This paper summarizes the main design features of porous injectors and proposes a mechanism of atomization for porous injectors that is considerably diffe...

Methane is considered being a good choice as a propellant for future reusable launch systems. However, the heat transfer prediction for supercritical methane flowing in cooling channels of a regeneratively cooled combustion chamber is challenging. Because accurate heat transfer predictions are essential to design reliable and efficient cooling syst...

API injector system has been investigated in DLR Lampoldshausen for the last decade and has been proved to be a reliable design for LOx/LH2 engines. In this work will be presented the transient models of an API injector using EcoSimPro with ESPSS library and the system evaluation in different design conditions as well as the model validation using...

Fatigue life prediction is an essential part of multidisciplinary design studies and optimization loops, but state of the art finite element based methods are numerically inefficient. We overcome this challenge by training an artificial neural network to predict the number of cycles to failure, based on combustion chamber geometry and operational p...

In recent years the scientific focus of the DLR Institute of Space Propulsion was placed on experiments related to rocket engine combustion phenomena and thrust chamber aspects. A natural extension of this scientific portfolio is the step towards engine level competence by joining the existing component level competences. The DLR project LUMEN (liq...

In the LUMEN project (liquid upper stage demonstrator engine) an expander bleed engine will be built at the DLR to allow component research on engine level. The LUMEN engine will feature two dedicated turbopumps, one for LOX and one for LNG. The turbopumps design is modular to develop sophisticated turbopump components in a representative engine cy...

This paper presents an improved design methodology for a supersonic partial admission impulse turbine for LRE, which is commonly used in open cycle applications, while focusing on the main losses from small dimension as well as the high rotational speed required for low thrust class engines as the LUMEN demonstrator engine. Also, the standard desig...

With the LUMEN (Liquid upper stage demonstrator engine) project, DLR is aiming to develop, build and operate a breadboard engine based on an expander bleed cycle scheme. The propellants for LUMEN will be liquid oxygen (LOX) and liquid methane or more specifically liquid natural gas (LNG). LUMEN will be a modular breadboard engine to be used on DLR...

The LUMEN project at the DLR Institute of Space Propulsion has the goal of producing a bread-board demonstrator engine powered by LOX/LNG. The thrust chamber of the engine features an advance porous injector (API), and a laser ignition system. This paper provides an overview of the design and functionality tests of the laser plasma ignition system....

The LUMEN project at the DLR Institute of Space Propulsion has the goal of producing a bread-board demonstrator engine powered by LOX/LNG. This paper describes the design of the baseline injection system for the LUMEN thrust chamber which uses the advance porous injector (API) concept. Numerical analysis of internal flow characteristics and acousti...

The Liquid upper stage demonstrator engine (LUMEN) to be built at the German Aerospace Center will use the expander bleed cycle. The propellants for LUMEN will be liquid oxygen (LOX) and liquid methane or more specifically liquid natural gas (LNG). The demonstrator will provide a test bed for future component development as well as to enhance the u...

Hybrid rocket engines are an interesting path towards a simple and cost-efficient way of providing thrust to a launch vehicle. Currently proposed hybrid motors mostly employ pressure-fed cycle layout to ensure low system complexity and reduced cost at the expense of performance and additional weight. While this trade is sensible for small-scale app...

This paper reports the investigation of the laser ignition of a breadboard thruster with a porous injector head. Ignition tests were performed for 80 and 980 mbar combustion chamber pressure before injection of propellants, for the two combinations LOX/H2 and LOX/CH4 and for two ignition locations. The propellant injection, the resulting flow field...

Although the utilization of Methane or Expander cycle configuration has been performed only in the close scheme, expander-bleed configuration allows a good compromise between performance and system simplicity. This paper presents the cycle analysis of a LOx/LCH4 Expander-bleed configuration for upper stage application using EcoSimPro/ESPSS, for ste...

This conference paper reports on the investigation of the laser ignition of a breadboard thruster with a porous injector head. Tests were realized for sea level and in space conditions and for the two propellant combinations LOx/H2 and LOx/CH4. A 4 step mechanism is formulated for successful ignition and flame anchoring for laser ignition of combus...

Injector behavior is of utmost importance for the performance and stability of liquid rocket engines. The injection system has to provide for a highly e�cient mixing and consequent chemical reaction of the propellants at a minimum chamber length. This article presents results of the experimental investigation for a new injection concept based on th...

This thesis deals with a novel concept for propeiiant injection in rocket engines. The Advanced Porous Injector (API) concept poses an alternative to conventional coaxial injectors for injection of gaseous/liquid propeiiant combinations (e. g. LOX/H2). The predominant mechanism of propeiiant atomization is identified through extensive experimental...

The present publication addresses the actions taken to stabilize the combustion chamber assembly using a porous injector head described in a former publication2 and the test campaign during which the success of these measures was demonstrated. The first part of this paper deals with the nature of the reported combustion instability. A phenomenologi...

A proper design of an injection system for liquid propellant rocket engines (LPRE) has to ensure a homogenous mixture of the injected propellants, which should result in a stable and highly efficient combustion process. In addition to combustion stability and efficiency it determines the propellant pressure losses upstream of the combustion chamber...

The LOX/LH2 Staged Combustion Rocket Engine Demonstrator (SCORE-D) is part of ESA’s Future Launcher Preparatory Program (FLPP). SCORE-D serves as a technology demonstrator in perspective of the development of the High Thrust Engine (HTE), which is designated as a candidate for the main stage engine of the Next Generation Launcher (NGL). To develop...

The effect of throttling on combustion efficiency and stability of a porous injector head has been investigated for the LOx/H2 propellant combination. Several pressure ramps (PR) ranging from 30 to 100 bar have been used so that a broad range of possible chamber pressures was covered. Regarding the design pressure of 80 bar, this was equivalent to...

Porous injectors operated with the cryogenic propellant combination LOX/H2 exhibit very limited sensitivity towards changes in injection conditions regarding the observed combustion performance. The interaction of the high-inertia LOX jets and the accelerating combustion gases has been identied as a possible dominating parameter of atomization. A...

Since a few years DLR Lampoldshausen has been engaged in the development of a new injection concept for cryogenic liquid propellant rocket engines. This concept bases on the injection of the liquid oxygen through a large number of simple tubes while the entire hydrogen is injected through the porous face plate.3, 4 The key feature of the API concep...