Simulating Phase - Change Phenomena Using Gradient Augmented Level Set Approach
نویسندگان
چکیده
A sharp interface capturing approach is presented for two-phase flow simulations with phase change. The Gradient Augmented Level Set (GALS) method is coupled with the two-phase momentum and energy conservation equations to advect the liquid-gas interface and predict heat transfer with phase change. The Ghost Fluid Method (GFM) is adopted to discretize the advection and diffusion terms for velocity in computational cells located in the interfacial region. Furthermore, the GFM is also employed to treat the discontinuity in the stress tensor, velocity, and temperature gradient across the interface yielding a more accurate treatment in handling interfacial jump conditions. Thermal convection and diffusion terms are approximated by explicitly identifying the interface location, resulting in a sharp treatment for the energy solution. This sharp treatment is extended in estimating the interfacial mass transfer rate. At the computational cell, an n-cubic Hermite interpolation scheme is employed to describe the interface location, which is locally fourth-order accurate. This extent of subgrid level description provides an accurate methodology for treating the various interfacial processes with a high degree of sharpness. The ability to predict the interface and temperature evolutions accurately is illustrated by comparing numerical results with existing 1D to 3D analytical solutions. Corresponding author: [email protected] ILASS Americas 28th Annual Conference on Liquid Atomization and Spray Systems, Dearborn, MI, May 2016
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