LIFE PREDICTION OF TURBINE BLADES BY COMPUTER MODELING

THE CASTING PROCESS PRODUCES FLAWS OF VARIOUS TYPES AND SIZES IN TURBINE BLADES. EACH FLAW POTENTIALLY DEGRADES THE LIFE OF THE BLADE, BUT FOR ECONOMIC REASONS MANY INITIAL FLAW CLASSES ARE PERMITTED ON THE BASIS OF ACCEPTANCE CRITERIA DEVELOPED EMPIRICALLY BY ENGINE MANUFACTURERS. THE PROBLEM WITH THIS APPROACH IS THAT IT REQUIRES DATA OBTAINED FROM EXPERIENCE. IT CANNOT PREDICT BLADE LIFE IN A NEW ENGINE. MOREOVER, MANY BLADES CONTAINING A CHARACTERISTIC FLAWS CAN BE IN USE BEFORE SUCH A FLAW IS FOUND TO REDUCE SUBSTANTIALLY EXPECTED LIFE. WE PROPOSE TO CREATE A HIGHLY INTERACTIVE, COMPUTER-AIDED DESIGN SYSTEM TO SIMULATE THE PERFORMANCE OF A BLADE CONTAINING SPECIFIC FLAWS AND FLAW SIZES AT ARBITRARY LOCATIONS. THE SYSTEM WILL HAVE THE FOLLOWING INNOVATIVE FEATURES: SIMULATION BASED ON A TRUE GEOMETRIC REPRESENTATION OF THE BLADE VIA SOLID MODELING. A SOPHISTICATED, TOPOLOGY-BASED DATA STRUCTURE TO SUPPORT LINKAGE TO THE SOLID MODEL, FAST INTERACTION, AND ACCURATE REPRESENTATION OF EVOLVING FLAW SHAPES. THE ABILITY TO SPECIFY FLAWS TO ARBITRARY SHAPE, INCLUDING NON-PLANAR, SIZE, AND ORIENTATION AT ARBITRARY LOCATIONS IN THE GEOMETRIC MODEL. AUTOMATIC LOCAL REMESHING TO SIMULATE FLAW GROWTH. MODUALR ENCAPSULATION OF FRACTURE MECHANICS THEORIES AND GROWTH-RATE MODELS FOR PREDICTING THE EVOLUTION OF A FLAW. STATE-FO-THE-ART TECHNIQUES FOR SCIENTIFIC VISUALIZATION VIA COMPUTER GRAPHICS.