Gearbox assembly with lubricant extraction volume ratio

A gas turbine engine comprising:

• a fan having a fan shaft;
• a compressor section, a combustion section, and a turbine section, the turbine section having a low-pressure shaft drivingly coupled to the compressor section;
• a gearbox assembly, the fan shaft coupled to the low-pressure shaft through the gearbox assembly, wherein the gearbox assembly comprises:
• a gearbox having a gearbox volume defined by an outer diameter of the gearbox and a gearbox length of the gearbox;
• and
• a gutter for collecting a gearbox lubricant scavenge flow from the gearbox, the gutter having a gutter volume defined by an inner surface of a gutter wall of the gutter and being characterized by a lubricant extraction volume ratio between 0.01 and 0.3, inclusive of the endpoints, for a maximum gearbox power greater than 35 kHP and less than or equal to 90 kHP, and the lubrication extraction volume ratio is between 0.03 to 0.3, inclusive of the endpoints, for a maximum gearbox power less than 35 kHP, the lubricant extraction volume ratio defined by:
• V
• G
• V
• GB
• ,
• wherein VG is the gutter volume of the gutter and VGB is the gearbox volume;
• and
• a lubrication system comprising:
• a tank that stores a lubricant therein;
• one or more lubricant pumps for generating a flow of lubricant from the tank to the gearbox assembly;
• a flow rate control valve in fluid communication with the flow of lubricant and defining a flow inlet and a flow outlet, the flow rate control valve defining a variable throughput from the flow inlet to the flow outlet for controlling a flowrate of the lubricant to the gearbox assembly;
• and
• a gearbox lubricant heat exchanger positioned in thermal communication with the flow of lubricant generated by the one or more lubricant pumps at a location downstream of the flow rate control valve for controlling a temperature of the lubricant to the gearbox assembly.