Turbine blade cooling by air using different methods

الملخص EN

The determination of temperature distribution within a turbine blade is important in regards to avoid excessive high metal temperatures and temperature gradients.

The prediction of temperature distribution was achieved through the use of the finite difference technique, developed to solve the problem with the transformation and grid generation techniques.

Steady-state two-dimensional conduction heat transfer equation was applied to the internal nodes in mesh to get the temperature distribution, where at the surface nodes (outer, inner), forced convection heat transfer equation was applied.

The solution of the problem was established using computer program, which serves to solve the equations by using Gauss-Siedel iterative method.

In the present study, three cases are used for thermal analyses of the blade, which requires the specification of external and internal boundary conditions.

It is also found from the results obtained that the best cooling method to the turbine blade have been obtained for the third case when the blade cooled by impingement and film cooling method.

It was found in the film cooled blade that the blade temperature decreases about (170 K) cooler than the blade cooled without the film cooling method.

The results of thermal analyses obtained were compared with the finite element results.

The comparison shows that the finite difference results give a good agreement with the finite element results with a small difference was calculated to be (3.5 %) as maximum value and it fall to (0%) in most regions.