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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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- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning