This episode covers radial diffusion in spherical solids under unsteady states. First, we define a new variable for rearranging the PDE and then discuss the diffusion of various cases based on the PDE.
This episode covers three-dimensional diffusion in a cylindrical solid under an unsteady state. Unlike previous episodes, we discuss how to calculate the concentration when the boundary conditions vary not with time but with radius, azimuth, or height.
This episode covers two-dimensional diffusion in cylindrical solids under unsteady states. First, we describe diffusion in the radial and azimuthal directions when the boundary condition is 0. Then, we discuss various diffusion scenarios when the solids diffuse radially and longitudinally.
In this episode, we describe the diffusion of a cylindrical solid in an unsteady state. First, we explain the Bessel equation to find the solution for Fick’s 2nd law in cylindrical coordinates. Then, we discuss how to calculate the concentration for various diffusion scenarios when the cylindrical solid diffuses only in the radial direction.
In this episode, we describe the diffusion of plate solids within a finite range. How would we calculate the concentration If the diffusion occurs in an unsteady state? To describe this, first, we find a solution for a PDE under specific conditions. Then, we utilize the solution to examine diffusion scenarios for various cases.
In this episode, we discuss about diffusion in a plate solid under unsteady-state conditions. We will utilize Fick’s 2nd Law, a partial differential equation. First, we analyze diffusion in a plate solid with a finite thickness within an infinite medium. And we describe diffusion in a thin film within a semi-infinite medium.
In this episode, we describe diffusion depending on the shape of solids in a steady state. Specifically, we cover the plate, cylindrical, and spherical cases. For each case, we derive the equation from Fick’s 2nd law and explain how to calculate diffusion.
The substance moves from one point to another due to various reasons such as pressure, temperature, and concentration gradients. In this episode, we will briefly discuss diffusion, which is the movement due to concentration gradients. We will introduce Fick’s 1st law, which is a law related to diffusion. Then, based on this law, we will derive Fick’s 2nd law, which describes the diffusion when the concentration changes over time.