Analysis of the influence of cooling hole arrangement on the protection of a gas turbine combustor liner

Numerical investigations of an industrial gas turbine combustor were conducted in this paper. The studied combustion chamber has a high degree of geometrical complexity related to the injection system as well as the cooling system which consists of thousands of small holes (about 3390 holes) bored on the liner walls. The main aim of this study was to propose modifications into the liner cooling system that can enhance the protection of this critical component. The calculations were carried out using the industrial CFD code fluent 6.3. It was shown that the addition of rows of cooling holes in the primary zone of the liner leads to a reduction of the maximum liner metal temperature of 33%. Nevertheless, this modification causes an increase of the maximum gas temperature at the outlet of the combustion chamber of 12% which could be harmful to the turbine vanes. It was also shown that this increase can be controlled by the suppression of rows of cooling holes in the dilution zone.