Numerical estimation for intumescent thermal protection using one-dimensional IHCP

Intumescent coatings are an important group of passive fire protection materials, representing about one third of steel fire protection costs. This insulating system is made of four different chemical compounds that can be classified as: a carbonisation agent, an acid source, a foaming agent and a catalyst. When protecting a steel structure under fire conditions, the intumescent paint is heated, beginning to melt, to bubble and to swell, forming a multi-cellular barrier which decreases the heat transfer from the fire to the substrate. The film behaviour is characterized by an expansion and mass loss, producing a foam char with a geometry that varies from 5 to 200 times its original volume. In order to design this type of protection, the intumescence physical and thermal behaviour must be acknowledged, being the thickness and the effective thermal conductivity the key parameters during this process