Question 1 (a) Some 500 level students always see heat transfer class as unnecessary and time...

  

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Question 1 (a) Some 500 level students always see heat transfer class as unnecessary and time wasting, their arguments were based on the fact that, they had already taken courses in thermodynamics in their lower levels. Now that you have already taken heat transfer course in this semester, (i) You need to first critically analyze their views by comparing both thermodynamics and heat transfer courses, that is, from your own perspective, and (ii) Convince people what the present life would have been without heat transfer knowledge, especially to mechanical engineers. (b) In Fourier's heat conduction equation, negative sign normally appeared in the front. Explain what the negative sign in front represents? (c) When standing in a cool room that has both carpet and tile flooring with one bare foot on each type of material, the tile will feel colder than the carpet. Explain why. (d) Demonstrate the analogy between thermal resistance and electrical resistance concept in heat conduction. (e) Under the "shape factor" in radiative heat transfer, what does the below equation represent? You should support your explanations with a simple sketch. F11 = F22=F33=0... (f) What is Prandtl number (Pr)? Hence, what is the physical interpretation of figure 1 below? Liquid metals 0.01 0.1 Gases Light organic liquids Liquid water 1.0 Prandtl number, Pr Figure 1 10 100 Oils " (31 Marks) Question 2 (a) Compare and contrast: Heat transfer versus Mass transfer (b) State Fick's law of diffusion and write its equivalent equation form (c) By using the semi empirical equation proposed by Gilliland, calculate the diffusion coefficient for CO₂ in air at atmospheric pressure and 25°C. Question 1 (a) Some 500 level students always see heat transfer class as unnecessary and time wasting, their arguments were based on the fact that, they had already taken courses in thermodynamics in their lower levels. Now that you have already taken heat transfer course in this semester, (i) You need to first critically analyze their views by comparing both thermodynamics and heat transfer courses, that is, from your own perspective, and (ii) Convince people what the present life would have been without heat transfer knowledge, especially to mechanical engineers. (b) In Fourier's heat conduction equation, negative sign normally appeared in the front. Explain what the negative sign in front represents? (c) When standing in a cool room that has both carpet and tile flooring with one bare foot on each type of material, the tile will feel colder than the carpet. Explain why. (d) Demonstrate the analogy between thermal resistance and electrical resistance concept in heat conduction. (e) Under the "shape factor" in radiative heat transfer, what does the below equation represent? You should support your explanations with a simple sketch. F11 = F22=F33=0... (f) What is Prandtl number (Pr)? Hence, what is the physical interpretation of figure 1 below? Liquid metals 0.01 0.1 Gases Light organic liquids Liquid water 1.0 Prandtl number, Pr Figure 1 10 100 Oils " (31 Marks) Question 2 (a) Compare and contrast: Heat transfer versus Mass transfer (b) State Fick's law of diffusion and write its equivalent equation form (c) By using the semi empirical equation proposed by Gilliland, calculate the diffusion coefficient for CO₂ in air at atmospheric pressure and 25°C.

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Step 13 a i Thermodynamics takes about equilibrium conservation of heat energy direction of heat flo... View the full answer