Steady Flow over an Obstacle

Abstract

A classification scheme for the regimes of steady flow over a fixed two‐dimensional obstacle is developed and tested experimentally. The results are compared with those derived from towing tank experiments. The two approaches differ, since the towing tank experiments do not always reach steady state. However, both approaches predict that two stable states may exist for the same external conditions. The existence of a hysteresis loop is demonstrated experimentally, but its extent is not as large as predicted. This discrepancy occurs because the theory implicitly assumes that the obstacle and any hydraulic jumps in the flow are of negligible length.