CURRENT - A Computer Code for Modeling Two-Dimensional, Chemically Reaccting, Low Mach Number Flows

Abstract

This report documents CURRENT, a computer code for modeling two-dimensional, chemically reacting, low Mach number flows including the effects of surface chemistry. CURRENT is a finite volume code based on the SIMPLER algorithm. Additional convergence acceleration for low Peclet number flows is provided using improved boundary condition coupling and preconditioned gradient methods. Gas-phase and surface chemistry is modeled using the CHEMKIN software libraries. The CURRENT user-interface has been designed to be compatible with the Sandia-developed mesh generator and post processor ANTIPASTO and the post processor TECPLOT. This report describes the theory behind the code and also serves as a user's manual. 314

SIERRA Low Mach Module: Fuego Theory Manual - Version 4.52

“…The level 1 turbulence model in FUEGO is the standard − turbulence model with constants and wall functions established for forced convection flows. The v2-f turbulence model is a modified − turbulence model [21] that has been implemented and evaluated recently for several flows without [235] and with [236] heat transfer in the Sandia research code CURRENT [237]. The v2-f model has been implemented in FUEGO recently as an unsupported feature.…”

Optimization strategies for complex engineering applications

“…A principal solution variable is associated with each physical equation and the linearization of the equation if performed with respect to the variable. The segregated approach is found most often in fluid mechanics code, such as CURRENT [12], where velocities are associated with momentum equations and temperature is associated with an energy equation. The individual linearizations can be combined to form the overall sensitivities required for the adjoint method, but the sensitivity coefficients are approximate so the gradients will be approximate.…”

“…The CURRENT [12] code uses a segregated solution approach. The continuity, momentum, and energy equations are solved solved at separate steps for the solution variables of pressure, velocity, and temperature.…”

“…The convective heat flux to the isothermal channel floor is calculated using CURRENT [12] fluid mechanics code and the ANTIPASTO [19] meshing code. The problem is exaggerated to provide good visual results by driving the reactor at a higher mass flow rate, thereby requiring a larger acceleration and slope-change to achieve flux uniformity.…”

Solution Algorithm for Low-Peclet-Number Reacting Flow

“…The CURRENT code is an extensive reformulation of the TEACH 11 code by Evans. 4,12 He recast the governing equations in terms of a generalized body-®tted co-ordinate system with multiple-block grids and implemented multicomponent transport with gas phase and surface phase chemical reactions.…”