Abstract:

For the purpose of researching the slug pneumatic conveying characteristics of gas-solids two phases flow，a 1∶1 improvement of test bench for the pneumatic conveying system in industry was conducted. Firstly，the flow modes of fly ash in conveying pipes was tested,then the conveying pressure and the mass flow rate of fly ash were tested,finally，the influence of main conveying gas flow rate，fluidizing gas flow rate and adjustment gas flow rate on the mass flow rate and solids-gas ratio was investigated. The test results indicated that the flow mode of the slug pneumatic conveying was mainly based on the slug-flow of dense phase，of which the slug-flow was 0.8—2.3 m long at the conveying speed of 2.8—11.3 m·s^-1. With the hyperbolic characteristics of conveying pressure and mass flow，the mass flow increased with increasing amount of gas. The main conveying gas played a leading role in the process，which had a monotonously rising parabolic relation with the mass flow rate of fly ash，as well as a convex parabolic relation with solids-gas ratio (first increased and then decreased). The research results would provide basic information for the engineering design，operation and theoretical study of the slug pneumatic conveying systems.