Aerosol generating system and cartridge with leakage protection

An aerosol-generating system, comprising:

• a reservoir holding an aerosol-generating substrate in condensed form;
• a housing comprising an air inlet, an air outlet, an airflow passage extending therebetween, and a chamber;
• a liquid-permeable heating element extending generally parallel to the airflow passage, one side of the liquid-permeable heating element being in fluidic communication with the reservoir and an opposite side of the liquid-permeable heating element being in fluidic communication with the chamber, the liquid-permeable heating element configured to heat the aerosol-generating substrate in condensed form to generate a vapour within the chamber;
• and
• a gas-permeable element extending generally parallel to the airflow passage, one side of the gas-permeable element being in fluidic communication with the chamber and an opposite side of the gas-permeable element being in fluidic communication with the airflow passage,
• wherein the gas-permeable element is configured to allow transport of the vapour into the airflow passage and to inhibit transport of the condensed form of the aerosol-generating substrate into the airflow passage, and
• wherein the vapour at least partially condenses into an aerosol within the airflow passage.

A method for generating an aerosol, the method comprising:

• holding, by a reservoir, an aerosol-generating substrate in condensed form;
• heating, by a liquid-permeable heating element, the aerosol-generating substrate to generate a vapour within a chamber;
• allowing transport, by a gas-permeable element, of the vapour into an airflow passage;
• inhibiting transport, by the gas-permeable element, of the condensed form of the aerosol-generating substrate into the airflow passage;
• and
• at least partially condensing the vapour into an aerosol within the airflow passage.