관 내 물-토사 혼합물의 이상유동 해석

Abstract

Torrential rainfall in Korea causes the large amount of water and soil mixture flow into drainage pipes. Soil in the mixture is sedimented in drainage pipes and frequently blocks the pipes, results in flooding in a city. In the present study, the effects of inlet velocity, size of soil particle, and volume concentration of soil in the soil and water mixture on the flow characteristics and the soil distribution inside the pipe were numerically investigated by using the two-phase mixture model. The horizontally located pipe, whose length and diameter are 10 m and 0.6 m, was used in this simulation. With increase of inlet mixture velocity, velocity at the upper part of the tube is higher than that at lower part by 14.9%, and the volume fraction of soil from bottom to 0.2 m of tube decreased subsequently by 4.6%. The distribution of mixture velocity and soil volume fraction is getting uniform with increase of the inlet volume fraction of the soil in the mixture. With increase of size of the soil particle, the soil concentration increased subsequently by 6.6% from bottom to 0.2 m of the pipe, which make significant distortions in velocity distribution in tube.