Definition - What does Diffusion Coefficient mean?
The diffusion coefficient is the proportion of the constant in between molar flux brought about by molecular diffusion and the driving force or gradient for diffusion. It is commonly encountered in physical chemistry equations, such as Fick's law as well as others.
The rule is, the higher the levels of diffusivity of a certain substance to another, the faster the diffusion rate by both of the substances. It is given the SI unit of length2/time or m2/s.
The diffusion coefficient is also known as diffusivity.
Corrosionpedia explains Diffusion Coefficient
Diffusion coefficients are among the variables that induce corrosion. With this, accurate computation of diffusivity must be performed to prevent corrosion.
Measuring the diffusion coefficient is vital in predicting corrosion in concrete substances. This is used in industries such as maritime, and in structures such as highways, bridge decks and other concrete.
The diffusion coefficient is the physical constant that depends on properties like the size of molecules of the substance undergoing diffusion. Apart from molecular size, other factors that affect diffusivity are pressure and temperature. The diffusivity of one particular substance to another is typically identified through experimenting.
Diffusion coefficients can be computed in liquids, gases and multiple media that usually involve factors such as changes in temperature and pressure. Close monitoring is important since diffusivity in liquid and gaseous phases can vary, which means that diffusion involves molecular movement through molecule layers of similar or different substances.
This only implies that the diffusion coefficient of various substances differs depending on the phases and factors involved. Proper levels should be maintained all the time in order to mitigate or prevent the damaging effects of corrosion.