scholarly journals Coupled CFD-DEM Simulation of Seed Flow in an Air Seeder Distributor Tube

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1597
Author(s):  
Leno Guzman ◽  
Ying Chen ◽  
Hubert Landry
Keyword(s):  
Contact Force ◽  
Horizontal Tube ◽  
Solid Loading ◽  
Discrete Element Modeling ◽  
Pneumatic Conveying ◽  
Dynamic Features ◽  
Air Velocity ◽  
Dem Simulation ◽  
Field Peas ◽  
Loading Ratio

Air seeding equipment consists of various machine components that rely on pneumatic conveying of seeds (granular material) for its operation. However, studying air seeder dynamic features in detail is difficult through experimental measurements. A simulation was performed to study seed motion in a horizontal tube section of an air seeder distributor system. The simulation incorporated two-way coupling between discrete element modeling (DEM) and computational fluid dynamics (CFD). Simulated particles were assigned material properties corresponding to field peas. Air velocity was assigned values of 10, 15, 20, and 25 m/s. The solid loading ratio (SLR) in this study included values between 0.5 and 3 to describe typical seed metering rates used in air seeding. The different pneumatic conveying conditions were studied to determine their overall effect on the average seed velocity and seed contact force. The simulation was validated through the comparison of average seed velocity data from the literature and current pneumatic conveying theory. The effect of SLR on the average seed velocity was found to be not significant for the simulated SLR values. The CFD-DEM simulation was able to capture seed collisions between seeds and the surrounding boundaries. The seed contact force increased with the air velocity, and the number of seed collisions increased with the SLR.

Influence of Fluidizing Velocity on Fluidized Powder Conveying in a Horizontal Rectangular Channel

2011 ◽  
Author(s):  
Koichiro Ogata ◽  
Tomoya Furukawa ◽  
Yusuke Yamamoto
Keyword(s):  
Particle Density ◽  
Rectangular Channel ◽  
Porous Membrane ◽  
Horizontal Channel ◽  
Solid Loading ◽  
Pneumatic Conveying ◽  
Bed Height ◽  
Loading Ratio ◽  
Minimum Fluidizing Velocity ◽  
Conveying System

This study experimentally investigated the high dense pneumatic conveying of glass beads in a horizontal rectangular channel using the fluidizing air. The powder used belongs to Geldart A particle, where the mean diameter is 53 μm, the particle density is 2523kg/m3 and the minimum fluidizing velocity is 4.329mm/s. The fluidized powder conveying system consists of a powder supply hopper, a horizontal rectangular channel at the side of hopper and a receiving tank. The powder was fluidized by air through the porous membrane at the bottom of hopper and horizontal channel. Then, this system could be transported the fluidized powder toward the horizontal direction. In this study, the mass of transported powder, the bed height of powder in a hopper and the supply air pressure were measured when the fluidizing velocities at the bottom of hopper and horizontal channel were changed. The mass of transported powder with the fluidizing air to the bottom of hopper multiplied rapidly when the fluidizing velocity at the bottom of horizontal channel was larger than the minimum fluidizing velocity. Therefore, the fluidizing air at the bottom of hopper and horizontal channel was important to obtain smooth powder conveying on this system. Also, the mass flow rate of powder and the solid loading ratio were estimated from the mass of transported powder against the elapsed time. As the result, the solid loading ratio has taken a one peak when the fluidizing velocity at the bottom of channel was larger than the minimum fluidizing velocity. It was found from the analyzed solid loading ratio that the high dense powder conveying was possible in this system.

Simulation of countercurrent gas–solid heat exchanger: Effect of solid loading ratio and particle size

2007 ◽  
Vol 27 (8-9) ◽  
pp. 1345-1351 ◽  
Author(s):  
K.S. Rajan ◽  
S.N. Srivastava ◽  
B. Pitchumani ◽  
B. Mohanty
Keyword(s):  
Particle Size ◽  
Heat Exchanger ◽  
Solid Loading ◽  
Loading Ratio

Computation of flow and heat transfer in horizontal gas–solid flows through an adiabatic pipe

2020 ◽  
pp. 095440622093631
Author(s):  
Brundaban Patro ◽  
Kiran K Kupireddi ◽  
Jaya K Devanuri
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Nusselt Number ◽  
Pressure Drop ◽  
Solid Loading ◽  
Gas Velocity ◽  
Two Phase ◽  
Flow And Heat Transfer ◽  
Loading Ratio ◽  
Solid Temperature

The current paper deals with the studies of heat transfer and pressure drop through a horizontal, adiabatic pipe, having gas–solid flows. The inlet air temperature is 443 K, whereas the inlet solid temperature is 308 K. The numerical results are compared with the benchmark experimental data and are agreed satisfactorily. The influences of solid loading ratio, solid diameter and gas velocity on Nusselt number and pressure drop have been studied. The Nusselt number decreases and the pressure drop increases with an increase in the solid diameter. The Nusselt number decreases with an increase in the solid loading ratio at a lower solid diameter of 100 µm. However, at a higher value of solid diameter of 200 µm, the Nusselt number first decreases up to a specific solid loading ratio, and after that, it increases. The pressure drop results show different behaviours with the solid loading ratio. Both the Nusselt number and pressure drop increase with the gas velocity. Finally, a correlation is generated to calculate the two-phase Nusselt number.

