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Politecnico di Milano Department of Energy - School of Industrial Engineering Course Energy Systems LM prof. S. Consonni, E. Martelli, M. Romano - Academic Year 2014/15 Written Exam – Energy systems LM pag. 1 di 4 Written Exam 02 March 2015 - Problems - Time: 2 hours PLEASE NOTICE 1) Exam is open book, but computers and cell phones are NOT allowed. 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 sets. 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) The final grade is the sum of the points assigned to the solution of each problem plus a bonus of max 3 points. The bonus will be given based on whether the solution of each problem is complete, with clear details and explanations. FIRST NAME . . . . . . . . F A M I L Y NAME . .. Problem 1 (16 points) The steam cycle of a power plant features the following characteristics. • Steam turbine is fed with 120 ton/hr of steam at 90 bar, 520°C (stream 3) • Condensation pressure 0.08 bar (absolute) (stream 4 at condenser inlet, stream 1 at outlet) • Steam bleed from turbine for feedwater heating at 6 bar (stream 6). After being condensed and subcooled to 80°C in the FeedWater Heater (FWH), the condensate exiting the FWH (stream 7) is throttled to the condensing pressure and discharged to the condenser (stream 8) • Subcooled liquid at 34°C collected in the hot well at the bottom of the condenser (stream 1) is pumped to 130 bar (stream 2) by the feedwater pump and sent directy to the FeedWater Heater, where it is heated to 150°C (stream 5) • The…