Heat Transfer of Laminar Flames of Hydrogen+Oxygen and Methane+Oxygen

Mixtures of a fuel and pure oxygen are used in various industrial processes. Especially in processes where a high heat generation is needed, oxy-fuel combustion is commonly used. One of the processes where a high heat input is needed is the heating and melting of (quartz) glass for the production of lamps. For this purpose, hydrogen+oxygen and methane+oxygen flames in an impinging jet like configuration are often applied. A one-dimensional numerical study was initiated to study the heat transfer from laminar oxy-fuel flames to glass. In this paper, the heat transfer rate of a methane-oxygen flame is compared to the heat transfer rate of a hydrogen-oxygen flame. Thermodynamic and chemistry phenomena are taken into accoun

Flame Jet Properties of Bunsen-Type Flames

The flame jet width and flame jet velocity of the burnt gases of a premixedBunsen-type flame are important parameters to quantify the heat transfer rate ofthese flames.In this paper a simple expression is derived to estimate the resulting flame jetwidth and flame jet velocity of burnt gases of a free flame afterexpansion over the flame front for the special case of plug flow in and abovethe burner. The results of PIV experiments on three different flame types,having different oxygen concentrations, are presented. The model is validatedwith these measurements and shows good agreement. Deviations occur, however,when the curved flame front area of the flame tip is not negligible compared tothe total flame area

Heat transfer distribution for an impinging flame jet to a flat plate

Impinging flame jets are widely used in applications where high heat-transfer rates are needed, for instance in the glass industry. During the heating process of glass products, internal thermal stresses develop in the material due to temperature gradients. In order to avoid excessive thermal gradients as well as overheating of the hot spots, it is important to know and control the temperature distribution inside a heated glass product. Therefore, it is advantageous to know the relation describing the convective heat–flux distribution at the heated side of a glass product. In a previous work, we presented a heat–flux relation applicable for the hot spot of the target [M.J. Remie, G. Särner, M.F.G. Cremers, A. Omrane, K.R.A.M. Schreel, M. Aldén, L.P.H. de Goey, Extended heat-transfer relation for an impinging laminar flame jet to a flat plate, Int. J. Heat Mass Transfer, in press]. In this paper, we present an extension of this relation, which is applicable for larger radial distances from the hot spot