Example 3: A non-uniform stratified sand filter described in Table below is to be backwashed at the velocity of 2.5×10-2 m/s. Determine the depth of the expanded bed for the sand filter using the following assumptions: The bed depth = 0.65 m Sieve Porosity = 0.45 No. Particle diameter, mm f, Mass fraction Drag coefficient = 0.4 1.5 0.02 Shape factor 0.85. 14 1.2 0.10 Density of water = 1000 kg/m³ Viscosity 1 x 10-3 N.sec/m² 20 0.8 0.18 SG of the filter particles = 2.6. 25 0.7 0.35 30 0.6 0.17 35 0.5 0.14 40 0.4 0.04

Example 3: A non-uniform stratified sand filter described in Table below is to be backwashed at the velocity of 2.5×10-2 m/s. Determine the depth of the expanded bed for the sand filter using the following assumptions: The bed depth = 0.65 m Sieve Porosity = 0.45 No. Particle diameter, mm f, Mass fraction Drag coefficient = 0.4 1.5 0.02 Shape factor 0.85. 14 1.2 0.10 Density of water = 1000 kg/m³ Viscosity 1 x 10-3 N.sec/m² 20 0.8 0.18 SG of the filter particles = 2.6. 25 0.7 0.35 30 0.6 0.17 35 0.5 0.14 40 0.4 0.04

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter7: Permeability

Section: Chapter Questions

Problem 7.23P

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