A novel methodology has been used to design the layout of the tip cooling nozzles of a high pressure rotor blade turbine.
The methodology used is through a complete CAE approach, by means of a parametric CFD model which is run many times for the exploration of several designs by an optimizer. Hence the design is carried out automatically by parallel computations, with the optimization algorithms taking the decisions rather than the design engineer. The engineer instead takes decision regarding the physical settings of the CFD model to employ, the number and the extension of the geometrical parameters of the blade tip holes and the optimization algorithms to be employed.
The final design of the tip cooling geometry found by the optimizer proved to be better than the base design (which used mean values of all input parameters) and also better than the design proposed by an experienced heat transfer AVIO engineer, who used standard best practice methods.
Furthermore the large number of experiences gained by the several simulations run by the optimizer generated a virtual database of tip cooling configurations, allowing the designer to find laws, functions and correlation between input parameters and performance output, with a further and deeper insight on this specific design blade cooling problem. |
