Abstract
Gravity currents are enough widespread and can reach catastrophic proportions.
It is still poorly understood features of the motion of the gravity current motion with the active mass transfer with the bottom sediments. In addition, it is difficult reliable quantitative estimates of the mass involved in the movement and carried down the slope sediments. An important goal is the development of physics catastrophically strong turbidity currents, especially in their head.
In this work, a laboratory simulation of gravity current along the bottom using the active mass transfer from the bottom sediments, as a model for sediment used polystyrene, with a density of 1.08 g/cm3, a lightweight bottom sediment was used because it is easy to make turbid, leading to maximize current mass transfer with the bottom sediments.
The experiment proved that the current’s motion down the slope has a constant speed, and the geometric dimensions of the current does not undergo a change in scale deviation from a mean. The overall strength of the resistance to flow can be divided into the power of resistance associated with the external environment, the strength of bottom friction and the force associated with involvement in the current bottom sediments. It makes sense to make further clarifications. A particle of sediments has velocity equel zero, when it is captured by current. After the capture of the particle it is accelerated to a speed of current. By the law of conservation of momentum current must to "slow down". Therefore, every act of taking a particles by current is accompanied by its inhibition.
During the experiments, it was found that the greatest braking force is the force associated with involvement in the movement of new sediment approximately 80% of gravity force. Accounting for all three forces gives a good agreement between experimental and theoretical results.
