Thermal boundary layer is a region wherea)Inertia terms are of the sam...
Thermal boundary layer is a region wherea)Inertia terms are of the sam...
Thermal boundary layer is a region where convection terms are of the same order of magnitude as dissipation terms.
The thermal boundary layer is a region that forms near a solid surface when there is a flow of fluid over the surface. In this region, the fluid flow and heat transfer are significantly influenced by the presence of the solid surface. The thermal boundary layer is characterized by a gradual transition from the temperature at the solid surface to the temperature of the bulk fluid.
Convection and Dissipation Terms
- Convection: Convection is the transfer of heat between a solid surface and a moving fluid. It occurs due to the bulk motion of the fluid and is characterized by the convective heat transfer coefficient.
- Dissipation: Dissipation refers to the conversion of mechanical energy into thermal energy within a fluid. It occurs due to the viscous effects within the fluid and is characterized by the dissipation rate.
Order of Magnitude
- The order of magnitude refers to the scale or relative size of different quantities or terms. When two terms are of the same order of magnitude, it means that they are comparable in size and have a similar impact on the overall system.
Explanation of the Correct Answer (Option B)
- In the given options, the correct answer is option B, which states that in the thermal boundary layer, convection terms are of the same order of magnitude as dissipation terms.
- This means that the convective heat transfer and the dissipation rate are comparable in size within the thermal boundary layer.
- The convection terms account for the heat transfer between the solid surface and the fluid, while the dissipation terms account for the conversion of mechanical energy into thermal energy within the fluid.
- In the thermal boundary layer, the fluid motion and heat transfer are strongly influenced by the presence of the solid surface, leading to a comparable magnitude of convection and dissipation terms.
- This indicates that both convective heat transfer and dissipation play a significant role in determining the overall heat transfer characteristics within the thermal boundary layer.
- Therefore, the correct answer is option B, convection terms are of the same order of magnitude as dissipation terms, in the thermal boundary layer.
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