In this paper, by adopting the continuous ring model and the perturbation analysis for free vibration, the authors showed the reason and the importance for the modes split phenomena and provided the qualitative relation between modes split and perturbation for the harmonic number of stiffness perturbation. Also through the modal analysis for forced vibration the authors showed possible ways to predict and prevent the worst case when blade will crack. That is, the harmonic number for stiffness distribution should be avoided to be twice the engine order.

A simple and convenient model to analyze the composition of the syngas has been implemented. We collect thermodynamic properties data from JANAF tables and Turns’ book. By regression analysis the Gibb’s energy functions of temperature were got. Through these functions, the equilibrium constants as functions of temperature can be deduced for the related chemical reaction in gasification process. With the equilibrium constants, the model to calculate the equilibrium composition for pure carbon gasification has been established. The model was improved from considering only isothermal reaction to including reaction heat balance and then finally with fully energy balance consideration. Since the model has been implemented on general software Excel, it will be very easy for users to apply in further study. Finally, we show how precise the estimation could be by doing comparison with early study and utilize this tool to analyze the heat balance for a specific IGCC cogeneration power plant.

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