Cartridge for an aerosol-generating system

1. A cartridge for an aerosol-generating system, comprising:

a storage portion longitudinally delimited solely by the peripheral walls of a generally circular cylindrical housing configured to hold an aerosol-forming substrate, the housing having an opening provided at a longitudinal open end of the housing; and

a heater assembly comprising at least one heater element fixed to the housing and extending across the opening of the housing,

wherein the at least one heater element defines a plurality of apertures configured to allow fluid to pass through the at least one heater element,

wherein apertures of the plurality of apertures have different sizes, and

wherein the at least one heater element comprises an array of electrically conductive filaments extending along a length of the at least one heater element, the plurality of apertures being defined by interstices between electrically conductive filaments in the array.

2. The cartridge according to claim 1 , wherein a size of the apertures in a first region of the opening is larger than a size of the apertures in a second region of the opening.

3. The cartridge according to claim 1 , wherein aperture size increases towards a center portion of the opening.

4. The cartridge according to claim 1 , wherein the at least one heater element further comprises a plurality of transverse filaments extending transversely to the array of electrically conductive filaments, wherein adjacent filaments in the array of electrically conductive filaments are connected, and wherein the plurality of apertures is defined by the interstices between the electrically conductive filaments in the array and by interstices between transverse filaments in the plurality of transverse filaments.

5. The cartridge according to claim 4 , wherein the interstices between the transverse filaments in the plurality of transverse filaments varies across a length or a width, or a length and a width, of the at least heater element such that the plurality of apertures have different lengths.

6. The cartridge according to claim 4 , wherein at least some transverse filaments of the plurality of transverse filaments extend across only part of a width of the at least one heater element and are staggered along a length of the at least one heater element.

7. The cartridge according to claim 1 , wherein the heater assembly is substantially flat.

8. A cartridge for an aerosol-generating system, comprising:

a storage portion longitudinally delimited solely by the peripheral walls of a generally circular cylindrical housing configured to hold an aerosol-forming substrate, the housing having an opening provided at a longitudinal open end of the housing; and

a heater assembly comprising at least one heater element fixed to the housing and extending across the opening of the housing,

wherein the at least one heater element of the heater assembly comprises an array of electrically conductive filaments extending along a length of the at least one heater element, and a plurality of transverse filaments extending transversely to the array of electrically conductive filaments, and adjacent filaments in the array of electrically conductive filaments are connected,

wherein interstices between electrically conductive filaments in the array of electrically conductive filaments and interstices between the transverse filaments in the plurality of transverse filaments define a plurality of apertures configured to allow fluid to pass through the at least one heater element, and

wherein at least some transverse filaments of the plurality of transverse filaments extend across only part of a width of the at least one heater element and are staggered along a length of the at least one heater element.

9. The cartridge according to claim 8 , wherein the transverse filaments of the plurality of transverse filaments are electrically conductive.

10. The cartridge according to claim 8 , wherein the heater assembly is substantially flat.

11. An aerosol-generating system, comprising:

an aerosol-generating device including a power supply; and

a cartridge removably coupled to the aerosol-generating device, the cartridge comprising:

a storage portion longitudinally delimited solely by the peripheral walls of a generally circular cylindrical housing configured to hold an aerosol-forming substrate, the housing having an opening provided at a longitudinal open end of the housing; and

a heater assembly comprising at least one heater element fixed to the housing and extending across the opening of the housing,

wherein the at least one heater element defines a plurality of apertures configured to allow fluid to pass through the at least one heater element,

wherein apertures of the plurality of apertures have different sizes,

wherein the power supply is configured to supply power to the heater assembly, and

wherein the at least one heater element comprises an array of electrically conductive filaments extending along a length of the at least one heater element, the plurality of apertures being defined by interstices between electrically conductive filaments in the array.

12. The aerosol-generating, system according to claim 11 , wherein the aerosol-generating system is an electrically operated smoking system.

13. A method of manufacturing a cartridge for an aerosol-generating system, the method comprising:

providing a storage portion longitudinally delimited solely by the peripheral walls of a generally circular cylindrical housing having an opening provided at a longitudinal open end of the housing;

filling the storage portion with an aerosol-forming substrate; and

providing a heater assembly comprising at least one heater element extending across the opening of the housing,

wherein the at least one heater element of the heater assembly has a plurality of apertures configured to allow fluid to pass through the at least one heater element,

wherein apertures of the plurality of apertures have different sizes, and

wherein the at least one heater element comprises an array of electrically conductive filaments extending along a length of the at least one heater element, the plurality of apertures being defined by interstices between electrically conductive filaments in the array.

14. A method of manufacturing a cartridge for an aerosol-generating system, the method comprising:

providing a storage portion longitudinally delimited solely by the peripheral walls of a generally circular cylindrical housing having an opening provided at a longitudinal open end of the housing;

filling the storage portion with an aerosol-forming substrate; and

providing a heater assembly comprising at least one heater element extending across the opening of the housing,

wherein the at least one heater element of the heater assembly comprises an array of electrically conductive filaments extending along a length of the at least one heater element, and a plurality of electrically conductive transverse filaments extending transversely to the array of electrically conductive filaments, and adjacent filaments in the array of electrically conductive filaments are connected,

wherein interstices between electrically conductive filaments in the array of electrically conductive filaments and interstices between electrically conductive transverse filaments in the plurality of electrically conductive transverse filaments define a plurality of apertures configured to allow fluid to pass through the at least one heater element, and

wherein at least some electrically conductive transverse filaments of the plurality of electrically conductive transverse filaments extend across only part of a width of the at least one heater element and are staggered along a length of the at least one heater element.

15. The method according to claim 13 , wherein the at least one heater element is formed by etching.

16. The method according to claim 14 , wherein the at least one heater element is formed by etching.