Unsteady operating regimes of dredges

Conclusions

• 1. When operating suction pumps and plants prolonged transient processes occur due to changes in the spoil density. The operating regime during the transient process differs considerably from a steady regime, which must be taken into account when designing and operating spoil pumping plants.

• 2. The existing methods of calculating the operating regimes of spoil pumps and pipelines on the basis of the theory of steady regimes alone do not permit determining the transient regime. This regime is determined by the step functions of discharge, head, vacuum, and power, which are calculated on the basis of the transient-process equation.

• 3. In order to further improve manual and automatic control of dredges for the purpose of increasing their output it is necessary to determine the step functions, magnitude and duration of possible deviations in discharge, head, vacuum, and power in comparison with steady regimes. The same is necessary for selecting the equipment when designing suction dredges and pumping plants.