4. Two aluminum blocks with different dimensions, but the same mass are shown in the figure. The dimensions of block 1 are 0.25 cm in thickness, 3 cm in width, and 36 cm in length. The dimensions of block 2 are 3 cm for each side of the cube. Aluminum has a density of 2700 kg/m³ and a specific heat capacity of 900 J/kg-°C. The value of the heat transfer coefficient to the surrounding air is 10 W/m²-°C. 0.25 cm 36 cm 3 cm 3 cm Block 1 3 cm Block 2 3 cm Complete the following. (a) Calculate thermal time constant (in min) for both blocks. (b) Each block is heated to an initial temperature 120 °C and then allowed to cool in the surrounding air which is at 20 °C. Write a script file in MATLAB® that plots the temperature as a function of time, T(t), for both blocks on the same graph. Plot the temperature of block 1 using a solid black line and the temperature of block 2 using a dotted black line. Plot for a duration equal to four of the longer time constant between blocks 1 and 2. The time axis should be in units of minutes.

4. Two aluminum blocks with different dimensions, but the same mass are shown in the figure. The dimensions of block 1 are 0.25 cm in thickness, 3 cm in width, and 36 cm in length. The dimensions of block 2 are 3 cm for each side of the cube. Aluminum has a density of 2700 kg/m³ and a specific heat capacity of 900 J/kg-°C. The value of the heat transfer coefficient to the surrounding air is 10 W/m²-°C. 0.25 cm 36 cm 3 cm 3 cm Block 1 3 cm Block 2 3 cm Complete the following. (a) Calculate thermal time constant (in min) for both blocks. (b) Each block is heated to an initial temperature 120 °C and then allowed to cool in the surrounding air which is at 20 °C. Write a script file in MATLAB® that plots the temperature as a function of time, T(t), for both blocks on the same graph. Plot the temperature of block 1 using a solid black line and the temperature of block 2 using a dotted black line. Plot for a duration equal to four of the longer time constant between blocks 1 and 2. The time axis should be in units of minutes.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.10P: 5.10 Experiments have been performed on the temperature distribution in a homogeneous long cylinder...

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