Impact of Aerodynamic Performance by the Heat Value of Fuel Change on the Turbine Cascade of Ground Heavy Duty Gas Turbine

In this paper the turbine cascade of the ground heavy duty gas turbine designed by GE company has been redesigned to adapt middle and low heat value fuel by one dimensional and quasi three-dimensional calculation and analysis. To change the heat value of fuel brings the change of flow mass, which leads to a change in aerodynamic performance. The results of the redesign show that the general parameters are in a reasonable range, and the redesign balances the load of stages, decreases the load of the third stage. The outlet flow is close to axial flow. In the first and second stages, the energy loss of middle and low heat value fuel turbine is lower than high heat value fuel turbine. Mach number at the outlet of the third stator is high, which results in the loss in the rotor of middle and low fuel turbine higher than high heat value fuel. The loss at endwall is high, which shows that the secondary loss is an important factor to impact the loss distribution along blade height.