Viscous Heat Generation — Lesson 2

This lesson covers the concept of viscous heat generation, focusing on the transport phenomena of non-Newtonian fluids. It explains how mechanical energy converts into thermal energy, leading to heat generation known as viscous dissipation. The lesson provides examples of viscous heat generation in motor vehicles and conveyors in chemical industries. It also discusses the impact of high velocity and high apparent viscosity on heat generation. The lesson further delves into the mathematical derivation of temperature distribution in different geometries and the impact of various factors such as velocity, pressure force, and curvature effects on the temperature profile. It concludes with a discussion on the viscous heat generation in slit flow.

Video Highlights

01:08 - Discussion on the concept of viscous dissipation and its role in heat generation.
04:59 - Detailed solution of the problem, including the derivation of the temperature distribution.
43:16 - Explanation of the problem of viscous heat generation in slit flow.
52:14 - Conclusion and references for further reading.

Key Takeaways

• Viscous heat generation occurs when mechanical energy converts into thermal energy, leading to heat generation known as viscous dissipation.
• The temperature profile in a system can be affected by the velocity profile, but not vice versa.
• The velocity profile remains linear regardless of whether the fluid is Newtonian or obeys a power-law fluid behavior.
• The temperature profile for viscous heat generation in a slit flow differs based on the boundary conditions at the moving surface.