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Politecnico di Milano School of Industrial and Information Engineering Exam of Heat and Mass Transfer MSc in Energy Engineering November 18th 2015 Family Name............................................................First Name.................................................. Identification number............................................ SCORE P1 - ................ / 9 P2 - ................ / 6 D1 - ................ / 5 D2 - ................ / 5 D3 - ................ / 5 OVERALL ................ /30 Test time span is 2 hours and 30 minutes. You can withdraw any time except during the last 10 minutes. Use of textbooks, notes, notebooks, tablet PCs and smartphones is not allowed. At the end, the teacher collects the class-tests. It is mandatory to hand in the foolscap sheets and this paper. The maximum score is 30/30 and, for each problem, it is equally assigned to the formal and numerical solution, respectively. After collection, the solution is shared and after a few minutes you are individually asked if you require the test correction (by default tests are not corrected). No penalty for scores greater than or equal to 10/30. Problem 1 score 9/30 A 5-mm thick, square, aluminum plate of side L=50 cm is attached through the bottom surface on a plane heater supplying a uniform heat flux q0=1500 W/m2, while its top surface is exposed to an ambient airstream flowing parallel to the plate at a temperature of 20 °C with a velocity U=5 m/s. The windward border of the plate is kept to a temperature To=50 °C, whereas the heat loss from all the other borders can be neglected. Assuming approximate one-dimensional heat conduction along the plate (parallel to the airstream), determine: 1. the analytic expression of the temperature distribution along the plate; 2. the maximum…