Some modern aspects of fluid mechanics

Selected aspects of current theoretical and experimental research in fluid mechanics are reviewed, with an emphasis on fundamental problems. Topics discussed include heuristic and axiomatic methods in the derivation of Navier-Stokes equations, the energetics of drag-associated dissipation, the resistance equation of Oswatitsch (1945), viscous potential flows, and the experimental realization of a moving wall (closely approximated by a spherical gas bubble rising through a resting fluid). Drawings, graphs, and a photograph are provided.