The purpose of this research is to investigate various states of flow in the supercritical regime under the same hydraulic conditions and equal inlet flow rate, which is known as hysteretic behavior. The hysteretic behavior of supercritical flow that can occur in a channel near additional structures, including changes in the bed of the channel, is investigated experimentally and analytically. Two average diameters of channel bed materials with dimensions of 1.12 and 2 cm are used. The flow rates are in the range of 250–600 L/min. In the primary flow, the fluid flow is increased experimentally, while in the secondary flow the fluid flow decreases. The results show that by first increasing the flow rate and then decreasing it, different flow behaviors are observed for the same laboratory conditions: with increasing flow, the relative depth indicates that the flow is in the subcritical regime, whereas decreasing the flow demonstrates supercritical behavior (for similar conditions). Also, by increasing the average diameter of the material, the hysteretic behavior of the flow intensifies.
