Publications de Eliott Philippe Guenat

Analysis of Spiral-Grooved Gas Journal Bearings by the Narrow-Groove Theory and the Finite Element Method At Large Eccentricities

Jürg Alexander Schiffmann, Eliott Philippe Guenat, Elia Iseli

A finite groove approach (FGA), based on the finite element method (FEM), is used for analyzing the static and dynamic behavior of spiral-grooved aerodynamic journal bearings at different eccentricities, number of grooves, and compressibility numbers. The ...

2020

Dynamic force coefficients identification on air-lubricated herringbone grooved journal bearing

Jürg Alexander Schiffmann, Eliott Philippe Guenat

The Narrow Groove Theory (NGT) is commonly used to simulate and design grooved gas bearing. However, measurements of dynamic force coefficients of Herringbone Grooved Journal Bearings (HGJBs) is missing, hence the validation historic NGT has never been per ...

2020

Advanced design methods and non-ideal gas lubrication applied to aerodynamic bearings

Eliott Philippe Guenat

Clean and energy-efficient turbomachinery are playing an increasingly important role in the decarbonization of heating systems, waste heat recovery and transportation, as the use of small-scale heat pumping and fuel cells spreads. Such machines typically e ...

EPFL2020

A Review of Grooved Dynamic Gas Bearings

Jürg Alexander Schiffmann, Eliott Philippe Guenat, Lili Gu

This paper offers an extensive review of publications dealing with the modeling, the design and the experimental investigation of grooved dynamic gas lubricated bearings. Recent years have witnessed a rise in small-scale and high-speed turbomachinery appli ...

2020

Performance potential of gas foil thrust bearings enhanced with spiral grooves

Jürg Alexander Schiffmann, Eliott Philippe Guenat

The upscaling of turbomachinery using gas foil thrust bearings is limited because of their limited load capacity and the thermal issues linked with very thin film thickness. The improvement potential of spiral grooves manufactured on the top-foil of such b ...

2019

Thin Gas Film Isothermal Condensation in Aerodynamic Bearings

Jürg Alexander Schiffmann, Eliott Philippe Guenat

High-speed small-scale turbomachinery for waste heat recovery and vapor compression cycles is typically supported on gas-lubricated bearings operating close to the saturation conditions of the lubricant. Under particular conditions, the gas film might loca ...

2019

Multi-Objective Optimization of Grooved Gas Journal Bearings for Robustness in Manufacturing Tolerances

Jürg Alexander Schiffmann, Eliott Philippe Guenat

A tolerancing method highlighting trade-offs against key design variables of mechanical systems is proposed and applied to herringbone-grooved gas journal bearings. Gas bearings typically suffer from a subsynchronous instability, demanding a very tight tol ...

2019

Multi-objective optimization of turbo-ORC systems for waste heat recovery on passenger car engines

Jürg Alexander Schiffmann, Kévin Rosset, Eliott Philippe Guenat, Violette Mounier

Waste heat recovery from passenger car internal combustion engines by means of an organic Rankine cycle (ORC) system is promising for reducing CO2 emissions. In this study, different cycle configurations capable of converting waste heat from both coolant a ...

2018

Spatially Sampled Pressure Profile Measurements in Externally Pressurized Gas Journal Bearings

Jürg Alexander Schiffmann, Eliott Philippe Guenat, Karim Magdi Zakaria Abdelrahman Shalash

Externally pressurized gas journal bearings (EPGJB) are widely adopted to support high speed rotors. This paper presents novel experimental benchmark test data which enables EPGJB model validation. Axial and circumferential pressure profile measurements ar ...

2018

Effects of humid air on aerodynamic journal bearings

Jürg Alexander Schiffmann, Eliott Philippe Guenat

The development of aerodynamic bearings applications where ambient conditions cannot be controlled (e.g., for automotive fuel cell compressor) raises the question of the effects of condensation in the humid air on perfor-mance. A modified Reynolds equation ...

2018