4 Advanced steam cycles Text

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COURSE OF ENERGY CONVERSION A 2015/2016 Prof. G. Valenti 4th Project Comparison of advanced steam cycles The present project aims at calculating the performance of diverse steam cycle configurations throughout the use of the research software CicVap. Consider the Ultra-SuperCritical (USC) plant as a reference p lant, namely configuration A; it is characterised by the following main features (as far as the other paramete rs are concerned, make reference to the attached tables): Configuration A - Superheater outlet mass flow rate: 1˙850˙000 kg/h - Superheater outlet steam pressure: 270 bar - n reheaters: 1 - n preheaters (deaerator included): 8 (4 low pressure, 4 high pressure) - n intermediate-pressure two-flow rotors: 2 - n low-pressure two-flow rotors: 4 - last stage blading: 33.5 inches – mean diameter 99.5 inches - steam temperatures: 580C / 580C - condensing pressure: 0.05 bar - fuel: coal - exhaust gases stack temperature: 150 C - O2 concentration in exhaust gases at the stack: 5% - economizer water inlet temperature: ~ 315 C Furthermore, consider other cycle configurations that differ from configuration A by the following characteristics (all the parameters which have not been reported remain equal to the former case A): Configuration B - fuel: natural gas - exhaust gases stack temperature: 120 C - stack O2 concentration in exhausts: 2.5% Configuration E - n regenerators: 4 (2 LP deaerator included, 2 HP) - economizer water inlet temperature: ~ 280 C Configuration C - condensing pressure: 0.1 bar Configuration F - n reheaters: 2 - steam temperatures: 580°C/580°C/580°C Configuration D - steam temperatures: 640C / 640C The water temperature increase during the regeneration process is assumed to be equally divided among all the regenerators for all the…