Research

Current Projects

Bilasurf

Full project title: Bio-Inspired Laser Functionalisation of complex 3D Industrial Surfaces

Program: Horizon Europe

Project webpage: www.bilasurf.com

Information: BILASURF aims at developing and integrating a process for high-rate laser functionalization of complex 3D surfaces using tailored designed bio inspired riblets to reduce friction and improve the environmental footprint of industrial parts | assuring a high throughput with the help of inline monitoring capabilities.

Carbo4Power

Full project title: New generation of offshore turbine blades with intelligent architectures of hybrid, nano-enabled multi-materials via advanced manufacturing

Program: Horizon 2020

Project webpage: www.carbo4power.net

Information: Carbo4Power’s main objective is to develop a new generation of lightweight, high strength, multifunctional, digitalized multi-materials for offshore turbine rotor blades that will increase their operational performance and durability while reducing the cost of energy production, maintenance, and their environmental impact.

Select

Full project title: Surface Technologies for all Electric Air Taxis

Program: Take Off

Partners: Rail Tec Arsenal Fahrzeugversuchsanlage GmbH | Peak Technology GmbH | Austrian Institute of Technology GmbH

Information: SELECT aims to develop and test surface technologies with advanced functions for ice protection and drag reduction for eVTOLs (electric vertical take-off and landing) to maintain flight safety in a wider range of icing conditions, to increase energy efficiency and performance, and to reduce noise emission of all-electric air taxis. The main subsystems that are targeted in SELECT are:(1) the passive Ice Protection System (IPS) to ensure reliable performance at low power demand, and (2) to reduce aerodynamic losses and noise emissions, maintaining high performance. The functional surface technologies will be developed targeted to the needs of the upcoming eVTOL applications.

Concluded Projects

Full project title: Riblet4Wind

Program: H2020

Project webpage: riblet4wind.eu

Information: The main objective of this project is to transfer a technology that has already demonstrated its ability to increase energy efficiency in aviation to the wind energy industry.
By applying functional coatings with a Riblet structure, the ratio of air resistance to buoyancy of the rotor blades improves considerably, which enables operation at lower wind speeds.
The turbulence behavior of the rotor blades is also improved, which enables operations even at higher wind speeds and / or less optimal wind conditions.

Contributions (see below): “Riblet-Surfaces for improvement of Efficiency of Wind Turbines”

Full title of the project: Turbulence and optical Measurements for Duct Surface Optimization in Turbofans

Program: Beyond Europe | FFG

Partners: Institut für Thermische Turbomaschinen und Maschinendynamik | GE Aviation US GE Aviation India

About: An important key component for increasing the efficiency of aircraft is the turbine transition channel between high- and low-pressure turbines. In many cases, various factors lead to poor flow quality in this area. One of the goals is therefore to gain insight into fluid physics and to characterize the development of turbulence through the canal. Together with the project partners, the potential of resistance-reducing modifications of the surfaces is examined.

Full project title: Coated riblets with antifouling effect for maritime applications

Program: Beyond Europe

Partner: MicroTau Pty Ltd | Joanneum Research Forschungsgesellschaft mbH

Kurzinformation: The project aims at a drastic reduction of hydrodynamic drag through surface modeling of bionic microstructures (so-called Riblets), the development of functional, structurable coatings and large-Riblet-structured surfaces applied on large areas. For the Calamari project, Riblet structures for maritime applications are created in a non-toxic metal-oxide-added, highly elastic paint system (= antifouling paint system) or on flexible foils. The films produced exhibit anti-fouling as well as drag-reducing functionality.

Full project titel: Large Riblet Surface with Super Hardness, Mechanical and Temperature Resistance by Nano Functionalization

Program: Horizon 2020

Project website: www.resistant-project.eu

About: ReSiSTant targets the optimization of two industrial pilot lines by using micro- and nanostructured surfaces for drag reduction. The objectives are to implement new developed surfaces into 1) Aircraft Turbofan Engines and 2) Industrial Compressors. Positive effects by usage of such surface could give benefits in terms of efficiency, CO2 reduction and noise emission and further on a positive economic and ecological impact. To enable the usage of such micro- and nanostructures, special development on the surface material for better durability in rough conditions has to be done. It is planned to do nano-functionalization, like implementing nanostructures and nanoparticles for better resistance in rough conditions.

