Outer wall surface temperature data for catalytically supported thermal combustion systems with extremely high gas flow rates
Description
At the inlet, a fixed, flat velocity profile is used. This boundary condition fixes the convective component of the flux of species and energy, but the diffusive component depends on the gradient of the computed temperature or species fields. Symmetry boundary conditions are applied at the centerline between the two plates. At the exit, a fixed pressure is specified and far-field conditions are imposed for the rest of the variables. At the interface between the wall and the fluid, no-slip boundary condition is employed. The heat flux at the wall-fluid interface is computed using Fourier's law and continuity in temperature and heat flux links the fluid and solid phases. The left and right edges of the wall are assumed to be insulated. Newton's law of cooling is used at the outer edge of the wall. All internal heat transfer between the fluid and the wall is calculated by accounting explicitly for the convective and conductive heat transport in the model within the fluid and within the wall. The wall thermal conductivity is taken as an independent parameter to understand how important thermal management is. The mathematical formalism developed to describe transport phenomena and chemical kinetics is implemented into ANSYS FLUENT. The computer code and its usage are fully documented. More specifically, ANSYS FLUENT is applied to define the terms in the equations relating to conservation, thermodynamics, chemical production rates, and equation of state, and then combine the results to define the problem involving surface chemistry. To describe the surface reaction mechanisms in symbolic form, the following information is required, including the thermochemical properties of surface species in the surface phases, names of the surface species, site densities, names of all surface phases, Arrhenius rate coefficients, reaction descriptions, and any optional coverage parameters. Contributor: Junjie Chen, E-mail address: koncjj@gmail.com, ORCID: 0000-0002-5022-6863, Department of Energy and Power Engineering, School of Mechanical and Power Engineering, Henan Polytechnic University, 2000 Century Avenue, Jiaozuo, Henan, 454000, P.R. China
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Steps to reproduce
To solve the conservation equations, a segregated solution solver with an under-relaxation method is used. The segregated solver first solves the momentum equations, then solves the continuity equation, and updates the pressure and mass flow rate. The energy and species equations are subsequently solved and convergence is checked. The latter is monitored through both the values of the residuals of the conservation equations and the difference between subsequent iterations of the solution. The governing equations are discretized in space, and the second-order upwind discretization scheme is used. The pressure-based segregated algorithm is used with SIMPLE-type pressure-velocity coupling. The under-relaxation factors are reduced for all variables. The residuals decrease by at least six orders of magnitude. Overall heat and mass balances are achieved and the net imbalance is less than one percent of smallest flux through the domain boundaries. The solution converges when the residuals reach the specified tolerance and overall property conservation is satisfied.