Dense-phase momentum balance

Dense-phase momentum balance effective particle weight in unit dense-phase volume is partially supported by the dense-phase fluid flow, and the rest is supported by the bypassing dilute phase fluid flow,... 

The pseudo-homogeneous or dusty-gas model very small particle Stokes number and limited polydispersity (momentum-balance equation only for the continuous phase if the system is dilute or for the mixture of continuous and disperse phases if the system is dense). 

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