Aerosol-generating article having an aerosol-cooling element

A heated aerosol-generating article, comprising:

• a plurality of elements assembled in the form of a rod by means of a paper wrapper, the plurality of elements including an aerosol-forming substrate, an aerosol-cooling element located downstream from the aerosol-forming substrate within the rod, and a mouthpiece filter located downstream from the aerosol-cooling element within the rod, wherein
• a first end of the mouthpiece filter forms a mouth end of the rod and the aerosol-cooling element is disposed adjacent a second end of the mouthpiece filter,
• the rod further comprises a spacer element located between the aerosol-forming substrate and the aerosol-cooling element within the rod, the aerosol-forming substrate being disposed immediately adjacent to the spacer element,
• outer surfaces of each of the aerosol-forming substrate, the spacer element, the aerosol-cooling element, and the mouthpiece filter abut an inner surface of the paper wrapper,
• the aerosol-forming substrate is formed from a homogenised tobacco material having an aerosol former content of between 5% and 30% by weight on a dry weight basis, and in which the aerosol-cooling element is formed from a polymeric sheet that has been crimped such that the polymeric sheet has a plurality of parallel ridges and corrugations that, in the heated aerosol-generating article, extend in a longitudinal direction therein, and gathered such that the aerosol-cooling element comprises a plurality of longitudinally extending channels and has a longitudinal porosity of between 50% and 90% in the longitudinal direction, the longitudinal porosity being derived from a ratio of a cross-sectional area of material forming the aerosol-cooling element and an internal cross-sectional area of the heated aerosol-generating article at a portion containing the aerosol-cooling element,
• the aerosol-cooling element has a total surface area of between 300 mm2 per mm length of the aerosol-cooling element and 1000 mm2 per mm length of the aerosol-cooling element,
• the external diameter of the article is between 5 mm and 12 mm,
• wherein the aerosol-cooling element comprises a polymeric sheet material formed of polylactic acid,
• a temperature of a stream of aerosol drawn through the aerosol-cooling element is lowered by more than 20° C., and
• a water vapor content of an aerosol stream drawn through the aerosol-cooling element is lowered by between about 20% and about 90%.