Application of conjugate heat transfer and fluid network analysis to improvement design of turbine blade with integrated cooling structures

Abstract

A combination of fluid network analysis method with conjugate heat transfer are applied to the improvement design of the integrated cooling structures in a high-performance turbine blade, coupled with the 3D viscous solver for the gas flow field. By comparison with the experimental results of open literatures, the methodology developed is numerically validated. For a high-pressure turbine rotor blade, it is used to rapidly predict and evaluate the aerodynamic and heat transfer performances of its integrated inner cooling structures. According to the computation results, three ways are definitely proposed for the improvement design, including the adjustment of the coolant flow mass entering into the front and rear cavities in a more appropriate flow mass ratio, the improvement of the turning geometries in serpentine channels to minimize the inner coolant flow resistance, and the adjustment of the local cooling structure dimension according to the high temperature region on outer surface of blade. Through the verification of the fully 3D conjugate heat transfer simulation for the fields of gas flow, solid blade and coolant flow, it shows that the maximum temperature on rotor blade surface is reduced obviously, the temperature distribution becomes more uniform after improvement, and the inlet parameters of cooling cavities are matched more reasonably. It is concluded that in this paper the fluid network combined with conjugate heat transfer significantly shortens the aerodynamic and heat transfer design cycle for the turbine blade with integrated cooling structures.

Conjugate heat transfer analysis of a rotor blade with coolant channels

“…Here, the momentum, continuity, and energy equations are resolved along with the turbulence equations for modeling the turbulence quantities. Most of the previous researchers 14 had successfully used the shear stress transport (SST) model over Reynolds averaged navier-stokes model for predicting heat transfer on a turbine airfoil. For pressure velocity coupling, SIMPLE algorithm is used.…”

“…This was attributed to the particular placement of film holes and outlets of the cooling flows. Peigang et al 14 reported a conjugate heat transfer study using integrated cooling systems in a high-performance turbine blade and suggested three ways for the improved design namely: (i) increasing coolant flow ratio, (ii) improving the turning of serpentine channels to minimize the resistance of inner coolant flow, and (iii) adjustment of the local cooling structure dimension according to the high-temperature region on the outer surface of the blade.…”