The present work is focused on the investigation of heat transfer around a low pressure T106 turbine blade. The investigation was performed with the CFD computations which were validated against isothermal experimental measurements from literature. Detailed CFD computations were also performed for conditions including heat transfer for varying values of Reynolds number and turbulence intensity in order to assess their effect on average and local heat transfer coefficient on the low pressure turbine blade. The CFD analysis resulted in the development of new heat transfer correlations for the calculation of the average heat transfer coefficients taking into account the effect of Reynolds number and turbulence intensity. A comparison of these correlations in relation to literature available correlations for flat plate was performed in order to assess their deviation. The comparison indicated that for some cases a significant underestimation, of more than 10 %, of the average heat transfer coefficient can be presented resulting to an overestimation of the cooling air mass flow for turbine blade cooling applications and to a subsequent work loss and thermal efficiency decrease. Finally, the effect of this heat transfer coefficient underestimation on the efficiency and fuel consumption of a two-spool turbofan aero engine was calculated with Gas Turb11 performance analysis software. The results showed that through the use of more accurate heat transfer correlations an increase in core efficiency and a decrease in specific fuel consumption can be achieved.