The understanding of the flow characteristics and effect of gas-solid interactions in pneumatic risers is fundamental to investigate to ensure effective design cost-effective operation. Thus

to understand the effect of gas-solid interactions on the hydrodynamics of newly proposed conversing risers

this study mainly focused on predicting pressure drop in the dilute phase pneumatic conveying system. The experiments were conducted in a converging riser having a convergence angle of 0.2693°. Various solid particles such as sago

black mustard

and alumina have been considered to study the effect of particle sizes and density on the pressure drop. The experimental outcomes indicate that the total pressure drop increases with an increase in the solid density and gas mass flow rate. Moreover

smaller particle sizes are also increased the pressure drop. An empirical correlation is developed for the prediction of total pressure drop Δ

P

T

in converging pneumatic riser

via

dimensional analysis. All dependent variables such as particle and air density

drag force

acceleration due to gravity

the mass flow rate of air and particle

the diameter of particle and converging riser

the height of converging riser were considered to devel

op the empirical correlation. The established relationship is tested

and experimental data have been fitted for its validation. The estimated relative error of less than 0.05 proved the significance of the developed correlation. Hence

it can be stated that the established relationship is useful in studying the effects of various parameters on the pressure drop across the length of the conversing riser.