Full project title: Inspection and Efficiency Assessment Technology

Program: Beyond Europe

Project partners: Austrian Institute of Technology GmbH – Center for Vision | Automation & Control | Graz University of Technology – Institute of Software Development | University of Wyoming – Department of Mechanical Engineering

About: The main objective of RiSPECT is to come up with the foundations behind an automated system for estimating the quality of riblet surfaces based on image data that reduces the overall costs for quality assurance measures within the riblet surface usage. Riblet defects and their impact on the aerodynamic behaviour is studied experimentally and numerically. This information is implemented into an automated optical system to detect the defects of Riblets.

Publications

Leitl, P., Flanschger, A., Rodriguez, A., Andergassen, A. (2024)
"Numerical investigation of the impact of different Riblet angles and their effect on drag reduction"
Conference: AIAA Aviation Forum And Ascend 2024
https://doi.org/10.2514/6.2024-3510

Leitl, P., Garcia de Albéniz, M., Flanschger, A., Robinson, G., Bogue, D. (2024)
"Numerical and experimental investigation of different Riblet layouts and their effect on the engine of a Stratos 716 X Business Jet"
Conference: AIAA Aviation Forum And Ascend 2024
https://doi.org/10.2514/6.2024-3509

Leitl, P., Flanschger, A., Reschenhofer, B., Gruber, R., Kurzthaler, M., Fleder, S., Lenartz, M., Neff, F., Hertz, C. (2024)
"Design and testing of Riblet film on a high-performance axial fan stage"
Conference: AIAA SciTech 2024 Forum
https://doi.org/10.2514/6.2024-1111

Garcia de Albéniz, M., Leitl, P., Flanschger, A. (2023)
"Numerical and experimental investigation of Riblet-Coating impact on centrifugal compressor stage performance"
Conference: ASME Turbo Expo 2023
https://doi.org/10.1115/GT2023-103040

Bilinsky, H.C., Quinn, M., McGrath, D., Whitelock, J., Poudyal, S., Bell, D., Leitl, P., Benauer, R., Feichtinger, Ch. (2023)
"Materials and Performance Testing of DCM Drag-Reducing Riblets for Aviation"
Conference: AIAA SCITECH 2023 Forum
http://dx.doi.org/10.2514/6.2023-1762

Flanschger, A., Heinzelmann, R., Messner, M. (2023)
„Between consultation and control: how incubators perform a governance function for entrepreneurial firms”
Accounting, Auditing & Accountability Journal. Vol. 36, 9, 86 – 107
https://www.emerald.com/insight/content/doi/10.1108/AAAJ-09-2020-4950/full/html

Kohl, D., Tsuchihashi,H., Gruber, R., Pichler, K., Goto, Y., Garcia de Albeniz, M., Naito, K., Flanschger, A., Ichinose, G. (2023)
"Numerical and experimental investigation of Riblet application on a helicopter rotor blade"
Conference: AIAA SCITECH 2023 Forum
https://doi.org/10.2514/6.2023-1765

Leitl, P., Feichtinger, Ch., Schatzdorfer, G., Flanschger, A. (2023)
"Numerical study of riblet defects and their impact on performance"
https://doi.org/2514/6.2023-1764

Leitl, P., Garcia de Albéniz, M., Smoker, J., Flanschger, A. (2023)
"Numerical and experimental investigation of different Riblet layouts on a Stratos 716 X business jet"
Conference: AIAA SCITECH 2023 Forum
https://doi.org/10.2514/6.2023-1952

Benauer, R., Schreck, St., Leitl, P., Badžek, E., Patinios, M., Farisco, F. (2022)
"A Numerical Study on the Effects of Circumferential Positions of Combustor Hot Streaks on a TCF Configuration"
https://doi.org/10.1115/GT2022-82419

