Diffusion Equations and Fick's Laws
Bahman Zohuri, Seyed Kamal Mousavi Balgehshiri, Guglielmo Lomonaco · 2025
Adolf Fick developed the rules of diffusion in 1855, and they offer a basic foundation for comprehending the movement of particles from high-concentration regions to low-concentration regions. In disciplines including physics, chemistry, biology, and materials science, these principles are crucial for simulating the movement of gases, liquids, and solutes through various media. According to Fick&s;s First Law, the flux of particles is proportional to the concentration gradient, which means that the diffusion coefficient D determines how quickly particles will migrate from regions of higher to lower concentration. Fick&s;s Second Law, a time-dependent equation that explains how particle concentration varies over time, can be inferred from his First Law. The diffusion equation is mathematically equal to Fick&s;s Second Law. When combined, these principles are essential for figuring out the diffusion coefficient and forecasting how diffusive processes will behave over time.