US 12,168,522 B2
Auxiliary power unit system of an aircraft
Miguel Ángel Soto Carril, Getafe (ES)
Assigned to Airbus Operations S.L.U., Getafe (ES)
Filed by Airbus Operations S.L.U., Getafe (ES)
Filed on May 3, 2023, as Appl. No. 18/311,331.
Claims priority of application No. 22382511.8 (EP), filed on May 27, 2022.
Prior Publication US 2023/0382553 A1, Nov. 30, 2023
Int. Cl. B64D 41/00 (2006.01); F03D 9/25 (2016.01); F03D 80/60 (2016.01)
CPC B64D 41/00 (2013.01) [F03D 9/25 (2016.05); F03D 80/60 (2016.05); B64D 2041/002 (2013.01); F05B 2220/10 (2013.01); F05B 2220/31 (2013.01); F05B 2220/50 (2013.01); F05B 2220/706 (2013.01); F05B 2260/20 (2013.01)] 15 Claims
OG exemplary drawing
 
1. An auxiliary power unit system of an aircraft comprising:
an auxiliary power unit (APU),
a cooling unit for the APU comprising at least one heat exchanger,
an air inlet in fluid communication with at least one of the APU or with the cooling unit,
an air inlet door unit located at the air inlet to allow an air flow from outside the aircraft to enter the air inlet,
a first duct configured to draw air into the APU and having an entrance in fluid communication with the air inlet,
a second duct having an entrance in fluid communication with the air inlet,
the heat exchanger being at least partially located within the second duct,
an air turbine located within the second duct downstream the heat exchanger, and
an electrical generator coupled to the air turbine so that the air turbine and the electrical generator are configured to convert energy of an air flow in the second duct into electrical energy.