Transient Heat Diffusion: Lumped Capacitance Model

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Description

This lecture covers the transient heat diffusion phenomenon, introducing the lumped capacitance model and its application in solving transient heat conduction under convective cooling. The instructor explains the Biot number, spatial effects, and provides a generalized solution for planar, radial, and spherical geometries. The lecture also discusses the assumptions behind the model, such as high thermal conductivity ensuring uniform temperature in the solid and the impact of liquid volume on temperature stability. An electrical analogy is presented to aid in understanding the cooling process, emphasizing the importance of the Biot number in determining heat transfer characteristics. Practical examples, like using a thermocouple for temperature measurement in a gas stream, are used to illustrate the concepts.

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https://mediaspace.epfl.ch/media/0_4r07ch2g

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