Hybrid electric engine oil tank with heat exchange capability
AssigneeRtx Corporation
InventorsJeffrey T. Morton, Murat Yazici
Life of this patent
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Abstract
An aircraft propulsion system includes a core engine that is configured to drive a propulsive fan, at least one electric machine that generates thermal energy during operation, a thermal management system that is configured to generate a lubricant flow that accepts the thermal energy generated from the at least one electric machine, an oil tank that is configured to supply and store lubricant from the thermal management system, the oil tank includes a heat exchange surface in thermal communication with a cooling flow for cooling lubricant stored within the oil tank, and a passage that is configured to direct the cooling flow to the heat exchange surface of the oil tank.
Claims21
An aircraft propulsion system comprising:
- a core engine configured to drive a propulsive fan, wherein the propulsive fan is configured to generate a bypass airflow though a bypass passage surrounding the core engine;
- at least one electric machine that generates thermal energy during operation;
- a thermal management system configured to generate a lubricant flow that accepts the thermal energy generated from the at least one electric machine and from the core engine;
- an oil tank configured to function as a lubricant reservoir that supplies and stores lubricant from the thermal management system such that a volume of lubricant remains stored within the oil tank during engine-off conditions, the oil tank comprising a heat exchange surface in thermal communication with a cooling air flow drawn from the bypass passage for convection cooling of lubricant stored within the oil tank, wherein the heat exchange surface comprises a surface area of the oil tank and the oil tank comprises a lubricant capacity, and a ratio of the surface area to the lubricant capacity is between 75 in−1 and 125 in−1;
- and
- a passage configured to direct the cooling air flow to the heat exchange surface of the oil tank without mixing with the stored lubricant.
6-8. (canceled)
A thermal management system for an aircraft propulsion system comprising:
- a lubricant circuit for a lubricant flow that accepts thermal energy from at least one electric machine;
- an oil tank configured to function as a lubricant reservoir that supplies and stores lubricant in such that a volume of lubricant remains stored within the oil tank during engine-off conditions, the oil tank comprising a heat exchange surface in thermal communication with a cooling air flow drawn from a bypass passage for cooling lubricant stored within the oil tank, wherein the heat exchange surface comprises a surface area of the oil tank and the oil tank comprises a lubricant capacity, and a ratio of the surface area to the lubricant capacity is between 75 in−1 and 125 in−1;
- and
- a passage configured to direct the cooling air flow to the heat exchange surface of the oil tank.
16-18. (canceled)
A method of operating a thermal management system for an aircraft propulsion system comprising:
- absorbing thermal energy with a lubricant flow in thermal communication with at least one electric machine coupled to a core engine structure;
- receiving a portion of a heated lubricant flow within an oil tank that functions as a lubricant reservoir that supplies and stores lubricant in such a volume that lubricant remains stored within the oil tank during engine-off conditions;
- and
- cooling lubricant within the oil tank with a cooling air flow communicated from a bypass passage over a heat exchange surface of the oil tank, wherein heat exchange surface comprises a surface area of the oil tank and the oil tank comprises a lubricant capacity, and a ratio of the surface area to the lubricant capacity is between 75 in−1 and 125 in−1.
(canceled)
Dependencies are inferred from the claim text.