Performance Prediction of Axial Flow Two-Stage Turbine Based on Different Losses Models

The flow field in axial turbines is complex and three-dimensional. Therefore, experimental flow field is essential to determine the performance characteristics. However, such testing is always expensive and complex. Simulation of gas turbines is a simple way to reduce testing costs and complexity. The main objective of this paper is to make a detailed systematic analysis of two-stage, axial flow turbine by using of different loss models and a new suggested algorithm based on one-dimensional simulation. In one-dimensional modeling, the loss models have to be used to determine the entropy increase across each section of axial turbines stage at both the design and off-design conditions. The calculation used in this modeling is based on common thermodynamics and aerodynamics principles in a mean stream line analysis. Finally, in order to have a better understanding of the loss models behavior and verify the suggested algorithm accuracy, the analytical results from modeling were compared with experimental results and the comparison shows that good adaptation is obtained.