Publications associées à Aircraft engine

Smart Acoustic Lining for UHBR Technologies Engine Part 1: Design of an Electroacoustic Liner and Experimental Characterization Under Flow in Rectangular Cross-Section Ducts

The new generation of Ultra-High-By-Pass-Ratio (UHBR) turbofan engine while considerably reducing fuel consumption, threatens higher noise levels at low frequencies because of its larger diameter, lower number of blades and rotational speed. This is accomp ...

American Institute of Aeronautics and Astronautics2024

Domain adaptation via alignment of operation profile for Remaining Useful Lifetime prediction

Olga Fink, Ismail Nejjar, Mengjie Zhao

Effective Prognostics and Health Management (PHM) relies on accurate prediction of the Remaining Useful Life (RUL). Data-driven RUL prediction techniques rely heavily on the representativeness of the available time-to-failure trajectories. Therefore, these ...

2024

The Advection Boundary Law in presence of mean-flow and spinning modes

In the attempt to reduce fuel consumption, a new generation of Ultra-High-By-Pass-Ratio (UHBR) turbofans have been introduced in the aeronautic industry which are structurally noisier especially at lower frequencies, because of their larger diameter, lower ...

SPIE2024

Robust tunable acoustic impedance control on electroacoustic resonators for aircraft noise reduction

Maxime Volery

Air traffic noise emissions are responsible for a significant part of the overall environmental noise, especially in the vicinity of airports. Exposure to environmental noise is known to negatively impact health and to be associated with cardiovascular dis ...

EPFL2023

Indication of 310-Helix Structure in Gas-Phase Neutral Pentaalanine

Vasyl Yatsyna

We investigate the gas-phase structure of the neutral pentaalanine peptide. The IR spectrum in the 340-1820 cm-1 frequency range is obtained by employing supersonic jet cooling, infrared multiphoton dissociation, and vacuum-ultraviolet action spectroscopy. ...

AMER CHEMICAL SOC2023

Uncertainty quantification in machine learning for engineering design and health prognostics: A tutorial

Olga Fink, Luca Biggio

On top of machine learning (ML) models, uncertainty quantification (UQ) functions as an essential layer of safety assurance that could lead to more principled decision making by enabling sound risk assessment and management. The safety and reliability impr ...

2023

Sharp turning maneuvers with avian-inspired wing and tail morphing

Dario Floreano, Valentin Wüest, Enrico Ajanic, Mir Alikhan Bin Mohammad Feroskhan

Flight in dense environments, such as forests and cities requires drones to perform sharp turns. Although fixed-wing drones are aerodynamically and energetically more efficient than multicopters, they require a comparatively larger area to turn and thus ar ...

2022

Real-time model calibration with deep reinforcement learning

Olga Fink

The real-time, and accurate inference of model parameters is of great importance in many scientific and engineering disciplines that use computational models (such as a digital twin) for the analysis and prediction of complex physical processes. However, f ...

2022

A Morphing Cargo Drone for Safe Flight in Proximity of Humans

Dario Floreano, Przemyslaw Mariusz Kornatowski, William John Stewart, Mir Alikhan Bin Mohammad Feroskhan

Delivery drones used by logistics companies today are equipped with unshielded propellers, which represent a major hurdle for in-hand parcel delivery. The exposed propeller blades are hazardous to unsuspecting bystanders, pets, and untrained users. One sol ...

2020

Low-loss SiN waveguides for efficient and broadly tunable nonlinear frequency conversion

Tobias Kippenberg, Camille Sophie Brès, Junqiu Liu, Florent Gilles Mazeas

We report on the use of low-loss Si3N4 waveguides for efficient frequency conversion tunable from the near infrared to the short-wave infrared. We achieve -15 dB conversion efficiency for 200 mW coupled pump power. ...