Garcia de Albeniz Martinez, M.L., Leitl, P., Costa, D., Flanschger, A. Forster, B. (2022)
"Numerical Investigation and Application of Riblets within the Safety Analysis and following Execution of the stunt Tunnel Flight"
Conference: AIAA AVIATION 2022 Forum
https://doi.org/10.2514/6.2022-3664

Leitl, P., Flanschger, A., Garcia de Albéniz, M., Rodriguez, A., Pereira, A., Forster, B. (2022)
"Investigation of the impact of different Riblet layouts on a long- and medium-range Aircraft model"
AIAA 2022-0919, Special Session: Drag-Reducing Surfaces I.
https://doi.org/10.2514/6.2022-0919

Leitl, P., Flanschger, A., Ortiz de Viñaspre, I., Pereira, A. (2022)
"Investigation of the impact of different riblet technologies and its application on a Boeing 777 airplane model"
Conference: AIAA SCITECH 2022 Forum
https://doi.org/10.2514/6.2022-0919

Leitl, P., Shiraishi, M. Flanschger, A., Tsuchihashi, S., Marn, A., Schreck, St., Ichinose, G., Shibazaki, Y., Benauer, R. Pramstrahler, S. (2022)
"Numerical and Experimental Investigation of Lasered Riblets on Turbine Exit Guide Vanes and the Impact on the Performance"
Conference: AIAA SCITECH 2022 Forum
https://doi.org/10.2514/6.2022-0917

Leitl, P., Feichtinger, Ch., Wotawa, F., Naughton, J. (2022)
"Measurements of macroscopic and microscopic Riblet defects and their impact on performance"
Conference: AIAA SCITECH 2022 Forum
https://doi.org/10.2514/6.2022-0916

Pramstrahler, S., Peters, A., Garcia de Albéniz, M.L., Leitl, P.A., Heitmeir, F. Marn, A. (2022)
"The Impact of Inlet Flow Angle on Turbine Vane Frame Aerodynamic Performance"
Conference: ASME Turbo Expo 2022: Turbomachinery Technical Conference and Exposition
https://doi.org/10.1115/GT2022-78065

Quinn, M., McGrath, D., Bell, D., Bilinsky, H., Builth-Williams, J., Feichtinger, Ch., Leitl, P.A., Flanschger, A., Shahjahan, S. (2022)
"Advancements in Drag-Reducing Riblet Film Production for Aviation and Other Applications"
Conference: AIAA SCITECH 2022 Forum
https://doi.org/10.2514/6.2022-0920

Leitl, P.A., Feichtinger, Ch., Bilinsky, H., Flanschger, A., Quinn, M., Ortiz de Viñaspre, I., Forster, B. (2021)
"Riblet design, manufacturing, and measurements – A new rapid iteration process"
Conference: AIAA Scitech 2021 Forum
https://doi.org/10.2514/6.2021-0036

Leitl, P., Feichtinger, Ch., Kowalik, Y., Reschenhofer, B., Merli, F., Brinkmann, A., Flanschger, A., Göttlich, E., Stenzel, V. Marn, A. (2021)
"Performance improvement of Riblets in a Turbine Center Frame and their material development for high temperature environments"
Project: TURANDOT - Turbulence and Optical Measurements for Duct Surface Optimization in Turbofans, Conference: AIAA Scitech 2021 Forum
https://doi.org/10.2514/6.2021-0033

Leitl, P., Feichtinger, Ch., Naughton, J., Flanschger, A., Husen, N., Ortiz de Viñaspre, I., Mier, F., Forster, A. (2021)
"Measurement of riblet defects and their impact on performance"
Conference: AIAA Scitech 2021 Forum
https://doi.org/10.2514/6.2021-0034

Leitl, P.A., Flanschger, A., Garcia de Albéniz, M., Piscitelli, G., Ferrante, E., Costa, E. (2021)
"Riblet Surfaces for Performance Increase in Aircraft Turbines"
Conference: 2021 12th International Conference on Mechanical and Aerospace Engineering (ICMAE)
https://doi.org/10.1109/ICMAE52228.2021.9522394

