Non-Isothermal Diffusive Mass Transfer and Forced Convective Mass Transfer — Lesson 2

This lesson covers the transport phenomena of Non-Newtonian fluids, focusing on two types of problems: Non-Isothermal Diffusive Mass Transfer and Forced Convective Mass Transfer. It explains the concept of diffusion through a non-isothermal spherical film and how the diffusivity changes with temperature. The lesson also discusses the applications of these phenomena in chemical engineering, such as in the drying of droplets and catalyst surfaces. It further elaborates on how to solve problems related to these phenomena using mathematical equations and boundary conditions. For instance, it explains how to calculate the mass transfer rate in moles per second and how to derive the concentration profile under non-isothermal conditions.

Video Highlights

01:02 - Explanation of the system involving a droplet and a gas film, and the variables involved in the problem.
13:11 -Explanation of how to calculate the rate of mass transfer in terms of moles per time.
28:03 - Explanation of the concept of forced convective mass transfer and how to solve a problem involving it.
40:01 - Discussion on the boundary conditions and how to solve the problem using combined variable approach.
63:27 -Conclusion of the lesson with the final expressions for concentration profile and mass rate.

Key Takeaways

• Non-Newtonian fluids exhibit different transport phenomena, including Non-Isothermal Diffusive Mass Transfer and Forced Convective Mass Transfer.
• The diffusivity of a component in a non-isothermal system changes with temperature, affecting the mass transfer process.
• The penetration depth of a gas into a liquid film during forced convective mass transfer is significantly smaller than the film thickness.
• Mathematical equations and boundary conditions are essential tools for solving problems related to these phenomena.
• The mass transfer rate and concentration profile under non-isothermal conditions can be calculated using specific formulas.