2020

Theoretical and Experimental Investigation of a 34 Watt Radial-Inflow Steam Turbine with Partial-Admission

Jan Van Herle, Jürg Alexander Schiffmann, Patrick Hubert Wagner

A micro steam turbine with a tip diameter of 15 mm was designed and experimentally characterized. At the nominal mass flow rate and total-to-total pressure ratio of 2.3 kg/h and 2, respectively, the turbine yields a power of 34 W and a total-to-static isen ...

2021

Theoretical and Experimental Investigation of a 34 Watt Radial-Inflow Steam Turbine with Partial-Admission

Jan Van Herle, Jürg Alexander Schiffmann, Patrick Hubert Wagner

A micro steam turbine with a tip diameter of 15mm was designed and experimentally characterized. At the nominal mass flow rate and total-to-total pressure ratio of 2.3 kgh-1 and 2, respectively, the turbine yields a power of 34W and a total-to-static isent ...

2021

Mitigation of tip leakage induced phenomena in a low Reynolds number centrifugal compressor via blade loading distribution

Markus Diehl

Reduced-scale refrigeration compressors supported on gas-lubricated bearings have been identified as a key technology for domestic heat pump applications, in order to improve both the system efficiency and the reliability. Unfortunately, reduced-scale mach ...

EPFL2019

An origami-inspired cargo drone

Dario Floreano, Stefano Mintchev, Przemyslaw Mariusz Kornatowski

Multicopters stand to revolutionize parcel delivery because of their capability to operate in areas with unsuitable road infrastructure and precisely maneuver in cluttered environments. However, current multicopters for delivery can be dangerous for people ...

2017

Design, modeling and experimental validation of a novel finned reciprocating compressor for Isothermal Compressed Air Energy Storage applications

Alfred Rufer, Mahbod Heidari

Considering the need for a reliable and environmentally friendly energy storage solution for addressing renewable energy intermittency issue and following the developments on Isothermal Compressed Air Energy Storage (I-CAES) systems, a new finned piston co ...

Pergamon-Elsevier Science Ltd2017

Design and experimental validation of an active acoustic liner for aircraft engine noise reduction

Hervé Lissek, Romain Boulandet, Sami Driss Karkar, Gaël Matten

The use of acoustic liners in aviation industry is a quite common solution for reducing the engines acoustic emissions. Although the current solutions based on single or multilayer liners are efficient and compact for the mid and high frequencies, noise mi ...

2017

A new ring‐shaped wind tunnel facility to study wind‐packing of snow

Michael Lehning, Christian Gabriel Sommer, Charles Fierz

A new wind tunnel was designed and built at SLF. The facility is ring-shaped to simulate an infinite fetch. This is important for experiments where the observed processes have a slow time scale (minutes to hours). The wind tunnel was developed to study the ...

University de Genève2016

Experimental investigation of a two-stage oil-free domestic Air/Water heat pump prototype powered by an oil-free high-speed twin-stage radial compressor rotating on gas bearings

Daniel Favrat, Jürg Alexander Schiffmann, Jean-Baptiste Carré

Domestic heat pumps have been identified as a key-technology to decrease the energy consumption of the domestic sector, which represents 29% of the world final energy consumption. Space & water heating represent more than two third of the domestic sector e ...

2016

Experimental characterization of a five blade tubular propeller turbine for pipe inline installation

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Vlad Hasmatuchi, Irene Almeida Samora, Cécile Münch-Alligné

The interest in micro-hydropower in existing infrastructure is increasing since this is a technology with low environmental impacts and potential for energy recovery in different types of installation. The technologies available for these schemes are still ...

Elsevier2016

Effect of Varying Jet Diameter on the Heat Transfer Distributions of Narrow Impingement Channels

Peter Ott, Alexandros Terzis, Bernhard Weigand

The development of integrally cast turbine airfoils allows the production of narrow impingement channels in a double-wall configuration, where the coolant is practically injected within the wall of the airfoil providing increased heat transfer capabilities ...

Asme2015