Computed Effect of Varying Tip Clearance and Axial Gap on Gas Turbine Stage Performance Part (I): (Steady Flow)

Wael M Elwan, Mohamed Raafat Shaalan, Mofreh M Nassief, Mohamed H. Gobran


It is desirable to further increase the efficiency of turbo-machines.  In axial flow gas turbine, imprecise axial gap and tip clearance are two significant sources of inefficiency.  This work investigates the effect of change in parameters such as axial gap and tip clearance on axial flow gas turbine used in power generation. Different combinations of axial gap and tip clearance have been tested to analyze the performance of the turbine.  It is revealed that the axial gap of 18.5% of axial chord and 2.4% tip clearance of blade height is the optimum set value for the maximum performance


Axial gap Tip clearance Efficiency Axial-Turbine

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