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What does “Frozen-In” Mean?

What does “Frozen-In” Mean?

For highly conductive plasma (conductivity (σ) → ∞), we often say that the plasma is ‘frozen-in’ the magnetic field lines, but what does this mean physically? Let’s begin by examining the mathematical (forgive me) behavior of the flow. From Ohm’s Law and Ampere’s Law1  Solve for E Take the curl of both sides By Faraday’s Law and the vector identify for Recall the Maxwell equation that says that there can be no magnetic monopoles and distribute the negative sign where…

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Prandtl Number

Prandtl Number

The Prandtl Number is an intrinsic property of a fluid that describes which mechanism dominates heat transfer. Specifically, it is the ratio of momentum diffusivity (how quickly energy is dispersed by convection) to thermal diffusivity (how quickly energy is dispersed as heat). In the abstract, the Prandtl Number describes how quickly a “velocity wave” moves relative to the speed of the “thermal wave” in the fluid. Here, Pr is the Prandtl Number, is the specific heat, is the dynamic viscosity,…

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