Geometric Decomposition and Structural Shape Modification for Turbomachinery Blades
Is Version Of
An efficient and precise method is presented for the generation of turbomachinery blade models in nominal configuration, i.e., the "cold-shape" given the blade geometry at operating conditions, i.e., the "hot-shape." The shape correction technique has two main components: a preprocessor that generates a plate finite element model of the hot-shape geometry, and postprocessor decomposes the hot-shape blade surface model into a mean camber surface and an associated set of thickness functions. A plate finite element mesh is generated on the resulting mean camber surface. The finite element model is used as input for specialized analysis software for cold-shape correction which provides displacements due to unloading the blade. The postprocessor constructs the nominal cold-shape blade model in two steps. First, the nodal deflections are applied to the hot-shape finite element model to generate a cold-shape mean camber surface. Then the original hot-shape thickness functions are applied to the cold-shape mean camber surface to generate characteristic blade section curves which are lofted to define the cold-shape blade model. Several examples of turbomachinery blades in their hot-shape and resulting geometry are presented to demonstrate the capabilities of the technique.
This is a conference proceeding from 20th Design Automation Conference 2 (1994): 397. Posted with permission.