(SSL Module Only) The Minimal Slurry Calculation method was developed for fully-stratified flow, but can be used as a conservative method for two-layer heterogeneous flow. The following data are required for the Minimal Calculation Method

• Temperature

• Solids concentration

• Density

• Sliding friction coefficient, μ_s

Horizontal pipes

The pressure drop in a given by the relationship given by Wilson, et al, 2006Wilson, K.C., G.R. Addie, A. Sellgren and R. Clift, Slurry Transport Using Centrifugal Pumps, 3rd Ed., published by Springer, 2006. , on page 116. As described in the discussion in the book, the coefficient 0.55 is based on sand or gravel sliding in steel pipe which has a coefficient of sliding friction, μ_s of 0.40. The equation then is modified with the ratio of the value entered on the Slurry Definition panel of Analysis Setup and becomes the following:

(1)

Where i_m is the dimensionless head gradient and V_m is the mean velocity based on the full diameter regardless of whether any solids collection in the bottom of the pipe has reduced the effective diameter. Note that when the Minimal Input option is selected in Analysis Setup on the Solids Definition panel there is no value entered for the d₅₀ or d₈₅ particle sizes in the Solids Definition panel and therefore the exponent M, V₅₀ and other parameters cannot be determined.