A Parametric Study of Chat Cycle Performances: Thermodynamic and design Features

The CHAT (Cascade Humid Air Turbine) cycle introduction has recently been proposed for a more simple and profitable application of the humid air turbine. The very interesting performance announced for this plant has been evaluated in this paper, particular attention is devoted to the multi-stage evaporation process and its thermodynamic limits. A detailed thermodynamic analysis of the most important cycle parameters, like various pressure levels, fire temperatures and blade coolant bleeding can permit the evaluation of better plant performances. The results show a substantial agreement with other published data and they confirm the good efficiency and high specific power of the CHAT cycle. Considering the proposed compressor and turbine for the CHAT plant an off design simulation of the plant is also realized to estimate the real behaviour of turbomachinery components. Moreover this study is based on ESMS code already developed by the authors and the new components model (thermodynamic, design and off-design simulation) introduced for this work are presented.