The design approach for supercritical CO2 gas turbine

Abstract

Nowadays the engineers are paying a great interest in the development of power plants for electricity production with zero greenhouse gas emissions. Oxy-fuel combustion cycle is a promising technology requiring detailed turbomachine development. This study presents the results of preliminary flow path design of a supercritical carbon dioxide gas turbine. Initial working fluid parameters for the developed 350 MW turbine are 1150 °C and 300 bar. The turbine pressure ratio is equal to 10. The turbine flow path with a constant root diameter was chosen. Blade length of the first stage is 31 mm with a mean diameter of 969 mm. Blade length of the last stage is 169 mm with a mean diameter of 1040 mm. The convective blade cooling system was proposed. With an average cooling efficiency factor of 0.4, the coolant flow consumption is no more than 10% of the total flow of carbon dioxide to the turbine. The presence of heat transfer intensifiers in the blade internal channels determines the cooling depth up to 150 °C, which allows the use of well-mastered heat-resistant alloys in gas turbine construction.