DESIGN AND TEST OF A NEW AXIAL COMPRESSOR FOR THE NUOVO PIGNONE HEAVY-DUTY GAS-TURBINES

This axial compressor design was primarily focused to increase the pow er rating of the current Nuovo Pignone PGT10 Heavy-Dirty gas turbine b y Iq percent. In addition, the new II-stage design favorably compares with the existing 17-stage compressor in terms of simplicity and cost. By scaling the flowpath and blade geometry, the new aerodynamic desig n can be applied to gas turbines with different power ratings as well. The reduction in the stage number was achieved primarily through the meridional flowpath redesign. The resulting higher blade peripheral sp eeds achieve larger stage pressure ratios without increasing the aerod ynamic loadings. Wide chord blades keep the overall length unchanged t hus assuring easy integration with other existing components. The comp ressor performance map was extensively checked over the speed range re quired for two-shaft gas turbines. The prototype unit was installed on a special PGT10 gas turbine setup, that permitted the control of pres sure? ratio independently from the turbine matching requirements. The flowpath instrumentation included strain gages, dynamic pressure trans ducers, and stator vane leading edge aerodynamic probes to determine i ndividual stage characteristics.;The general blading vibratory behavio r was proved fully satisfactory. With minor adjustments to the variabl e stator settings, the front stage aerodynamic matching was optimized and the design performance Mas achieved.