HPC Simulation of Phase Change Fluid Flows Using a Geometric Reconstruction-free VOF Approach
Alexander Rattner, Georgia Institute of Technology
Accurate prediction of phase-change fluid-flow phenomena represents a major engineering challenge in the design of energy-intensive power-production and chemical-process equipment. Reliable analytical models have been developed for basic configurations, such as condensation, boiling, and absorption in plain tubes, smooth liquid films, and on flat surfaces. However, state-of-the-art enhanced heat transfer technology employs complex geometries that cannot be modeled analytically and are challenging to instrument for experimental investigations. Recent advances in computing and interconnect systems enable direct simulation of these processes using HPC resources.
While relatively mature tools are available for simulating adiabatic (no heat transfer) two-phase flows, methods for analyzing flows with phase change are still in their infancy. In the present work, a simplified first-principles-based phase-change model is developed, which forces interface-containing mesh cells to the equilibrium state. The operation on cells instead of complex interface surfaces enables the use of fast graph algorithms without geometric reconstruction. The model is validated for horizontal film condensation and converges to exact solutions with increasing mesh resolution. Agreement with established results is demonstrated for smooth and wavy falling-film condensation. In ongoing work, this approach is being extended to conduct highly parallelized simulations of more complex phase-change phenomena, including dropwise condensation, nucleate boiling, convective flow boiling, and vapor absorption.
Abstract Author(s): Alexander S Rattner, Srinivas Garimella