The deposition of suspensions for uniform flow in convergent channels under the combined influences of inertia, viscous, gravity and electrostatic image forces were studied theoretically. A two dimensional, steady, incompressible, laminar flow with uniform velocity profile was assumed.
It was found that when the ratio of charge parameter to gravity parameter, Q/G, is greater than 5, the deposition is dominated by the electrostatic image force alone and that the gravity effect can be neglected. When the ratio of charge parameter to gravity parameter, Q/G, is less than 0.001, the image force can then be neglected. It was also observed that when the value of the inertia parameter S is less than 0.01, the inertia effect on the deposition can also be neglected.
Results under the influence of inertia, viscous, gravity and electrostatic image forces indicate that for a constant convergent channel angle and fixed inertia and gravity effect (less than 1), the deposition increases as the image force increases. If gravity is greater than 10, the deposition increases at the entrance and then decreases as the image force increases. The deposition decreases at the entrance region of the convergent channel as the convergent angle increases. The deposition then decreases as the axial displacement X increases. However, when Q is greater than 10, the deposition increases as the convergent angle increases. In all cases the deposition increases as the gravity effect increases.
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