Air-conditioning system with icing protection for an aircraft

1. An aircraft air-conditioning system ( 1 ) for an aircraft containing a plurality of zones ( 2 , 4 ), comprising

a cold air source,

a first line ( 6 ) for feeding cold, non-recirculated air at an actual temperature T 1 act. , wherein the first line ( 6 ) is fed from the cold air source and the first line ( 6 ), downstream and/or upstream of a branching point ( 10 ) at which air is tapped off for a plurality of zones ( 2 , 4 ), feeds cold air at least to one further region that is provided for passengers and/or freight,

a second line ( 14 ) which branches off a portion of the air from the first line ( 6 ) at the branching point ( 10 ) and feeds this air to the plurality of zones ( 2 , 4 ) of the aircraft, wherein warm air is fed into the second line ( 14 ) through a first trim valve ( 12 ) so that the air in the second line ( 14 ) is heated to the actual temperature T 2 act higher than about 0° C., and

a first zone feed line ( 24 ) feeding the air downstream of the first trim valve ( 12 ) to a first zone ( 2 ),

wherein in the first zone feed line ( 24 ) a second trim valve ( 26 ) is arranged, through which warm air is fed into the first zone feed line ( 24 ) so that the air in the first zone feed line ( 24 ) is heated to the actual temperature Tzf 1 act. ,

characterised in that the first line ( 6 ) feeds air to a mixing chamber, to which is also fed recirculated air.

2. The aircraft air-conditioning system ( 1 ) according to claim 1 , characterised in that the cold air source is an air-conditioning PACK.

3. The aircraft air-conditioning system ( 1 ) according to claim 1 ,

characterised in that the temperature of the air in the first line ( 6 ) is between about −10° C. and about 0° C.

4. The aircraft air-conditioning system ( 1 ) according to claim 1 ,

characterised in that a second zone feed line ( 18 ) feeds air downstream of the first trim valve ( 12 ) to a second zone ( 4 ).

5. The aircraft air-conditioning system ( 1 ) according to claim 1 ,

characterised in that a heating device ( 20 ) is arranged in the second zone feed line ( 18 ), which heats up the air in the second zone feed line ( 18 ) to the actual temperature Tzf 2 act. .

6. The aircraft air-conditioning system ( 1 ) according to claim 4 ,

characterised in that the second zone ( 4 ) requires a smaller amount of warm air than the first zone ( 2 ).

7. The aircraft air-conditioning system ( 1 ) according to claim 1 ,

characterised in that the aircraft air-conditioning system ( 1 ) furthermore includes a temperature sensor ( 16 ), which senses the actual temperature T 2 act. of the air in the second line ( 14 ) downstream of the first trim valve ( 12 ), and includes a regulating device which is adapted to control the first trim valve ( 12 ) and the second trim valve ( 26 ).

8. The aircraft air-conditioning system ( 1 ) according to claim 7 ,

characterised in that the regulating device controls the first trim valve ( 12 ) in such a way that the actual temperature T 2 act. of the air in the second line ( 14 ) corresponds approximately to the set temperature Tzf 2 set of the air in the second zone feed line ( 18 ).

9. The aircraft air-conditioning system ( 1 ) according to claim 7 ,

characterised in that the aircraft air-conditioning system ( 1 ) furthermore includes a first zone feed line temperature sensor ( 28 ), which senses the actual temperature Tzf 1 act. of the air in the first zone feed line ( 24 ) downstream of the trim valve ( 26 ), and includes a second zone feed line temperature sensor ( 22 ), which senses the actual temperature Tzf 2 act. of the air in the second zone feed line ( 18 ) downstream of the heating device ( 20 ).

10. The aircraft air-conditioning system ( 1 ) according to claim 7 ,

characterised in that if the set temperature Tzf 1 set of the air in the first zone feed line ( 24 ) is higher than the set temperature Tzf 2 set of the air in the second zone feed line ( 18 ), then the regulating device controls the first trim valve ( 12 ) in such a way that the actual temperature T 2 act. of the air in the second line ( 14 ) corresponds approximately to the set temperature Tzf 2 set of the air in the second zone feed line ( 18 ).

11. The aircraft air-conditioning system ( 1 ) according to claim 7 ,

characterised in that if the set temperature Tzf 1 set of the air in the first zone feed line ( 24 ) is lower than the set temperature Tzf 2 set of the air in the second zone feed line ( 18 ), then the regulating device controls the first trim valve ( 12 ) in such a way that the actual temperature T 2 act. of the air in the second line ( 14 ) corresponds approximately to the set temperature Tzf 1 set of the air in the first zone feed line ( 24 ).