Leitl, P.A., Feichtinger, Ch., Flanschger, A., Ortiz de Viñaspre, I., Forster, A., Naughton, J.W., Husen, N., Mier F.A. (2021)
"Measurement of riblet defects and their impact on performance"
AIAA Paper 2021- 0119
https://doi.org/10.2514/6.2021-0034

Leitl, P.A., Göttlich, E., Flanschger, A., Peters, A., Feichtinger, Ch.,Marn, A., Reschenhofer, B. (2020)
"Numerical investigation of optimal riblet size for turbine center frame strut flow and their impact on performance"
Session: Special Session: Engineered Surfaces, Materials, and Coatings for Viscous Drag Reduction AIAA 2020-0307
https://doi.org/10.2514/6.2020-0307

Leitl, P.A., Stenzel, V., Flanschger, A., Kordy, H., Feichtinger, Ch. Kowalik, Y., Schreck, St., Stübing, D., (2020)
"Riblet Surfaces for Improvement of Efficiency of Wind Turbines"
Conference: AIAA Scitech 2020 Forum
https://doi.org/10.2514/6.2020-0308

Leitl, P.A., Göttlich, E., Flanschger, A., Peters, A., Feichtinger, Ch., Marn, A., Reschenhofer, B. (2020)
"Numerical investigation of optimal riblet size for TCF strut flow and their impact on the performance"
AIAA paper 2020-0307, Jan. 2020
https://doi.org/10.2514/6.2020-0307

Schreck, St. (2020)
"Influence of the circumferential position of combustor hot streaks onto the performance of a TCF"
Masterarbeit Graz: Institute of Thermal Turbomachinery and Machine Dynamics

AIAA Scitech Forum and Exposition 2020
“Numerical investigation of optimal Riblet size for TCF strut flow and their impact on performance” – Florida, 2020

AIAA Scitech Forum and Exposition 2020
“Riblet surfaces for improvement of Efficiency of Wind turbines” – Florida, 2020

Benauer, R., Fraundorfer, F., Leitl, P., Mohr, L. (2019)
"Damage Estimation of Explosions in Urban Environment by Simulation"
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XLII-3/W8, Gi4DM International Conference
https://doi.org/10.5194/isprs-archives-XLII-3-W8-253-2019

Costa, E., Garcia de Albéniz, M., Barberis, St., Leitl, P. (2019)
"Increase of Compressor Performance through the Use of Microstructures"
SAE Technical Paper 2019-24-0239, Conference: Conference on Sustainable Mobility
https://doi.org/10.4271/2019-24-0239

Costa, E., Piscitelli, G., Ferrante, E., Leitl, P., Flanschger, A., Garcia de Albéniz, M.L. (2019)
"Incremento delle prestazioni di un compressore mediante microstrutture"
A&C Análisis & Calcolo, N. 94, 56-62
https://aec-analisiecalcolo.it/pubblicazioni/aec/94/incremento-delle-prestazioni-di-un-compressore-med

Leitl, P., Garcia de Albéniz, M.L., Flanschger, A. (2019)
"Increase of Compressor Performance through the Use of Microstructures"
SUPEHR 19
https://doi.org/10.4271/2019-24-0239

Leitl, P.A., Kuntzagk, St., Flanschger, A., Pfingsten, K. (2019)
"Experimental and numerical investigation of the reduction in skin friction due to riblets applied on the surface of a Taylor-Couette cell"
AIAA SciTech Forum and Exposition 2019-1625
https://doi.org/10.2514/6.2019-1625

Hafizovic, A., Heitmeir, F., Leitl, P., Marn, A., Simonassi, L., Zenz, M. (2019)
"Aeroacoustical and Aerodynamical investigations of Riblets applied on low pressure turbine exit guide vanes for two different operating points"
ASME Turbo Expo: Turbomachinery Technical Conference and Exposition (GT)
https://doi.org/10.1115/GT2019-90283

