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∂x∂​(k∂x∂T​)+∂y∂​(k∂y∂T​)+∂z∂​(k∂z∂T​)+q˙​=rhocp​∂t∂T​ a) Equation 2.19 is the general form of the three-dimensional heat diffusion equation. State what do each of the four terms on the left and the single term on the right side represent? b) What would be the form of the equation if there was no heat transfer in the x-direction, there was no heat generation and no energy storage in the system

User Techhero
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Final Answer:

a) In the heat diffusion equation (∂x∂​(k∂x∂T​)+∂y∂​(k∂y∂T​)+∂z∂​(k∂z∂T​)+q˙​=rhocp​∂t∂T​), the terms on the left side represent the rates of temperature change in the x, y, and z directions due to thermal conduction, energy generation or absorption within the system, and the rate of change of temperature with respect to time.

b) If no heat transfer occurred in the x-direction, there was no heat generation, and no energy storage in the system, the equation would simplify to ∂y∂​(k∂y∂T​)+∂z∂​(k∂z∂T​)=rhocp​∂t∂T​.

Step-by-step explanation:

The given heat diffusion equation, ∂x∂​(k∂x∂T​)+∂y∂​(k∂y∂T​)+∂z∂​(k∂z∂T​)+q˙​=rhocp​∂t∂T​, involves terms representing different aspects of heat transfer and energy within a system. The terms ∂x∂, ∂y∂, and ∂z∂ denote the rates of temperature change in the x, y, and z directions, respectively, arising from thermal conduction. The term q˙​ signifies the rate of energy generation or absorption within the system, while rhocp​∂t∂T​ represents the rate of change of temperature with respect to time, considering the system's thermal inertia and energy storage capacity.

In a scenario where no heat transfer occurs in the x-direction, and there is no heat generation or energy storage, simplification of the equation occurs. Removing the term related to heat transfer in the x-direction (∂x∂​(k∂x∂T​)) and the term q˙​ for heat generation results in the equation ∂y∂​(k∂y∂T​)+∂z∂​(k∂z∂T​)=rhocp​∂t∂T​. This simplified form solely accounts for the y and z direction thermal conductivities influencing the temperature change over time, disregarding any x-directional heat transfer or internal heat generation/storage factors. Such simplifications aid in targeted analyses of heat conduction within specific dimensions of a system, facilitating a more focused understanding of temperature distribution and changes.

User Jberryman
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