12. The aircraft air-conditioning system ( 1 ) according to claim 7 ,

characterised in that if the set temperature Tzf 1 set of the air in the first zone feed line ( 24 ) is higher than the set temperature Tzf 2 set of the air in the second zone feed line ( 18 ), then the regulating device controls the first trim valve ( 12 ) in such a way that the actual temperature T 2 act. of the air in the second line ( 14 ) is increased, and controls the heating device ( 20 ) in such a way that the heating device ( 20 ) heats the air in the second zone feed line ( 18 ) to the set temperature Tzf 2 set .

13. The aircraft air-conditioning system ( 1 ) according to claim 7 ,

characterised in that if the set temperature Tzf 1 set of the air in the first zone feed line ( 24 ) is lower than the set temperature Tzf 2 set of the air in the second zone feed line ( 18 ), then the regulating device controls the first trim valve ( 12 ) in such a way that the actual temperature T 2 act. of the air in the second line ( 14 ) is increased, and controls the second trim valve ( 26 ) in such a way that the air in the first zone feed line ( 24 ) is heated to the set temperature Tzf 1 set .

14. The aircraft air-conditioning system ( 1 ) according to claim 7 ,

characterised in that the aircraft air-conditioning system ( 1 ) includes a first zone temperature sensor ( 32 ), which senses the actual temperature Tz 1 act. of the air in the first zone ( 2 ), wherein the regulating device determines the set temperature Tzf 1 set of the air in the first feed line ( 24 ) from the actual temperature Tz 1 act. and from the set temperature Tz 1 set of the air in the first zone ( 2 ).

15. The aircraft air-conditioning system ( 1 ) according to claim 7 ,

characterised in that the aircraft air-conditioning system ( 1 ) includes a second zone temperature sensor ( 30 ), which senses the actual temperature Tz 2 act. of the air in the second zone ( 4 ), wherein the regulating device determines the set temperature Tzf 2 set of the air in the second feed line ( 18 ) from the actual temperature Tz 2 act. and from the set temperature Tz 2 set of the air in the second zone ( 4 ).

16. A method for the air conditioning of a plurality of zones ( 2 , 4 ) in an aircraft, comprising the following steps:

providing an aircraft air conditioning system according to claim 1 ;

feeding non-recirculated cold air at an actual temperature T 1 act. in a first line ( 6 );

branching off part of the cold air into a second line ( 14 ) at a branching point ( 10 );

passing the cold air in the first line ( 6 ) to further zones, which are located downstream and/or upstream of the branching point ( 10 );

feeding warm air via a first trim valve ( 12 ) to the second line ( 14 ), so that the air in the second line ( 14 ) is heated to an actual temperature T 2 act. that is higher than 0° C.;

passing a part of the air in the second line ( 14 ) through a first zone feed line ( 24 ) into a first zone ( 2 ); and

feeding warm air through a second trim valve ( 26 ) into the first zone feed line ( 24 ), so that the air in the first zone feed line ( 24 ) is heated to the actual temperature Tzf 1 act. ,

characterised by supplying air by the first line to a mixing chamber, to which is also fed recirculated air.

17. The method according to claim 16 , characterised by the following steps:

leading part of the air in the second line ( 14 ) through a second zone feed line ( 18 ) into a second zone ( 4 ); and

heating the air in the second zone feed line ( 18 ) to the actual temperature Tzf 2 act. with a heating device ( 20 ).

18. The aircraft air-conditioning system ( 1 ) according to claim 2 ,

characterised in that a second zone feed line ( 18 ) feeds air downstream of the first trim valve ( 12 ) to a second zone ( 4 ).

19. The aircraft air-conditioning system ( 1 ) according to claim 2 ,

characterised in that a heating device ( 20 ) is arranged in the second zone feed line ( 18 ), which heats up the air in the second zone feed line ( 18 ) to the actual temperature Tzf 2 act. .

20. The aircraft air-conditioning system ( 1 ) according to claim 2 ,

characterised in that the aircraft air-conditioning system ( 1 ) furthermore includes a temperature sensor ( 16 ), which senses the actual temperature T 2 act. of the air in the second line ( 14 ) downstream of the first trim valve ( 12 ), and includes a regulating device which is adapted to control the first trim valve ( 12 ) and the second trim valve ( 26 ).