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The Air Cooled Oil Cooler (ACOC) heat exchanger is an important element of the lubrication system of aero engines. The aim of the lubrication system is to cool and to lubricate the bearings and gears of the engine to ensure its proper working. The ACOC heat exchanger is complementary to another heat exchanger in the lubrication system, the Fuel Cooled Oil Cooler (FCOC) which cooles the oil by exchanging its heat to warm up the fuel before the injection. But there is a maximal temperature for fuel before the injection. Therefore an ACOC heat exchanger is placed in the system to extract the excess temperature of the oil.\\\\ The Aero-Thermo-Mechanics department of the Universit\\\'{e} libre de Bruxelles (ULB) has developed two test set-ups for the charaterisation of ACOC prototypes: a low air flow rate set-up for the experimental testing of small scale ACOC prototypes and a higher air flow rate set-up for real scales prototypes and more realistic flight conditions. The two test benches are complementary. The low air flow rate set-up is able to deliver a maximum air flow rate of 250 g/s based on a blowdown system with a 40 bar air tank \\cite{ref1}. The larger air flow facility can performed experimental campaigns on larger matrices of Additive Layers Manufacturing (ALM) ACOC prototypes. This test set-up is able to reach a maximum air mass flow rate of 700 g/s at a surpression of 1 bar. One of the particularities of the two test rigs is the control of the temperature of the air at the inlet of the ACOC heat exchanger. The air flow can be heated at a required temperature. In the test section of the air line multiple sensors are set in order to characterise the air flow at the inlet and the outlet of the prototypes. The oil circuit is similar in the two benches. It is composed of a tank, an oil heater, a pump and various sensors. The temperature of the oil can be controlled to a required value up to 200 $^\\circ$C. The objectives of the different experimental campaigns on this test rig are to measure the air pressure drop due to the ACOC heat exchanger, the thermal efficiency and the air velocity profiles at the inlet and the outlet of various prototypes for different air flow rates \\cite{ref2}. \\\\ The paper will present the two benches in more details and the different air and oil conditions that can be obtained in the benches. The oil part or the air part of the two test benches can be operated separately. |
