13 Contributions. Literature is a beautiful and complex artistic expression. In ancient times, people would use symbols and pictures to portray a moment in time. Writing, however, gave us a wayâ¦ to convey not only documented history, but the feelings that went along with those moments.
Heat flux and radiative flux are specific cases of energy flux that involve the rate of transfer of heat and radiation (photons) respectively. Energy flux is a function of time as well as area, and has units of J/m 2 /s or W/m 2. It is sometimes also referred to as flux density. In more technical terms, flux density is defined as the energy travelling over an area perpendicular to the flow of energy divided by time and by area. Four types of energy fluxes for ideal (flat and smooth) surfaces have been identified so far.
The flux is proportional to the average velocity and thus inversely proportional to the square root of the molecular mass, just as in gas diffusion. This is Grahamâs law of effusion. A process similar to effusion occurs when gases dissolved in liquids diffuse across membranes.