A generator arranged to be driven by an aircraft engine, the generator comprising: a rotor, comprising: a rotor inlet for receiving a fluid; a plurality of outlets (104a-d) configured to release the fluid from a radially outer region of the rotor; and a fluid distribution arrangement arranged to direct fluid from the rotor inlet to one or more of the plurality of outlets (104a-d), wherein the fluid distribution arrangement comprises a cavity at a first end of the rotor for receiving fluid from the rotor inlet, and a plurality of inlet openings (212, 214) within the cavity for directing fluid to the plurality of outlets (104a-d) via respective fluid paths (208, 210); wherein the fluid distribution arrangement is configured to selectively distribute fluid to the plurality of outlets (104a-d) in dependence on an operational parameter of the rotor, wherein fluid is distributed to a first subset of the plurality of outlets (104a-b) via a first set of inlet openings within the cavity when the operational parameter is above a first threshold value, wherein fluid is further distributed to a second subset of the plurality of outlets (104c-d) via a second set of inlet openings within the cavity when the operational parameter is below the first threshold value, and wherein the first subset of the plurality of outlets (104a-b) are arranged at different circumferential positions on the rotor to the second subset of the plurality of outlets (104c-d); and the generator further comprising a restrictor configured to provide a constant flow rate of fluid at the rotor inlet, independent of a velocity at which the rotor is rotating, wherein the constant flow rate of fluid received at the rotor inlet is divided between the first subset of the plurality of outlets (104a-b), or the first and second subset of the plurality of outlets (104a-b), such that the velocity at which the fluid is released from the plurality of outlets (104a-d) varies with the operational parameter. a rotor, comprising: a rotor inlet for receiving a fluid; a plurality of outlets (104a-d) configured to release the fluid from a radially outer region of the rotor; and a fluid distribution arrangement arranged to direct fluid from the rotor inlet to one or more of the plurality of outlets (104a-d), wherein the fluid distribution arrangement comprises a cavity at a first end of the rotor for receiving fluid from the rotor inlet, and a plurality of inlet openings (212, 214) within the cavity for directing fluid to the plurality of outlets (104a-d) via respective fluid paths (208, 210); wherein the fluid distribution arrangement is configured to selectively distribute fluid to the plurality of outlets (104a-d) in dependence on an operational parameter of the rotor, wherein fluid is distributed to a first subset of the plurality of outlets (104a-b) via a first set of inlet openings within the cavity when the operational parameter is above a first threshold value, wherein fluid is further distributed to a second subset of the plurality of outlets (104c-d) via a second set of inlet openings within the cavity when the operational parameter is below the first threshold value, and wherein the first subset of the plurality of outlets (104a-b) are arranged at different circumferential positions on the rotor to the second subset of the plurality of outlets (104c-d); and a rotor inlet for receiving a fluid; a plurality of outlets (104a-d) configured to release the fluid from a radially outer region of the rotor; and a fluid distribution arrangement arranged to direct fluid from the rotor inlet to one or more of the plurality of outlets (104a-d), wherein the fluid distribution arrangement comprises a cavity at a first end of the rotor for receiving fluid from the rotor inlet, and a plurality of inlet openings (212, 214) within the cavity for directing fluid to the plurality of outlets (104a-d) via respective fluid paths (208, 210); wherein the fluid distribution arrangement is configured to selectively distribute fluid to the plurality of outlets (104a-d) in dependence on an operational parameter of the rotor, wherein fluid is distributed to a first subset of the plurality of outlets (104a-b) via a first set of inlet openings within the cavity when the operational parameter is above a first threshold value, wherein fluid is further distributed to a second subset of the plurality of outlets (104c-d) via a second set of inlet openings within the cavity when the operational parameter is below the first threshold value, and wherein the first subset of the plurality of outlets (104a-b) are arranged at different circumferential positions on the rotor to the second subset of the plurality of outlets (104c-d); and the generator further comprising a restrictor configured to provide a constant flow rate of fluid at the rotor inlet, independent of a velocity at which the rotor is rotating, wherein the constant flow rate of fluid received at the rotor inlet is divided between the first subset of the plurality of outlets (104a-b), or the first and second subset of the plurality of outlets (104a-b), such that the velocity at which the fluid is released from the plurality of outlets (104a-d) varies with the operational parameter.