An aerosol-generating article is provided for producing an inhalable aerosol when heated, the aerosol-generating article including: a hollow cylindrical rod of aerosol-generating substrate; a wrapper circumscribing the hollow cylindrical rod; and a hollow tube extending along a longitudinal axis of the hollow cylindrical rod and defining a central airflow channel of the aerosol-generating article, the hollow tube including a plurality of openings extending through a wall of the hollow tube, such that the aerosol-generating substrate in the hollow cylindrical rod is in fluid communication with the central airflow channel through the plurality of openings, and such that a ratio between a cumulative cross-sectional area of the plurality of openings and a cross-sectional area of the central airflow channel is from about 0.042 to about 0.672.