Influence of flight shape on discharging profiles of granular material in rotary dryer

Abstract

In this work, Discrete Element Method (DEM) is used in order to calculate the motion of granular material in rotating dryers. We are particularly interested in analysing the effect of flight shape on the behaviour of spherical particles in the cross section of the dryer. We will be using two segments flights and three different profiles : a straight flight (180 • between both segments), an angled flight (with an angle of 120 •) and a rightangled flight (90 •). The results show that the profile of the flight affects significantly the motion of the particles in the cross section of the dryer. Changing the angle between the segment's flight, changes the flight loading and thus the material holdup which leads to different discharging profiles of the flight. For a right angled flight, the range of the discharge angle increases leading to a more uniformized cascade pattern in time and an enlarging of the area occupied by the curtains of particles. The specific durations (discharging time, falling time) are also determined and studied as a function of the flight shape.

An analysis of optimal segmented flight design in a rotary dryer

“…No other angle has been studied especially for discharging profile. Some works have been done numerically [14], but not for particles that were small enough to consider the material surface as flat. To validate our geometrical model and also the validity of the assumptions described previously in Section 2.8, we developed an experimental set-up to measure the volume of material carried up by two-segmented flights with different values of α 2 and ratio l 2 /l 1 .…”

“…Improving rotary dryer design to reduce power consumption and provide a better quality control of the final product, is of major interest to industries dealing with such equipments. For this reason, rotary dryers have been and are still widely studied theoretically [4][5][6][7][8], experimentally [8][9][10][11] and numerically [12][13][14]. Design of dryers is very important to control the drying performance.…”

A Novel Rotary Dryer Filled with Alumina Ceramic Beads for the Treatment of Industrial Wastewaters: Numerical Simulation and Experimental Study

“…The dust produced by ACBs grinding would be blown away by the drying air and leave the drum from the other side of the periphery. The dynamic behavior of the particles in a rotary drum largely depends on operational conditions [12][13][14], flow properties, and the physical properties of the material [15][16][17][18][19], as well as the geometric configuration of the drum [19,20]. Many efforts have been made to analyze the particulate material's dynamic behavior from various perspectives [17,[21][22][23][24][25].…”

Effect of baffle structure on the dynamic transportation behavior of s‐liked biomass fuels in a rotating drum

“…44 The correlation was expressed as Previous investigations on the behaviors of baffles within a rotary drum from different perspectives indicated that MRT and RTD had a significant influence on drying efficiency by changing holdup, first, and last loading baffles. 23,[45][46][47] In order to determine and design holdup, a numerical analysis was carried out on the proportion of gasborne and baffle-borne materials along the drum. 10,[48][49][50][51] However, publications almost focused on the MRT of particles and ignored RTD.…”