heat flux

Heat flux refers to the rate at which heat energy is transferred through a surface per unit area, usually measured in watts per square meter (W/m²). It indicates how quickly heat is moving through a material or space, whether by conduction, convection, or radiation. For example, a warm cup of coffee radiates heat to your surroundings, and the heat flux describes how much energy moves from the coffee's surface to the air each second, over a specific area. Understanding heat flux helps in designing insulation, managing temperature in systems, and studying how heat moves in natural and engineered environments.