Heat flux or thermal flux is the rate of heat energy transfer through a given surface. The SI derived unit of heat rate is joule per second, or watt. Heat flux is the heat rate per unit area. In SI units, heat flux is measured in . Heat rate is a scalar quantity, while heat flux is a vectorial quantity. To define the heat flux at a certain point in space, one takes the limiting case where the size of the surface becomes infinitesimally small.
Heat flux is often denoted, the subscript q specifying heat rate, as opposed to mass or momentum rate. Fourier's law is an important application of these concepts.
Read more about Heat Flux: Measuring Heat Flux, Relevance To Science and Engineering
Famous quotes containing the words heat and/or flux:
“... often in the heat of noonday, leaning on a hoe, looking across valleys at the mountains, so blue, so close, my only conscious thought was, “How can I ever get away from here? How can I get to where they have books, where I can be educated?” I worked hard, always waiting for something to happen to change things. There came a time when I knew I must make them happen; that no one would do anything about it for me. And I did.”
—Belinda Jelliffe (1892–1979)
“Existence is no more than the precarious attainment of relevance in an intensely mobile flux of past, present, and future.”
—Susan Sontag (b. 1933)