The objective of this project was the reduction of erosion in elbows (bends), in pneumatic transport systems, due to flow field modification. Air was to be injected into a bend, thus modifying the flow so that the eroding particles are kept from the surfaces. The goal of this effort was to achieve erosion rates less than those of blind-tees. A fluidized blind-tee and two different air injection bends were selected for detailed investigation. The detailed investigation demonstrated that the air injection bends significantly reduced erosion rates, but never developed an erosion rate less than that for a blind-tee. Although the air injection bends'erosion rates approached those for a blind-tee; technically the blind-tee represents a simpler system and consequently will probably remain the choice of engineers concerned with erosion of bends. 20 figs., 8 tabs.