| 1/00 | Influencing the flow of fluids |
| 1/02 | Influencing the flow of fluids in pipes or conduits |
| 1/04 | Influencing the flow of fluids in pipes or conduits Arrangements of guide vanes in pipe elbows or duct bends; Construction of pipe conduit elements or elbows with respect to flow, specially for reducing losses of flow |
| 1/06 | Influencing the flow of fluids in pipes or conduits by influencing the boundary layer |
| 1/08 | Influencing the flow of fluids of jets leaving an orifice (nozzles or outlets with means for mechanically breaking-up or deflecting the jet B05B, e.g. B05B 1/26) |
| 1/10 | Influencing the flow of fluids around bodies of solid material |
| 1/12 | Influencing the flow of fluids around bodies of solid material by influencing the boundary layer |
| 1/14 | Influencing the flow of fluids Diverting flow into alternative channels (in hydraulic engineering E02B) |