Retro Propulsion Assisted Landing Technologies (RETALT): Current Status and Outlook of the EU Funded Project on Reusable Launch Vehicles

Ansgar, Marwege,; Klevanski, Josef; Riehmer, Johannes; Kirchheck, Daniel; Karl, Sebastian; Bonetti, Davide; Vos, Jan B.; Jevons, M.; Krammer, Anett; Carvalho, João Andrade de

doi:10.5281/zenodo.5770046

Cited by 2 publications

(7 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 11 shows the Mach numbers selected for the wind tunnel tests at DLR in Cologne, mapped onto the reference trajectory presented in [9]. As mentioned in the introduction, the tests performed in the H2K rebuild the hypersonic part of the retro propulsion maneuver during the re-entry burn.…”

Section: Test Conditionsmentioning

confidence: 99%

“…In this environment of European research in this field, the RETALT (RETro propulsion Assisted Landing Technologies) project is funded in the frame of the Horizon 2020 framework program (grant agreement No 821890) and is investigating key technologies for the descend and vertical landing of launcher configurations with the aid of retro propulsion, where the engines are firing against the flight velocity vector. The project was summarized in [9]. Marwege et Two reference configurations are being studied in the project which are:…”

mentioning

confidence: 99%

“…Fig.11Mapping of Mach numbers tested in the wind tunnel facilities over the reference trajectory presented in[9] …”

mentioning

confidence: 99%

See 2 more Smart Citations

Hypersonic retro propulsion for reusable launch vehicles tested in the H2K wind tunnel

Ansgar¹,

Kirchheck²,

Klevanski³

et al. 2022

CEAS Space J

Self Cite

View full text Add to dashboard Cite

In the frame of the RETALT (RETro propulsion Assisted Landing Technologies) project, the aerodynamics of reusable launch vehicles reentering the atmosphere and descending and landing with the aid of retro propulsion are studied. In particular, series of wind tunnel tests are performed to assess the aerodynamic properties of such a vehicle in the various flight phases from hypersonic and supersonic re-entry down to subsonic conditions at touch down. This paper discusses the results of wind tunnel tests in the Hypersonic Wind Tunnel Cologne (H2K) at the Supersonic and Hypersonic Flow Technologies Department of the German Aerospace Center (DLR) in Cologne for the hypersonic retro propulsion maneuver during the re-entry burn. Mach numbers of 5.3 and 7.0 were tested with a variation of thrust coefficient, Reynolds number, angle of attack, cold and heated air. A single-engine configuration and a configuration with three active engines were tested. In all tests, the engine exhaust was simulated using ambient temperature or heated air. Dependencies of the flow features of the square root of the thrust coefficient known from literature for the single-engine case can be confirmed and extended to the three-engine configuration. For the single-engine case, the formation of vortex rings was observed, which eventually leads to strong individual vortices and extensive flow field disturbances. The heating of the supply air up to 600 K mitigates condensation in the retro plume, while the overall flow structures remained unchanged. High thrust coefficients generally lead to vanishing pressure coefficients on the engine bay. The single and the three-engine cases are comparable in this sense. The Mach number and Reynolds number are of subordinate importance for the pressures on the vehicle, while the thrust coefficient is the dominating similarity parameter. Pressure coefficients far downstream of the retro plume are affected less and, therefore, are not negligible at non-zero angles of attack. In this paper, the methodology of the wind tunnel tests and the results obtained are described in detail.

show abstract

Section: Test Conditionsmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Hypersonic retro propulsion for reusable launch vehicles tested in the H2K wind tunnel

Ansgar¹,

Kirchheck²,

Klevanski³

et al. 2022

CEAS Space J

Self Cite

View full text Add to dashboard Cite

show abstract

“…The successful retro-propulsive landing of the first stage of the Falcon 9 heavy lift launcher in 2015 and the successive application of this method in its operations, resulted in that vertical landing with the aid of retro propulsion can be considered to be state-of-the art in the USA. This created large interest in Europe, which resulted in the RETALT (Retro Propulsion Assisted Landing Technologies) project which was funded by the European Union in the frame of the Horizon 2020 framework program under the grant agreement No 821890, to study key technologies identified for retropropulsive descent and landing (Marwege et al 2022a, Marwege et al 2019). One of the main goals of the project was to create a foundation for the understanding of the complex unsteady aerodynamics for such vehicles during the descent and landing approach.…”

Section: Introductionmentioning

confidence: 99%

“…Mach numbers tested in the wind tunnel facilities at DLR in Cologne are mapped on the reference trajectory presented in(Marwege et al 2019). In addition to the tests performed in the VMK, which are part of this paper, also the Mach numbers tested in the Trisonic Wind Tunnel Cologne (TMK)(Marwege et al 2022b, Marwege et al 2022c) and in the Hypersonic Wind Tunnel Cologne (H2K) Gülhan 2023, Marwege et al 2022d) are included.…”

mentioning

confidence: 99%

Aerodynamic Characteristics of the Retro Propulsion Landing Burn of Vertically Landing Launchers

Marwege,

Gülhan

2023

Preprint

View full text Add to dashboard Cite

In the frame of the European funded H2020 project RETALT (Retro Propulsion Assisted Landing Technologies) the unsteady aerodynamics of vertically descending and landing launchers have been investigated. In this paper experimental data of the landing burn tested in the Vertical Free-Jet Facility Cologne (VMK) at DLR in Cologne is presented. The landing burn was simulated with a cold gas jet of pressurized air opposing the wind tunnel free stream. Tests with several jet conditions were compared to results without active jet. Proper Orthogonal Decomposition of Schlieren recordings and spectral analyses of their time histories are performed and are compared to frequencies in pressure measurements. Dominant frequencies were found, which are strongest at Mach 0.8. Especially a Strouhal number of 0.2 was found to be most dominant. The intensity of the dominant frequencies, can be lowered if the engine is active. The normalized root mean square pressure fluctuations are between 0.1 and 0.3 during the landing maneuver. Additionally, the steady flow features scale well with the ambient pressure ratio and the momentum flux ratio.

show abstract

Retro Propulsion Assisted Landing Technologies (RETALT): Current Status and Outlook of the EU Funded Project on Reusable Launch Vehicles

Cited by 2 publications

References 0 publications

Hypersonic retro propulsion for reusable launch vehicles tested in the H2K wind tunnel

Hypersonic retro propulsion for reusable launch vehicles tested in the H2K wind tunnel

Aerodynamic Characteristics of the Retro Propulsion Landing Burn of Vertically Landing Launchers

Contact Info

Product

Resources

About