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This report presents results from a systematic study to establish whether CFD techniques are capable of predicting pressure drop in duct fittings including single elbow, close-coupled five-gore elbows having nominal diameters of 203 mm (8 in.) and 304.8 mm (12 in.) and turning radii r/D = 1.5. The close-coupled elbow combinations comprised either a Z-shape or a U-shape. In every instance the duct length separating the center points of the elbows was systematically varied. An experimental program was likewise conducted to verify the CFD predictions, and data from the measurements are included. Zero-length pressure loss coefficients were predicted, as well as the Reynolds Stress Model (RSM), and compared to experimental data. Two-equation turbulence models predicted incorrect trends when applied to flow in U- and Z-configuration ducts. However, the k-gamma and the Reynolds Stress Models (RSM) with enhanced wall treatment were generally able to correctly predict elbow loss coefficients with an error of less than 15%. None of the two-equation and RSM models could predict the experimental velocity profiles of Z- and U- configurations accurately.