Aerosol-generating system and aerosol-generating article comprising an aerosol-forming substrate

Abstract

An aerosol-generating system is provided, including an aerosol-generating article and an aerosol-generating device, the article having an upstream end and a downstream end, and defines a longitudinal direction and includes an upstream segment and a downstream segment, the upstream segment includes an aerosol-forming substrate having a substrate outer surface with a substrate outer diameter, the downstream segment having a downstream segment outer diameter greater than the substrate outer diameter, the device including a device cavity inner surface having a device cavity inner diameter, the device cavity being configured to receive at least the aerosol-forming substrate, the device further including at least one heating element, and when the aerosol-forming substrate is received in the device cavity, an airflow passage is defined between the substrate outer surface and the device cavity inner surface.

1 .- 14 . (canceled) 
     
     
         15 . An aerosol-generating system, comprising:
 an aerosol-generating article having an upstream end and a downstream end, the aerosol-generating article defining a longitudinal direction between the upstream end and the downstream end, the aerosol-generating article comprising:
 an upstream segment disposed at the upstream end of the aerosol-generating article, the upstream segment comprising an aerosol-forming substrate, the aerosol-forming substrate comprising a substrate outer surface having a substrate outer diameter, and 
 a downstream segment disposed at the downstream end of the aerosol-generating article, the downstream segment having a downstream segment outer diameter, the downstream segment outer diameter being greater than the substrate outer diameter; and 
   an aerosol-generating device comprising:
 a device cavity comprising a device cavity inner surface having a device cavity inner diameter, the device cavity being configured to receive at least the aerosol-forming substrate of the aerosol-generating article, and 
 at least one heating element configured to heat the aerosol-forming substrate when the aerosol-forming substrate is received in the device cavity, 
   wherein, when the aerosol-forming substrate of the aerosol-generating article is received in the device cavity, an airflow passage is defined between the substrate outer surface and the device cavity inner surface, the airflow passage extending in the longitudinal direction along a length of the aerosol-forming substrate.   
     
     
         16 . The aerosol-generating system of  claim 15 , wherein the aerosol-forming substrate further comprises a substrate inner surface having a substrate inner diameter, the substrate inner surface delimiting an inner cavity extending in the longitudinal direction within the aerosol-forming substrate. 
     
     
         17 . The aerosol-generating system of  claim 16 , wherein the substrate inner diameter is between about 60% and about 90% of the substrate outer diameter. 
     
     
         18 . The aerosol-generating system of  claim 16 , wherein a layer of thermally conductive material is disposed on the substrate inner surface. 
     
     
         19 . The aerosol-generating system of  claim 15 , wherein the upstream segment and the downstream segment are arranged in coaxial alignment with a longitudinal axis of the aerosol-generating article. 
     
     
         20 . The aerosol-generating system of  claim 15 , wherein the downstream segment comprises a filter. 
     
     
         21 . The aerosol-generating system of  claim 20 , wherein the downstream segment further comprises at least one of a cooling element and a spacing element disposed between the aerosol-forming substrate and the filter. 
     
     
         22 . The aerosol-generating system of  claim 15 , wherein the substrate outer diameter is between about 50% and about 98% of the downstream segment outer diameter. 
     
     
         23 . The aerosol-generating system of  claim 15 , wherein the substrate outer surface has a transverse cross-section with a circular shape or an oval shape. 
     
     
         24 . The aerosol-generating system of  claim 15 , wherein the aerosol-forming substrate further comprises tobacco cast leaf. 
     
     
         25 . The aerosol-generating system of  claim 15 , wherein the aerosol-forming substrate has a substantially homogenous composition in the longitudinal direction. 
     
     
         26 . The aerosol-generating system of  claim 15 , wherein the aerosol-forming substrate further comprises a first aerosol-forming substrate segment extending in the longitudinal direction, and a second aerosol-forming substrate segment adjacent the first aerosol-forming substrate segment in the longitudinal direction. 
     
     
         27 . The aerosol-generating system of  claim 15 ,
 wherein the device cavity defines the longitudinal direction between an upstream end of the device cavity and a downstream end of the device cavity, and   wherein the at least one heating element comprises a first heating element and a second heating element spaced from each other in the longitudinal direction of the device cavity.   
     
     
         28 . The aerosol-generating system of  claim 15 , wherein the downstream segment outer diameter of the aerosol-generating article is substantially the same as or greater than the device cavity inner diameter.