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Show Solution Methods Solution of Flow and Scalar Equations The discretized mass and momentum equations are solved in a segregated approach using a standard projection method -- the SIMPLE algorithm (Patankar and Spalding, 1972). The discrete momentum and pressure correction equations form systems of linear, algebraic equations. These systems are solved individually with an algebraic multi grid solver which is based on the work of Hutchinson and Raithby (1986) and Ruge and StUben (1987). Scalar transport equations are also solved with the algebraic multi grid method. Solution of Radiative Transport Equation The discrete ordinates form of the RTE is spatially discretized on the same mesh as the fluid mechanics equations. A radiation solution is found using the standard streaming technique of the discrete ordinates method (Fiveland, 1982, 1991). The S4 approximation was used for all cases presented in this paper. V ALIDA TION ACTIVITIES The Gas Research Institute has funded work, under GRI 5093-260-2729, to produce a document that can be used by model developers to validate natural gas combustion codes. Work started in 1994 to identify data that could be used. Although little data were found in the literature that included flow and combustion measurements in the detail needed by model developers, the work by Sayre, et al. (1994), did provide some of the needed data, and these data were selected as the baseline set. Initial natural gas combustion tests were completed in the Burner Engineering Research Laboratory (BERL) located at Sandia National Laboratories by an IFRF/Sandia/EER team (Sayre, et al., 1994). The furnace geometry (Sayre, et al., 1994; Forniciari, et aI., 1994) is shown in Figure 1. The furnace is vertically fired, consisting of a base plate (in which the burner is installed), five octagonal "spool" sections, and a conical furnace hood with a cylindrical exhaust duct The spool sections were constructed using refractory-lined panels for the hot-wall measurements. The furnace base, hood, and exhaust duct are lined with 4 |