Session: 01-13 Thermal Management and Aero-engine Oil Systems I

Paper Number: 123819

123819 - Experimental Analysis on Performance of Air/Oil Centrifugal Breathers for Aircraft Engines Under Different Operating Conditions 

Aircraft air oil breathers are designed to decontaminate the air by efficiently removing lubricating oil droplets before venting it overboard. This will enhance the environmental sustainability of modern aircraft and reduce the oil consumption ensuring better lubrication of bearings and gearboxes. However, this will introduce pressure losses in the system directly associate to the thrust to power loss of the engine.

This paper presents an experimental investigation into the performance of centrifugal breathers designed for modern aircraft engine under a range of operating conditions. 

The experimental study explores the impact of various aspects, including the rotational speeds, the air flow rates, the particle size distribution of the droplets at the inlet of the separator, and the introduction a of coalescent media inside the breather body. 

The tests aim to evaluate the breather’s performance in removing oil droplets from the air, minimizing oil consumption, and reducing the pressure drops. 

The performance parameters identified for this study include the oil consumption, pressure losses, and particle size distribution (PSD) at the breather’s exit. The PSD is important in determining the droplet cutoff size, which is a key information for reducing the number of drops carried over by the air.

Oil consumption is measured using a gravimetric method with a filter bag. Pressure drop is monitored with a differential pressure sensor that measure the difference in the static pressure across the separator. Finally, the particle size distribution is measured with the laser diffraction technique.

The experimental results highlight significant aspect on the capabilities of air oil separators. The introduction of coalescent media shows an improvement of the separation power, however, increases the pressure drop through the separation system. An analysis of different coalescent media geometries provides further insight for optimizing the media and the breather. This analysis includes testing geometries with varying mesh sizes and different level of breather body fulfilment. By systematically changing parameters such rotational speed, air flow rate and particle size distribution for different geometries, we aim to identify improvement strategies that will contribute to the design of improved separator, that will further contribute to enhance the sustainability of aviation industry. 

Presenting Author: Mariano Di Matteo Université Libre de Bruxelles

Presenting Author Biography: Mr. Mariano Di Matteo holds a bachelor’s degree in aerospace engineering from the
University of Pisa, Italy, and a master’s degree in Electromechanical Engineering with a
specialization in Aeronautics from the Université Libre de Bruxelles. Since 2017, he has been
pursuing his Ph.D. in Engineering Science and working as a Teaching Assistant at the Aero-
Thermo-Mechanics department of the Ecole Polytechnique de Bruxelles.

Authors:

Mariano Di Matteo Université Libre de Bruxelles
Olivier Berten Univeristé Libre de Bruxelles
Patrick Hendrick Université Libre de Bruxelles