Fluent Melting and Solidification Essay Example for Free

Fluent Melting and Solidification set ab kayoed8.1 Overview of Phase Change Modeling in silvernFLUENT can be used to lap up uid ow problems involving bodchange taking place at one temperature e.g., in pure metals or everywhere a range of temperature e.g., in binary alloys. Instead of explicitly tracking the semiliquid-solid front as the form change occurs, which requires a moving mesh methodology, an enthalpy-porosity formulation is used where the ow and enthalpy equations are solved with senseless source terms on the xed grid. Marangoni shear, due to the variation of surface tension with temperature, is important in galore(postnominal) industrial uid ow situations involving phase change. The phase change model in FLUENT provides the ability to specify the Marangoni side at a sloping surface, as headspring as an arbitrary shear at a boundary coinciding with one of the curvilinear grid lines. The model also allows you to specify the convective hotness transfer, radiati on, and heat ux at a wall as piecewise linear pro les, polynomials, or harmonic functions. FLUENT provides the pastime phase change modeling options Calculation of liquid-solid phase change in pure metals as well as in binary alloys. Modeling of continuous casting processes i.e., pulling of solid material out of the domain.Chapter 8 Phase Change Simulations aptitude to specify an arbitrary shear at a curved boundary as a piecewise linear pro le or polynomial in terms of one of the Cartesian coordinates. Modeling of Marangoni convection due to the variation of surface tension with temperature. Modeling of the thermic contact resistance between frozen material and the wall e.g., due to an air gap. Ability to patch a momentum source in each Cartesian direction and or a heat source to simulate magnetic force elds or heat generation in the domain, for standard. Display and patching of latent heat content, pull velocities in continuous casting and other applicable variables.These mode ling capabilities allow FLUENT to simulate a wide range of phase change problems including melting, solidi cation, watch crystal growth and continuous casting. The physical equations used for these phase change calculations are described in the by-line sections. Limitations of the As mentioned above, the phase change formulation in FLUENT Phase Change can be used to model the melting freezing of pure materials, as Model well as alloys. The liquid fraction versus temperature alliance used in FLUENT is the lever rulei.e., a linear relationship Equation 8.2-3. Other relationships are possible 124 , but not available in FLUENT. The following FLUENT features cannot be used in conjunction with the phase change model Radiation Combustion Speci ed periodic mass ow Cylindrical velocitiesOverview of Phase In order for you to enable the phase change model, the button equaChange Modeling tion must be active. You are then required to supply additional Procedures physical constants pertaining to the phase change problem liquidus and solidus temperature, latent heat of freezing, etc.. You may invoke one of the deepen boundary conditions that are available c Fluent Inc. May 10, 1997