A 3-cm thick slab which can be modelled as a plane wall of thermal conductivity k = 30 W/m·K generates heat uniformly at egen = 5 × 106 W/m3. As shown in the figure below, it is sheathed on both...

A 3-cm thick slab which can be modelled as a plane wall of thermal conductivity k = 30 W/m·K generates heat uniformly at egen = 5 × 106 W/m3. As shown in the figure below, it is

sheathed on both sides by carbon-silicon steel1 sheets 1 cm thick and fitted with wide longitudinal fins of the same material of dimensions 2 cm in length and 1 mm in thickness which are spaced 1 cm apart on centres. The outside air temperature is T∞ = 20°C. If the temperature of the slab should not exceed 400°C, what is the minimum allowable external convective heat transfer coefficient h? State all assumptions made. White Question 2.81, Solution 2.71

2 NANYANG TECHNOLOGICAL UNIVERSITY School of Mechanical and Aerospace Engineering Session 2020 - 2021, Semester 1 MA3003 HEAT TRANSFER Homework 3 Given on Monday, 14 September 2020. Submission Deadline: Sunday, 20 September 2020, 23:59 h Instructions: Please submit your handwritten solution in PDF format into the “Submission of Homework” folder of your Tutorial Group NTULearn course site by Sunday 20 September 2020, 23:59 h. Use the cover page document given in the “Content folder” as the first two pages of your submission and write your full name on the right-hand corner of every page of your handwritten solution. Homework Question: A 3-cm thick slab which can be modelled as a plane wall of thermal conductivity k = 30 W/m·K generates heat uniformly at gene = 5 × 106 W/m3. As shown in the figure below, it is sheathed on both sides by carbon-silicon steel1 sheets 1 cm thick and fitted with wide longitudinal fins of the same material of dimensions 2 cm in length and 1 mm in thickness which are spaced 1 cm apart on centres. The outside air temperature is T∞ = 20°C. If the temperature of the slab should not exceed 400°C, what is the minimum allowable external convective heat transfer coefficient h? State all assumptions made. White Question 2.81, Solution 2.71 Homework 3 - MA3003-Sem 1 2020-2021 (updated on Monday, 24 August 2020) 1 Carbon-silicon composition: Mn ≤ 1%, 0.1% < si ≤ 0.6%. students should refer to table a-3 of the textbook for the appropriate thermal conductivity value. steel gene t∞ t∞ 3 cm 2 cm 2 cm 1 cm 1 cm mac k = 51.9 w/m.k at 300k k(steel) = 47.973� si="" ≤="" 0.6%.="" students="" should="" refer="" to="" table="" a-3="" of="" the="" textbook="" for="" the="" appropriate="" thermal="" conductivity="" value.="" steel="" gene="" t∞="" t∞="" 3="" cm="" 2="" cm="" 2="" cm="" 1="" cm="" 1="" cm="" mac="" k="51.9" w/m.k="" at="" 300k="" k(steel)="">