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Politecnico di Milano Department of Energy School of Industrial and Information Engineering Course Energy Systems LM proff. S. CONSONNI, E. MARTELLI, M. ROMANO - Academic Year 2019/20 Energy Systems LM - test of 25 June 2020 page 1 of 2 Written Exam of 25 June 2020 - Problems - Time: 2 hours PLEASE NOTICE 1) Exam is open book, but computers and cell phones are NOT all owed. Talking with colleagues and/or copying will lead to the immediate cancellation of the exam. 2) Answer clearly ONLY to the questions posed by the problem se ts. Even if correct, additional considerations and/or calculations will NOT be considered. 3) Fill this sheet with your name and return it together with your solutions. 4) Mark each sheet of the solution with your name and page number. 5) In addition to the points obtained for the solution of each problem, a bonus of max 3 points may be given based on whether the solution of each problem is complete, with clear details and explanations. Problem data depend on your person code according to the following two variables: X = sum of the numbers of your person code Y = sum of the first 4 numbers * sum of the last 4 numbers of your person code So, for instance, if the person code is 12345678  X = 36  Y = 10*26 = 260 INDICATE ON THE FIRST PAGE THE VALUES OF X AND Y DERIVING FROM YOUR PERSON CODE THAT YOU WILL USE IN THE EXAM Problem 1 (10 points, including Q1) A boiler with steam drum and co-current flow arrangement produces saturated steam at 4 bar starting from liquid water at 25°C and 4 bar. The heat source is a stream of hot gas from an industrial process at 10*X °C with flow rate Y kg/s and specific heat capacity 1.1 kJ/kgK. The minimum temperature difference in the boiler is 10 °C and the subcooling ΔT at the outlet of the economizer is zero.…