DEM simulation of particle attrition in dilute-phase pneumatic conveying

2010 ◽  
Vol 13 (2) ◽  
pp. 175-181 ◽  
Author(s):  
Tamir Brosh ◽  
Haim Kalman ◽  
Avi Levy
Keyword(s):  
Pneumatic Conveying ◽  
Dem Simulation ◽  
Particle Attrition

An Experimental Study of Horizontal Self-Excited Pneumatic Conveying

2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Fei Yan ◽  
Akira Rinoshika
Keyword(s):  
Pressure Drop ◽  
Power Consumption ◽  
Pneumatic Conveying ◽  
Velocity Range ◽  
Air Velocity ◽  
Additional Pressure ◽  
Polyethylene Particles ◽  
Conveying System ◽  
Frequency Features ◽  
Minimum Velocity

A new pneumatic conveying system that applies soft fins mounted vertically on a center plane of pipe in the inlet of the gas-particle mixture is developed to reduce power consumption and conveying velocity. The effect of different fin’s lengths on a horizontal pneumatic conveying is experimentally studied in terms of the pressure drop, conveying velocity, power consumption, particle flow pattern, and additional pressure drop. The test pipeline consisted of a horizontal smooth acrylic tube with an inside diameter of 80 mm and a length of about 5 m. Two kinds of polyethylene particles with diameters of 2.3 mm and 3.3 mm are used as conveying materials. The superficial air velocity is varied from 10 to 17 m/s, and the solid mass flow rate is from 0.20 to 0.45 kg/s. Compared with conventional pneumatic conveying, the pressure drop, minimum and critical velocities, power consumption, and additional pressure drop can be reduced by using soft fins in a lower air velocity range, and the efficiency of fins becomes more evident when increasing the length of the fins or touching particles stream by the long fins. The maximum reduction rates of the minimum velocity and power consumption by using soft fins are about 20% and 31.5%, respectively. The particle concentrations of using fins are lower than those of non-fin near the bottom of the pipe and are higher than those of non-fin in the upper part of the pipe in the acceleration region. Based on analyzing the frequency features of the fin’s oscillation, the Strouhal number of more efficient fins is about St ≈ 0.75 in the air velocity range of lower than 13 m/s.

scholarly journals Measurement and analysis of parameters of the precise grinding system

2019 ◽  
Vol 254 ◽  
pp. 01012
Author(s):  
Krzysztof Tyszczuk ◽  
Kazimierz Peszyński ◽  
Adam Mroziński ◽  
Grzegorz Śmigielski
Keyword(s):  
Laboratory Tests ◽  
Pneumatic Conveying ◽  
Air Velocity ◽  
Measurement And Control System ◽  
Diet Supplements ◽  
Measurement And Analysis ◽  
And Control ◽  
Measurement And Control ◽  
Grinding System

The technological process of materials grinding, especially biological material with high oil content, is quite complex. There are several parameters that impact the performance and quality of the process (e.g. temperature, rotational speed). One of them is the air velocity at pneumatic conveying of grinding particles. The phenomena of pneumatic transport of seeds and its impact on product’s quality and grinding capacity is not methodologically recognized so far. The paper presents the construction details of measurement and control system and results of the research obtained during the laboratory tests. The results of the tests and their analysis will be used for design of a commercial precise grinder, which allowed to reach the optimum product’s capacity and quality, constituting the basis for biological diet supplements.

Flow Characteristics on Fluidized Powder Conveying in a Horizontal Rectangular Channel

2015 ◽  
Author(s):  
Koichiro Ogata ◽  
Sumito Yamashita ◽  
Tomoya Hirose
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Rectangular Channel ◽  
Flow Characteristics ◽  
Glass Beads ◽  
Horizontal Channel ◽  
Solid Loading ◽  
Loading Ratio ◽  
Minimum Fluidizing Velocity

This study experimentally examined the dense phase pneumatic conveying in a horizontal rectangular channel using the fluidizing air. The powder used is PVC belong to Geldart A particle, where the mean diameter is 151μm, the particle density is 1382kg/m3 and the minimum fluidizing velocity is 9.0mm/s. As the experimental conditions, the fluidizing velocity at the bottom of a vessel and the horizontal channel has been changed. Also, the mass of transported powder, the supply air pressure and the height of powder bed inside a vessel were measured. In the case of PVC, we confirmed the flow characteristics of the powder conveying and air pressure. Further, we found that the fluidizing air to the bottom of a vessel was required to the powder conveying of this system, and that the fluidizing velocity at the horizontal channel needs to be larger than the minimum fluidizing velocity. These results were also obtained on the previous study when two kinds of glass bead was used. The mass flow rate and solid loading ratio were estimated by the measured data of the mass of transported powder. In addition, these results were compared with the conveying characteristic of two kinds of glass beads belongs to Geldart A and B particle. As a result, the mass flow rate and solid loading ratio of PVC were smaller than that of two kinds of glass beads.

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