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Politecnico di Milano Department of Energy - School of Industrial Engineering Course Energy Systems proff. S. Consonni, E. Martelli, M. Romano - Academic Year 2019-20 Energy Systems – Theoretical Questions – 21 January 2020 page 1 Written Exam 21 January 2020 Theoretical Questions ‐ Time: 1.00 h PLEASE NOTICE 1) Books, lecture notes, cell phones are strictly forbidden. Using them or talking with colleagues and/or copying will lead to the immediate invalidation of the exam. 2) Answer clearly ONLY to the questions. Even if correct, additional considerations will NOT contribute to the final grade – and you have NOT enough time! 3) Fill this sheet with your name and return it with your answers. 4) MARK EACH SHEET OF YOUR ANSWERS with YOUR NAME AND PAGE/SHEET NUMBER. 5) WRITING AND SHEET/PAGE SEQUENCE MUST BE LEFT TO RIGHT AS USED IN WESTERN COUNTRIES. 6) The final grade is the sum of the points assigned to the answer of each question plus a bonus of max 3 points. The bonus will be given based on completeness, clarity and details of the explanations. 7) Wherever possible, support your statements with clear drawings and/or graphical representation 8) ORGANIZE YOUR ANSWERS CLEARLY: ANSWER TO 1.a; ANSWER TO 1.b, ETC. FIRST NAME…………………………………….......……FAMILY NAME………………………………………………….. Question 1 (16 points) The steam cycle of a fossil fuel‐fired power plant features the following characteristics:  P evaporation 160 bar, P reheat 25 bar, P condensation 0.05 bar, T superheat and reheat 550°C  1 LP regenerator, 1 deaerator at 2 bar, 1 HP regenerator For the sake of simplicity, all pressure losses can be neglected A) Draw the cycle configuration. B) Draw the thermodynamic state diagram of the whole cycle on the Mollier (enthalpy‐entropy) diagram. C) In order to clarify the…