US 12,065,250 B2
Recirculation ground maintenance mode
Brian R. Shea, Windsor, CT (US); Peter Zywiak, Avon, CT (US); and Luke Martin, Rockton, IL (US)
Assigned to HAMILTON SUNDSTRAND CORPORATION, Charlotte, NC (US)
Filed by Hamilton Sundstrand Corporation, Charlotte, NC (US)
Filed on Dec. 9, 2020, as Appl. No. 17/116,224.
Prior Publication US 2022/0177141 A1, Jun. 9, 2022
Int. Cl. B64D 13/06 (2006.01); B64D 13/02 (2006.01); B64D 13/08 (2006.01); B64D 41/00 (2006.01)
CPC B64D 13/06 (2013.01) [B64D 13/02 (2013.01); B64D 13/08 (2013.01); B64D 41/00 (2013.01); B64D 2013/0611 (2013.01); B64D 2013/0618 (2013.01); B64D 2013/0688 (2013.01)] 6 Claims
OG exemplary drawing
 
1. An aircraft air conditioning system comprising:
a lower cooling zone including a lower recirculation heat exchanger, the lower recirculation heat exchanger configured to receive cabin air from a cabin and to convert the cabin air into lower cooled recirculated cabin air;
a lower recirculation fan is configured to deliver a first portion of the cabin air to the lower recirculation heat exchanger in response to receiving the power from the power system, and wherein the lower recirculation heat exchanger is configured to convert the first portion of the cabin air into the lower cooled recirculated cabin air;
an upper cooling zone including an upper recirculation heat exchanger, the upper recirculation heat exchanger configured to receive the cabin air from the cabin and to convert the cabin air into upper cooled recirculated cabin air;
an upper recirculation fan configured to deliver a second portion of the cabin air to the upper recirculation heat exchanger in response to receiving the power from the power system, and convert the second portion of the cabin air into the upper cooled recirculated cabin air;
a manifold configured to output cooled cabin supply air that is delivered to the cabin;
a supplemental cooling system (SCS) configured to recirculate a heat transfer fluid to and from one or both of the lower recirculation heat exchanger and the upper recirculation heat exchanger;
a pressurization air cycle kit (PACK) in signal communication with the power system to selectively receive the power, the PACK configured to condition fresh air to generated conditioned fresh air and output the conditioned fresh air to the manifold in response to receiving the power; and
a power system configured to selectively deliver power to the lower cooling zone, the lower recirculation fan, the upper cooling zone, and the upper recirculation fan;
a controller in signal communication with the power system, the controller configured to determine a target temperature of the cabin and invokes a recirculation ground maintenance mode that commands the power system to deliver power to one or both of the lower cooling zone and the upper cooling zone so that a temperature of the cabin reaches the target temperature,
wherein in response to invoking only the lower upper cooling zone during the recirculation ground maintenance mode, the controller commands the power system to deliver power to the lower recirculation fan while commanding the power system to disconnect from power to the upper recirculation fan, and the SCS recirculates the heat transfer fluid to and from the lower recirculation heat exchanger,
wherein in response to invoking only the upper cooling zone during the recirculation ground maintenance mode, the controller commands the power system to deliver power to the upper recirculation fan while commanding the power system to disconnect from power to the lower recirculation fan, and the SCS recirculates the heat transfer fluid to and from the upper recirculation heat exchanger;
wherein in response to invoking a combination of the lower and upper cooling zones during the recirculation ground maintenance mode, the controller disconnects power to the ECS while connecting the power supply to the lower and upper recirculation fans and the SCS recirculates the heat transfer fluid to and from both the lower recirculation heat exchanger and the upper recirculation heat exchanger such that lower cooled recirculated cabin air is delivered to the manifold which outputs the mixed cooled cabin supply air to the cabin, and the upper cooled recirculated cabin air bypasses the manifold such that the upper cooled recirculated cabin air avoids mixing with the lower cooled recirculated cabin air provided by the lower cooling zone and is delivered directly to the cabin.