Consider the plane wall of Figure 3.1, separating hot and cold fluids at temperatures
The temperature distribution within the wall and heat flux.
Answer to Problem 3.1P
The expression of temperature distribution is
Explanation of Solution
Given:
The temperature of hot fluid is
The temperature of cold fluid is
Formula Used:
The expression of one dimensional heat equation is given by,
The expression of convection heat rate is given by,
Calculation:
Assume steady state, constant material properties with no heat generation.
The heat equation is calculated as,
Integrate the above equation once.
Integrate above equation again.
Apply boundary condition at
At
At
The surface temperature at
The surface temperature at
Solve all the equation to find unknown.
The temperature distribution is calculated as,
The heat flux is calculated as,
Conclusion:
Therefore, the expression of temperature distribution is
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Chapter 3 Solutions
Fundamentals of Heat and Mass Transfer
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