What is the term for heat transfer that occurs through direct contact between materials?

The term for heat transfer that occurs through direct contact between materials is conduction. This process involves the transfer of thermal energy from one object to another when they are in physical contact. Molecules in a hotter object, which have higher kinetic energy, collide with the molecules of a cooler object, transferring some of their kinetic energy to the cooler molecules. This continues until thermal equilibrium is reached, meaning both objects reach the same temperature.

Conduction is particularly important in fire investigations as it plays a critical role in how fire spreads through materials that are in contact with one another, such as building components. Understanding conduction is essential for fire investigators to determine the sequence of events during a fire incident.

Radiation, on the other hand, involves the transfer of heat through electromagnetic waves and does not require direct contact. Convection refers to the transfer of heat through fluids (liquids or gases) caused by the motion of the fluid itself. Advection is a specific type of convection that involves the horizontal movement of fluid, typically in the context of air or water currents. These concepts are related to heat transfer but do not involve direct contact like conduction does.