CFS Engineering take part in many European funded project as aerodynamic specialist to performed:
- RANS CFD calculations
- Euler CFD calculations
- Structured/Unstructured mesh generation
- FSI analysis
- Stability analysis
The RETALT (RETro propulsion Assisted Landing Technologies) project has two main scientific and technological objectives :
- To investigate the Launch system reusability technology of VTVL TSTO RLV applying
retro propulsion combined with aerodynamic control surfaces, which is currently
dominating the global market
- To investigate the Launch system reusability technology of VTVL SSTO RLV applying
retro propulsion for future spaces transportations systems
To meet the two main objectives of the project, described above, two reference configurations will be defined:
- A configuration similar to the SpaceX rocket “Falcon 9” will be the reference forstate-of-the-art TSTO RLV.
- A configuration similar to the US-American Delta Clipper will serve as reference forVTVL SSTO.
The Smart Morphing & Sensing – SMS project is a multi-disciplinary upstream project that employs intelligent electro-active actuators that will modify the lifting structure of an aircraft and to obtain the optimum shape with respect to the aerodynamic performance (high lift & low drag). This will be accomplished using a new generation of fiber optics based sensors allowing distributed pressure measurements and in-situ real-time optimisation of the aerodynamic characteristics. This will allow to attenuation of flow separation and nuisance instabilities such as aileron flutter and also to reduce trailing-edge noise and other vibration sources in flight, coming from interactions between wing and fuselage and engine or from critical meteorological phenomena as gusts, having major impact on safety.
The SMS project associates the following methods that will be coupled in a multi-disciplinary environment :
- Advanced integrated aeroelastic design using High-Fidelity CFDSM (Computational Fluid Dynamics-Structural Mechanics)
- Advanced distributed sensing using a new generation of high-fidelity fiber optics sensors
- Advanced experimental techniques to provide data together with the high-fidelity simulations for the iterative feedback of the controller design to be used for the optimisation of the morphing flap of an A320 type wing. These experimental techniques will also be used as a basis for the validation of both the novel actuation and sensing systems via wind tunnel tests at subsonic (take-off and landing) and transonic (cruise) speeds.
- Controller Design by appropriate Flight Control Commands (FCC), to actuate the electro-active materials properties in order to enable a real-time in-situ optimisation of the final prototypes in reduced scale and large scale.
- The SMS project is unique thanks to its strong multidisciplinary character and degree of innovation.
Aircraft 3rd Generation MDO for Innovative Collaboration of Heterogeneous Teams of Experts
The AGILE innovation project is granted by the European Commission. AGILE targets multidisciplinary optimization using distributed analysis frameworks. The project is set up to proof a speed up of 40% for solving realistic MDO problems compared to today’s state-of-the-art.
The use cases are realistic overall aircraft design tasks for conventional, strut-braced, box-wing and BWB configurations. The scope of development:
- Advanced optimization techniques and strategies
- Techniques for collaboration
- Knowledge-enabled information technologies
The project ran from 2015 to 2018 and was part of the Horizon 2020 program.
DLRK 2018 , Friedrichshafen, DE, 2018.
ICAS 2018 , Belo Horizonte, Brazil, 2018.
ICAS 2018 , Belo Horizonte, Brazil, 2018.
Computer-Aided Design for Aircraft Masters Thesis
EPFL - CFS Engineering, 2018.
Aircraft Engineering and Aerospace Technology, 90 (4), 2018.
Aerospace, 5 (2), 2018.
Low Speed Take-Off Aerodynamic Analysis. Conference
Paper 272 , 6th CEAS Air & Space Conference Aerospace Europe , Bucharest, Romania, 2017.
Paper 953 , 6th CEAS Air & Space Conference Aerospace Europe , Bucharest, Romania, 2017.
EPFL – CFS Engineering, 2017.
6th EASN Workshop , Porto, Portugal, 2016.
6th SCAD & READ Workshop , Warsaw, Poland, 2016.
