1. The simulations were run on an IBM 370-3033 computer operating under the Conversational Monitor System, (CMS). A non-uniform 39 by 39 grid was used after grid-independence tests. The calculation domain was extended downstream of the region of interest a sufficient distance to ensure that the imposed exit boundary condition of negligible gradient of independent variable i n the streamwise (axial) direction was satisfied. TWO positions for the downstream boundary plane were tried, 0.8 and 1.0 meter from the flameholder. A t the greater distance a 35 by 39 mesh was used rather than the 39 by 39 used at the closer distance. The calculated flow field did not change between these two conditions. Calculations were therefore performed out to 0.8 meter using the denser grid; this distance i s over five times the distance of the annular air-jet stagnation point from the flameholder. For the grid independence tests, the effect of grid-densing on the location o f the stagnation points was examined. The 39 by 39 mesh given i n Figure 2 was determined to be satisfactory. The axisynetric calculations were made for one-half of the combustor.
2. The stagnation points and recirculation strengths shown i n Figures 5-9 inclusive, were obtained from LDV measurements of centerline axial velocities for a range of a i r and fuel flow rates. In addition, measurements were available for the root mean square value of axial fluctuating velocity on the centerline. These values enable some of the region imnediately downstream of the aft-stagnation point t o be examined.
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