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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 11 Feb. 2020 page 1 of 3 Written Exam of 11 February 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. FIRST NAME ....................................................... FAMILY NAME ..................................................... Problem 1 (18 points) A small-scale combined cycle features a single pressure heat recovery steam generator (HRSG) and an external deaerator fed by steam extracted from the steam turbine, as shown in Figure 1. The operating parameters of the combined cycle are reported in the following table. GT flue gases mass flow rate kg/s 190 Flue gas temperature at GT outlet °C 480 cP flue gases kJ/kg-K 1.07 Steam mass flow rate at turbine inlet (stream 1) kg/s 20 Steam temperature at turbine inlet (stream 1) °C 450 Steam pressure at turbine inlet (stream 1) bar 30 HRSG stack temperature °C 200 Isentropic eff. of HP steam turbine section (from stream 1 to SP1) - 0.9 Isentropic eff. of LP…