Seepage effects on settling velocity

• Main Author: Seow, Wei Kiong.
• Other Authors: Chiew Yee Meng
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Engineering::Civil engineering::Geotechnical
• Online Access: http://hdl.handle.net/10356/40943
• Institution: Nanyang Technological University

Settling is an important operation in many application such wastewater treatment, biological science and particle mechanism. However limited studies were done on possible seepage effect on the settling velocity of sediments. The objectives of this project were to have a better understanding of the settling path of the sphere, and to investigate the possible effects of the upward and downward seepage on the different zones of the settling motion of the particle and as well as it’s acceleration profile during the settling. Assumptions were made and dimensional analysis was carried out to establish a relationship between seepage effects on the deceleration/acceleration zone of the settling path of the sphere. The experiments were conducted in a vertical water column that was 0.4m long, 0.4m wide and 1.12m deep. Uniform plastic spherical particles of varying diameters (0.01m, 0.0795m, 0.0595cm and 0.052cm) and densities under different seepage inflow rates (0 m3/s, 1X10-4 m3/s, 1.5X10-4 m3/s and 2X10-4 m3/s) are used. Overall, the project’s objectives were met. A relationship had been established between the deceleration/acceleration zones of the sphere and the seepage effect. The result clearly shows that the acceleration profile of the sphere behaves differently in different zones of settling.