Leitl, P.A., Garcia de Albéniz, M.L., Flanschger, A. (2019)
"Nano- and microstructured Riblet surfaces for centrifugal industrial compressors"
Sustainable PolyeEnergy generation and Harvesting: Conference Proceedings, 32-38, Genova: University Press
https://doi.org/10.1400/274691.4610256

Mohr, L., Leitl, P., Fraundorfer, F. (2019)
"Damage Estimation of Explosions in Urban Environments by Simulation"
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information, Vol 42, 3/W8, 253-260
https://doi.org/10.5194/isprs-archives-XLII-3-W8-253-2019

Neumann M., Machado Charry E., Leitl P.A., Hirn U., Zojer K., Schmidt, V. (2019)
"Joint distribution of local porosity and local tortuosity in sack paper"
Proceedings of the international paper physics conference. TAPPI, Indianapolis, 100–105

Reschenhofer, B. (2019)
"Numerical Investigation of the Impact of Riblets on Turbine Center Frames"
Diplomarbeit. Graz: Institute of Thermal Turbomachinery and Machine Dynamics.
https://online.tugraz.at/tug_online/wbabs.showThesis?pThesisNr=68321&pOrgNr=37

Zenz, M., Hafizovic, A., Simonassi, L., Leitl, P.A., Benauer, R., Heitmeir, F., Marn, A. (2019)
"Aerodynamical and aeroelastic investigations of a riblet design applied on the surface of turbine exit guide vanes of a low pressure turbine"
13th European Conference on Turbomachinery Fluid dynamics & Thermodynamics, 55.
https://doi.org/10.29008/ETC2019-055

Zenz, M., Hafizovic, A., Simonassi, L., Leitl, P.A., Heitmeir, F., Marn, A. (2019)
"Aeroacoustical and Aerodynamical Investigations of Riblets Applied on Low Pressure Turbine Exit Guide Vanes for Two Different Operating Points"
Proceedings of the ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition, Vol. 2B, V02BT43A001, Phoenix: Arizona.
https://doi.org/10.1115/GT2019-90283

Simonassi, L., Benauer, R., Zenz, M., Leitl, P., Heitmeir, F., Marn A. (2019)
"Numerical and experimental study of the aerodynamic and aeroelastic performance of a low pressure turbine"
European Conference on Turbomachinery Fluid Dynamics and Thermodynamics
https://doi.org/10.29008/ETC2019-056

SUPEHR 2019
“Nano- & Microstructured Riblet surfaces for centrifugal industrial compressors” – Savona, 2019

AIAA SciTech Forum and Exposition 2019
“Experimental and numerical investigation of the reduction in skin friction due to Riblets applied on the surface of a Taylor Couette cell” – Kalifornien, 2019

IntAIRCoat 2019
“Testbench for Riblet Surfaces in Aviation – Experimental and numerical investigation of the reduction in skin friction due to Riblets applied on the surface of a Taylor-Couette cell” – Hamburg, 2019

Bader, P., Leitl, P., Sanz, W., Steinmayr, Ch. (2017)
"The capability of large eddy simulation to predict relaminarization"
International Journal of Heat and Fluid Flow, Vol. 68, 364-372.
https://doi.org/10.1016/j.ijheatfluidflow.2017.09.008

Benauer, R. (2017)
"Numerische Simulation der Schallentstehung und Ausbreitung in modernen Zweikreistriebwerken"
Masterarbeit. Graz: Technische Universität, Institut für Thermische Turbomaschinen und Maschinendynamik.
https://online.tugraz.at/tug_online/wbAbs.showThesis?pThesisNr=62109&pOrgNr=2298

"The capability of large eddy simulation to predict ralaminarization”
International Journal of Head and Fluid Flow, 2017

Bader, P., Sanz, W., Steinmayr, C., Leit. A. (2016)
"Comparison of RANS and Embedded LES Calculations with Measurements of Transitional Flow Along a Flat Plate"
ERCOFTAC Bulletin 2016, JG 106, 03, 84-91
https://www.ercoftac.org/downloads/bulletin-docs/ercoftac_bulletin_106.pdf

