Performance improvements of the recuperated gas turbine cycle using absorption inlet cooling and evaporative aftercooling

Abstract

An absorption inlet cooling system is introduced into the recuperated gas turbine cycle. The exhaust gases of the cycle are used to run the system. Five different layouts of the recuperated gas turbine cycle are presented. These include the effects of absorption inlet cooling, evaporative inlet cooling and evaporative cooling of compressor discharge (evaporative aftercooling), and the combined effect of absorption inlet cooling and evaporative aftercooling. A parametric study of the effect of pressure ratio, ambient temperature and relative humidity on the performance of all cycles is carried out. The results indicate that absorption inlet cooling could increase the efficiency of the recuperated cycle by up to 4 per cent, compared with 2.2 per cent for evaporative inlet cooling. Absorption inlet cooling with evaporative aftercooling could increase the optimum per efficiency of the recuperated cycle by up to 5 per cent and its maximum power by up to 65 per cent. Evaporative aftercooling reduces the impact of inlet cooling. Another parametric study of the effect of the turbine compressor inlet temperature ratio on the optimum pressure ratios indicated that cycles with evaporative aftercooling have higher optimum pressure ratios, which could be a function of the inlet temperature ratio and air temperature at the compressor outlet.