HPC LES & quasi-DNS of Complex Geometries Applied to Power Generation

Fluid-elastic instabilities, fatigue and wear inside steam generator tubes are a major concern for power generation industry. A major parametric CFD study of tube bundles seems worthwhile in view of the large potential savings worldwide, for coal power plants alone; Bouris et al. 2001. As experimental studies are limited in terms of level of detail and access inside densely packed arrays, predictions from fine numerical simulations (such as LES, DNS/quasi-DNS) are a useful complement. A highly complex flow pattern exists for such multiple tube configurations (in-line or staggered bundles) with peculiar flow behaviors such as asymmetry in pressure distributions and/or wake deflections. Thus, one should first focus on simpler configurations such as the flow over single or a few (tandem or side-by-side) cylinders in order to not only validate the approach, but also to understand the underlying flow physics better. Within the framework of power generation, the nuclear power generators have many different design configurations and variants which include highly complex channels and sub channels, offering axial-, cross- or mixed axial-cross-flow configurations. In the current discourse we present results from both the cross and axial flow configurations