Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Wall Temperature Influence On Confined Laminar Equidiffusional Jet Flames
Submission Author:
Ricardo Soares , RJ
Co-Authors:
Ricardo Soares, Albino Leiroz
Presenter: Albino Leiroz
doi://10.26678/ABCM.COBEM2023.COB2023-1801
Abstract
Non-premixed laminar jet flames are present in a wide variety of equipments and also used as building-blocks for turbulent reactive flow models. For studies on confined diffusion flames assuming infinitely fast global reactions and equal mass and heat diffusivities are restricted to adiabatic solid contours, thus limiting its applicability in many practical situations. The present work evaluates the effects of burner surrounding wall temperature effects in an axisymmetric confined laminar reactive flow using an extension of the classic Shvab-Zel’dovich formulation. The limiting case of the unity Lewis number is considered to isolate the surrounding wall temperature effects in the reactive flow. The governing equations are solved using the Finite Volume Method in a structured mesh. The WUDS (Weighted Upstream Differencing Scheme) is used for the discretization of the convective terms and the SIMPLEC (Semi-Implicit Method for Pressure Linked Equations-Consistent) method is employed for pressure-velocity coupling for the velocity field solution. Results are obtained for different wall temperatures, allowing for analysis of changes in the flow development and on flame height and width. Besides, results also show that axial evolution of the mean flow temperature and Nusselt number along the surrounding contour for the observed over-ventilated flames. A non-monotonic behavior of the axial mean flow temperature profiles is observed due to heat release from the combustion chemical reaction. Furthermore, by the influence of both wall heat flux and axial mean flow temperature profiles, discontinuities in the Nusselt number profiles along the surrounding contour are also observed.
Keywords
Wall Temperature Effects, Coflowing Jets, Laminar Diffusion Flames, Flame Sheet Model, Finite volume method
