3 Analysis of diverse heat recovery steam cycles Report A

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Course of Energy Conversion A 2014/2015 Prof. G. Valenti _________________________________________________ 3rd project Diverse Heat recovery steam cycles  Index: 1. Introduction; 2. 1-level combined cycle analysis 3. 2-levels combined cycle analysis 4. 3-levels with reheating combined cycle analysis 1. Introduction The aim of the project is to compare, with respect to the previous project, different possible configurations of the heat recovery steam generator in a combined cycle plant, at fixed gas turbines conditions. The plant is in fact optimized to work under the constraints of mass flow rate, power generated (and hence the first law efficiency) and exhaust outlet temperature of the gas turbine. Therefore, for the gas turbine we will take those assumptions, with respect to the constraints (highlighted in green): Simple Cycle parameters inlet mass flow rate 649,35 kg/s compression ratio 20 - TIT 1299 °C Texhausts 546,7 °C Net power 235,65 MW plant efficiency 0,338 - All the values listed here will be constant through the analysis of the diverse plant configurations. Notice that the mass flow rate is computed in order to grant the same power of the plant and the same exhaust mass flow rate to the heat recovery steam generator of the project 2. The quantities considered have been adjusted in order to have the most similar plant configuration as possible. 2. 1-level combined cycle analysis The first case we will take in account is the configuration that follows: # Despite the presence of the condensate removal line in the scheme, we will not consider this operation (so the mass flow rate will be considered equal to zero). The plant is in the exact same configuration as the one treated in the previous project, hence we will take the evaporation pressure at the steam…