Session: 14-03: Internal Air System: Rim Seal, Clearances and Leakage Flow

Paper Number: 153915

Design Solutions for Decreasing Blade Tip Clearance Leakage Flow Using Thermomechanical Approach 

Reduction of labyrinth seal clearances over shrouded low pressure turbine blades is essential to achieve high module efficiencies, thereby lowering specific fuel consumption of aero gas turbine engines. Optimisation of tip seal clearance shall be conducted over a flight mission so that maximum efficiency benefit is attained at critical design points. In current study, the change in rotor tip seal leakage in different designs is examined with thermomechanical analysis transiently. Various design solutions are tried based on changing part joint type, stator part geometry, rotating part geometry and Secondary Air System (SAS) purge flow. These design solutions can be summarized as SAS purge flow from different locations to gain blockage effect, discourager from rotor and stator surfaces, shrouded NGV design and shroud assembly on casing and the effect of part mass change of both stator and rotor. The effect of various designs on rotor tip seal clearance is evaluated. The results, in terms of metal temperatures, SAS air use, clearance levels, module performance, manufacturing and assembly considerations are examined to reach the optimum design from a system level. Finite Element Analysis (FEA), Computational Fluid Dynamics (CFD) and 1D flow network analyses are used to obtain metal temperatures, understand pertinent flow physics and assess clearance levels. A brief summary is presented tabulating the all findings. Promising design solutions have shown that, it is possible to reduce rotor tip clearance by 25% compared to reference geometry. It has been observed that design options can improve turbine efficiency up to 1%.

Presenting Author: Güneş Ece Akalın Arıkan TUSAS ENGINE INDUSTRIES (TEI), INC.

Presenting Author Biography: In 2014, I graduated from Istanbul Technical University with a Bachelor of science High Honors' degree in mechanical engineering. In 2018, I graduated from Boğaziçi University with a Master of science in mechanical engineering. After graduate student researcher, I am working at TUSAS Engine Industry (TEI) more than 4 years as a lead design engineer in Whole Engine team. I am focused on Engine Clearances Design and analysis.

Authors:

Güneş Ece Akalın Arıkan TUSAS ENGINE INDUSTRIES (TEI), INC.
Ahmet Cihat Arıkan TUSAS ENGINE INDUSTRIES (TEI), INC.
Hakan Emiralioğlu TUSAS ENGINE INDUSTRIES (TEI), INC.
Erinç Erdem TUSAS ENGINE INDUSTRIES (TEI), INC.
Bedir İnci TUSAS ENGINE INDUSTRIES (TEI), INC.