3 Hands On

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HANDSON3 Thermorconomics Exercise1 ÉsÉotÉD Yet Set Éntot Gasifiera ÉsEzÉsÉde Ebe19MW Met.ua É 0,81 ReypeÉ980Es CHPb EzEaÉsÉoEdb Edb35H Metrb ÉEstÉ 0,56 Éz Metfb Ent5 0,50Ez Wholesystemath ÉsÉ7ÉsEatÉsÉoÉpatb Épath54MW Metyeah É3tÉhtÉftÉeayÉzÉ7 Metfath EatÉa Éz 940 The number of required auxiliary relations can be derived by subtracting the number of components and the number of flows entering/exiting the system. ÉsÉzÉsÉdia a LetZa a Ca C C E b É EatEatEat 2 7tZhi Can s b NauxMflouslamp72 5 5auxiliaryequationsarerequired 11 2,3 658,33EHNL 13 16 7la as up GMversion 15 1W'S 1W's 0,2778153Wh I651510 0,2778106Wh0,2778MWh 16J 0,2778kWh The cost structure of steam and electric power are derived substituting the exergy balance into the economic cost balance. It is important to remember that the cost structure can be given as a sum of 3 terms (as above calculate) Componenta EsEzEzÉsa uÉeZa Éztests C2 C1 aÉbetÉs Ze is EEEafter Componentb ÉzÉ7 EnÉsÉoÉnb EzC7É7Zb CuÉhtCsÉscoÉo aCINb GÉ2tGÉx a ÉzÉ7 Cp CyCs Inb InÉDibÉ6 ÉaÉs EFIES fit taffe2138 Design evaluation and optimization procedure aims at: - identifying critical processes or components in a given system, i.e. the components for which thermodynamic irreversibility affect the cost of useful products more than others; - suggesting possible way to optimize the costs of useful products, finding the optimal trade- offs between economic investment costs of components and their estimated economic costs of exergy destructions; Empmenta DCa 8,338,33ftp.t3600 so 8,332,08 45 55,42EkWh Componentb an GÉ2tÉ a 55,42kWh ÉztÉX Cp 55,42755,42355 1800 11525 t 1575 55,4255,42his 155,82EWh