AFLoNext was a four-year EC Level 2 project with the objective of proving and maturing highly promising flow control technologies for novel aircraft configurations to achieve a quantum leap in improving aircraft’s performance and thus reducing the environmental footprint. The project consortium was composed of forty European partners from fifteen countries. The work has been broken down into seven work packages.
The AFLoNext concept is based on six Technology Streams which cluster the targeted technologies and their associated contributions to advanced aircraft performance as follows:
- Hybrid Laminar Flow Control (HLFC) technology applied on fin and wing for friction drag reduction and thus performance increase in cruise conditions.
- Flow control technologies to enable more aggressive outer wing design for novel aircraft configurations, thereby improving the performance and the loads situation in low and high speed conditions.
- Technologies for local flow separation control applied in wing/pylon junction to improve the performance and loads situation mainly in take-off and landing conditions.
- Technologies to control the flow conditions on wing trailing edges thereby improving the performance and loads situation in the whole operational domain.
- Technologies to mitigate airframe noise during landing generated on flap and undercarriage and through mutual interaction of both.
- Technologies to mitigate/control vibrations in the undercarriage area which are caused by highly unsteady or inhomogeneous inflow conditions in take-off and landing conditions.
AFLoNext aimed to prove the engineering feasibility of the HLFC technology for drag reduction on fin in flight test and on wing by means of large scale testing. The project showed also engineering feasibility for vibrations mitigation technologies for reduced aircraft weight and noise mitigation technologies.
The peculiarity of the AFLoNext proposal in terms of holistic technical approach and efficient use of resources becomes obvious through the joint use of a flight test aircraft as common test platform for the above mentioned technologies.
To improve aircraft performance along the whole flight regime, locally applied active flow control technologies on wing and wing/pylon junction were qualified in wind tunnels or by means of lab-type demonstrators.
AIAA-2016-0803 , AIAA Scitech 2016 , San Diego, 2016.
ATAAC (Advanced Turbulence Simulation for Aerodynamic Application Challenges)
The ATAAC project aims at improvements to Computational Fluid Dynamics (CFD) methods for aerodynamic flows used in today’s aeronautical industry. The accuracy of these is limited by insufficient capabilities of the turbulence modelling / simulation approaches available, especially at the high Reynolds numbers typical of real-life flows. As LES will not be affordable for such flows in the next 4 decades, ATAAC focuses on approaches below the LES level, namely Differential Reynolds Stress Models (DRSM), advanced Unsteady RANS models (URANS), including Scale-Adaptive Simulation (SAS), Wall-Modelled LES, and different hybrid RANS-LES coupling schemes, including the latest versions of DES and Embedded LES. The resources of the project will be concentrated exclusively on flows for which the current models fail to provide sufficient accuracy, e.g. in stalled flows, high lift applications, swirling flows (delta wings, trailing vortices), buffet etc. The assessment and improvement process will follow thoroughly conceived roadmaps linking practical goals with corresponding industrial application challenges and with modelling/simulation issues through “stepping stones” represented by appropriate generic test cases
The final goals of ATAAC are:
- to recommend one or at most two “best” DRSM for conventional RANS and URANS
- to provide a small set of hybrid RANS-LES and SAS methods that can be used as “reference” turbulence-resolving approaches in future CFD design tools
- to formulate clear indications of areas of applicability and uncertainty of the proposed approaches for aerodynamic applications in industrial CFD.
Contributing to reliable industrial CFD tools, ATAAC will have a direct impact on the predictive capabilities in design and optimisation, and directly contribute to the development of Greener Aircraft.
