• Thermodynamic Analysis of Air Cooled Gas Turbine used in Marine Applications
• Author  :  K. Bala Prasad, V. Tara Chand, I. N. Niranjan Kumar, K. Ravindra and V. Naga Bhushana Rao
• Pages   :  32-39
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• Abstract

Failure of turbine blades before the anticipated working hours is a common problem in gas turbine units, due to hot corrosion and creep developed because of exposure of blades to high temperature gases over a prolonged period of time. To prevent such a failure, several blade cooling techniques have been suggested. In this paper an attempt is made to estimate the performance of marine gas turbine with internal convection air cooling for both stator and rotor blades of a gas generator turbine. The model evaluates the efficiency and specific work of simple open cycle air cooled gas turbine where expansion is considered as a continuous process with simultaneous heat and work extractions and which is influenced by the mixing losses of the coolant with the combustion gases. The mass flow rate of coolant air as a percentage of gas is also determined. Pumping work of coolant and heat transfer from the combustion gases to the coolant significantly influences the performance of the plant. The sensitivity of the efficiency and specific work to each key input parameter is reported. The results are also compared with the previously published results of open loop air cooled gas turbine model.

Keywords: Blade cooling – Open loop air cooling; Marine gas turbine; Efficiency; Specific work output; Coolant mass flow rate.

Article published in International Journal of Thermal Technologies, Vol.6,No.1 (March-2016)