Steinmayr, Ch. (2016)
"3D-Simulation von Transition und Relaminarisierung entlang einer ebenen Platte"
Institut für thermische Turbomaschinen und Maschinendynamik, Masterarbeit. Graz. Technische Universität.
https://diglib.tugraz.at/3d-simulation-von-transition-und-relaminarisierung-entlang-einer-ebenen-platte-2016

“3D LES Simulation zur Akustikberechnung von überkritischen Ventilen in Resonanz”
ANSYS Conference & 10. Austrian CDFEM Users’ Meeting 2015

Leitl, P.A. (2015)
"3D LES Simulation zur Akustikberechnung von überkritischen Ventilen in Resonanz"
ANSYS Conference & 10. Austrian CDFEM Users’ Meeting 2015

P. Bader, P Leitl, W. Sanz, C. Steinmayr (2015)
"RANS and eLES Simulations of Relaminarization"

4. VDI Fachkonferenz, Rotor und Rotorblätter von Windenergieanlagen
“Ist die Steigerung der Effizienz von WEA durch strömungsoptimierte Beschichtung möglich” – Bremen, 2014

10. Werkstoffkongress, Next Generation of Materials and Devices from Bioinspiration
“Flow optimization by microstructured surfaces – identification of opportunities and requirements” – Leoben, 2013

OPEN MATERIALS
“Funktionalität, Nutzen und Anwendung von Mikro- und nanostrukturierten Oberflächen zur Reibungsverminderung” – Leoben, 2013

Fachtagung “HAI-TECH”, Bundesministerium für Wirtschaft und Technologie
“Riblets – Praktische Anwendungen und Möglichkeiten” -Berlin, 2012

“CFD-Simulation eines H-Rotors mit variablem Pitchwinkel”
ANSYS Conference & 30. CADFEM Users’ Meeting 2012

Flanschger, A. (2012)
"Controlling in technologiebasierten Jungunternehmen." Bauer, U. (Hrsg.)
Monographic series. Verlag der Technischen Universität Graz

Flanschger, A. (2012)
"Mitbewerberanalyse in der Faserverbundindustrie Europas"
Masterarbeit. Graz: Technische Universität, Institut für Betriebswirtschaftslehre und Betriebssoziologie

Flanschger, A. (2012)
"Controlling von technologiebasierten Jungunternehmen unter spezieller Berücksichtigung der Rolle des Inkubators"
Dissertation. Graz: Technische Universität, Institut für Betriebswirtschaftslehre und Betriebssoziologie

Leitl, P.A., Flanschger, A. (2011)
"Flow optimization by microstructured surfaces in the railway industry"
Identification of opportunities and requirements for high-speed trains
https://www.researchgate.net/publication/295424845_Flow_optimization_by_microstructured_surfaces_in_the_railway_industry_identification_of_opportunities_and_requirements_for_high-speed_trains

Leitl, P.A., Sanz, W., Heitmeir, F. (2011)
“Design and CFD simulation of a booster compressor with volute”
The 9th European Conference on Turbomachinery Fluid Dynamics and Thermodynamics

40th Conference on Modern Rolling Stock
“Strömungsoptimierung durch mikrostrukturierte Oberflächen im Eisenbahnwesen, Darstellung von Möglichkeiten und Anforderungen bei Hochgeschwindigkeitszügen” – Graz, 2011

Nano and Photonics 2011
“Development and Usage of micro- and nanostructured bionic surfaces” – Mauterndorf, 2011

Salzburger Dialoge 2011 zur Biokommunikation
“Laminare und turbulente Strömungssysteme. Flow und Chaos” – Salzburg, 2011

4. Weizer Nano Business Talk
“Herstellung und Anwendung von mikro- und nanostrukturierten bionischen Oberflächen – Möglichkeiten und Herausforderungen” – Weiz, 2010

Leitl, P.A. (1997)
"Time Resolved Investigation of Unsteady Flow Inside Inlet Manifolds and Characterization of Inlet Flow Behavior"
Technical Paper 97 2828, SAE International in United States
https://doi.org/10.4271/972828

Research

Current Projects

Bilasurf

Carbo4Power

Select

Concluded Projects

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