FAST20XX (Future High-Altitude High-Speed Transport 20XX)
The current project aims at the investigation and development of technologies and steps necessary for approaches to conquer the grey zone between aeronautics and space in Europe, and thus to set the foundation of a new paradigm for transportation in the long term. The underlying concepts considered are a) a European space plane based on an airplane launch approach to advance European know how in this area, based essentially on a ballistic flight experience using hybrid propulsion, and b) the same space plane envisioned to evolve into suborbital point-to-point long-distance transport in very short times by using high-energy propulsion. An alternative, vertically starting two-stage rocket space vehicle system concept is used to identify technologies required for suborbital ultra-fast transportation. The concepts will be addressed separately and in relation to each other as well as with those considered in other EC projects, exploiting similarities and synergies wherever possible. The concepts can be classified with near term and very long term realisation capabilities, and will be evaluated according to the maturity of underlying technology, inherent risk, sustained operations, and cost. All concepts and technologies will be considered with respect to environmental issues. Some activities concern the leagal issues and those of suitable space ports. Due to the recent agreement with Virgin Galactic, it is quite natural to consider the ESRANGE facility in Sweden an excellent candidate for a starting place of experimental high-altitude high-speed flights.
Thanks to the Chimera method and 6DoF modeler available within NSMB, CFS Engineering investigated the separation of the spacecraft from its carrier aircraft by mean of unsteady simulations.
RASTAS SPEAR (RAdiation-Shapes Thermal protection investigAtionS for high-SPeed EArth Re-entry)
Strengthening of Space foundations / Research to support space science and exploration – SPA.2009.2.1.01 Space Exploration, the actions proposed on RASTAS SPEAR project try to enlarge the basic capabilities on few known topics with low Technology Readiness Level and to strengthen European Industry and Research for coming or future Space Exploration missions with focus on Sample Return Missions like Marco Polo or Mars Sample return. The project does not analyse a specific mission but deals with crucial “bricks” to be well mastered for the design of a Capsule entering in the atmosphere with high speed (more than 10 km/s).
These necessary bricks are:
1) To investigate on the available ground facilities and elaborate a proposal to improve these facilities in order to simulate in-flight conditions on ground.
2) to investigate and develop new and innovative methods, materials and systems for joining ablative blocks (tiles) together to produce a complete Thermal Protection System (TPS) for sample-return missions and validate them by tests with CIRA’s Scirocco and DLR arcjet facility.
3) to identify and test damping, energy-absorbing systems to allow survival of the Capsule Payload (collected Samples from planets…)
4) to analyse the impact of ablation (and thus Capsule shape change) on the flight mechanics.
5) to investigate and test impact of surface roughness on the heat transfer between the flow field and the capsule heat shield. The return of invest for the European Community is a European capability to design carefully a Re-entry capsule with focus on mass and thus on mission cost.
SimSAC (Simulating aircraft stability and control characteristics for use in conceptual design) was an FFP6 project running from 2006 to 2009.
Present trends in aircraft design towards augmented-stability and expanded flight envelopes call for an accurate description of the non-linear flight-dynamic behaviour of the aircraft in order to properly design the Flight Control System (FCS). Hence th e need to increase the knowledge about stability and control (S&C) as early as possible in the aircraft development process in order to be “First-Time-Right” with the FCS design architecture. FCS design usually starts near the end of the conceptual design phase when the configuration has been tentatively frozen and experimental data for predicted aerodynamic characteristics are available. Up to 80% of the lifecycle cost of an aircraft is incurred during the conceptual design phase so mistakes m ust be avoided.
To meet these challenges SimSAC develops along two major axes:
- Creation and implementation of a simulation environment, CEASIOM, for conceptual design sizing and optimisation suitably knitted for low-to-high-fidelity S&C analysis
- An improved pragmatic mix of numerical tools benchmarked against experimental data. Key objectives are: establish formalised geometry construction protocols to enable varying fidelity AeroModels, construct the CEASIOM system for S&C de sign and assessment at three levels of fidelity, including low-fidelity aero-elasticity effects, benchmark each numerical tool using established and widely recognized experimental data for existing configurations, conventional and unconventional, test and assess CEASIOM by undertaking a selection of design exercises of two types.
Achieving these objectives will advance the state-of-the-art in computer-aided concept design suitable for procuring economically amenable and ecologically friendly designs.