Drum Rotation Speed Research Articles

Experimental Investigation of Magnetic Drum Separation Techniques for Dodder (Cuscuta L.) Seed Removal from Alfalfa Seed Mixtures

Thousands of species of parasitic weeds, such as dodder, pose significant threats to agricultural crops due to their ability to spread rapidly through seeds. When cultivated lands become infested with dodder, the quality of production declines, leading to substantial damage. The most effective way to limit the infestation of agricultural lands by parasitic weeds, particularly dodder, is to control the quality of seeds intended for sowing. To obtain seed material free of dodder seeds, special separation machines equipped with magnetic drums are used. These machines operate on the principle of magnetic fields acting on ferromagnetic particles, which helps differentiate the physical states of the seeds intended for separation. This paper presents experimental research on magnetic drum separation techniques for removing dodder seeds from alfalfa seed mixtures. The study examines variables such as magnetic drum speed, feed rate, amounts of iron powder, water, solution (water and glycerin), and the initial content of dodder seeds. The experimental results indicated that using a water–glycerin solution at optimal concentrations for moistening the seeds enhances the separation efficiency of dodder seeds from alfalfa seed mixtures, compared to using only water. Additionally, the numerical content of dodder seeds in the A and C sorts, which primarily contain the seeds of the main crop, decreases with each pass through the machine, resulting in higher quality seed material. The research found that using appropriate parameters—drum rotation speed (20 rpm), iron powder quantity (19 g/min), and seed feed rate (25.39 g/s)—achieved a “free” classification for dodder in alfalfa seeds. These findings are valuable for evaluating the performance of separation equipment with magnetic drums to obtain high-quality seed material. They are also beneficial for designers, machine-building units, and economic agents specializing in this field.

The Study of Water Content on the Coal Loading Performance of Thin Coal Seam Shearer Drum by Discrete Element Method (DEM)

ABSTRACTAs the main component of thin coal seam shearers, the drum bears the functions of loading and cutting, and its performance has become an important factor restricting mining efficiency and production safety. In response to the problem of low efficiency in installing thin coal seam shearers, this paper uses the Discrete Element Method (DEM) to study the effects of loading methods, helical angle of drum, drum rotation speed, and particle water content on coal loading rate. Research has found that the coal loading performance of the ejection loading method is much higher than that of the pushing loading method. As the helical angle increases, the average loading rate increases. As the rotation speed increases, the loading rate of wet coal particles gradually decreases. During production and thin coal seam mining, special attentions should be paid to the control of helical angle of drum and drum rotation speed. This study has guiding importance for improving the efficiency of thin coal seam mining.

Optimisation of Electrospinning Parameters for High-Strength Oriented Pan Nanofibre Mats

Abstract This study explores the optimisation of electrospinning parameters to enhance the strength and orientation of polyacrylonitrile (PAN) nanofibre mats, which are pivotal in filtration applications and other areas requiring high-strength, uniformly distributed nanofibres. The focus is on the electrospinning process, particularly on a rotating drum collector, which is instrumental in determining the morphology of nanofibres. Key process variables, including the distance between the collector and the syringe, feed rate, applied voltage, and polymer concentration, have been meticulously examined to understand their influence on the physical properties of PAN nanofibres. Our findings indicate that parameters such as voltage, collector-to-syringe distance, and drum rotation speed (RPM) significantly impact the mechanical performance of the nanofibre mats. The optimised electrospinning conditions produced PAN nanofibre mats with tensile strengths ranging from 1.61 MPa to 21.78 MPa, demonstrating a notable improvement in strength due to controlled fluid dynamics and expulsion of polymer solution during the process.

Optimizing rotary kiln operations for molybdenite concentrate oxidation roasting to produce molybdic trioxide

The effects of the rotational speed (0–10 rpm) and temperature (550–650 °C) of rotary kiln drums on the oxidation roasting of molybdenite (MoS2) concentrate was investigated in this study. Computational predictions indicated that production of MoO2 was more favorable than that of MoO3 up to a certain stage of the oxidation roasting process, after which MoO3 is produced through the consumption of MoO2. Thus, understanding the MoS2–MoO2–MoO3 relationship and its equilibrium is important. A drum rotational speed > 5 rpm significantly increased the S reduction rate and considerably decreased the S content at 60 min to < approx. 5 %. Additionally, the S content at 60 min decreased with decreasing the temperature from 650 to 550 °C due to the MoS2 concentrate exothermic reaction during oxidation roasting. The MoS2 to MoxOy (≈ MoO2+MoO3) conversion rate (%) was generally proportional to the rotational speed and reaction duration. X-ray diffraction analysis indicated that 5–10 rpm and 550–600 °C yielded a higher experimental conversion rate (97–98 %). Furthermore, the MoO2 and MoO3 conversions were separately quantified. Agglomeration was more pronounced without drum rotation and at higher temperatures. Analysis of the reaction kinetics using the unreacted-core model indicated that diffusion through the gas film layer is supported by the 20.9 kJ/mol activation energy obtained from the Arrhenius plot. Consequently, an appropriate drum rotational speed at a relatively low temperature is a prerequisite for producing MoO3 through the oxidation roasting of MoS2 concentrates in a rotary kiln.

Preparation and Property Analysis of Antibacterial Fiber Membranes Based on Hyperbranched Polymer Quaternary Ammonium Salts.

Due to their excellent properties, antimicrobial fiber membranes are widely applied in bioprotective materials. This work addresses the preparation of thermoplastic polyurethane (TPU)-based fiber membranes with active antimicrobial properties. 2-hydroxypropyl trimethyl ammonium chloride-terminated hyperbranched polymer (HBP-HTC) was synthesized and used as an antimicrobial agent. The fiber membranes were obtained by electrospinning a mixed solution of HBP-HTC and TPU. Different electrospinning conditions were investigated, such as the spinning voltage and drum rotation speed. The fiber membrane prepared under a 22 kV anode voltage and 100 rpm rotation speed had an average fiber diameter of 1.66 μm with a concentrated diameter distribution. Antibacterial tests showed that when the fiber membrane was loaded with 1500 mg/kg of HBP-HTC, the antibacterial rates of E. coli as well as S. aureus both reached 99.99%, exhibiting excellent proactive antimicrobial performance. Moreover, the protective performance of the fiber membrane was outstanding, with a filtration efficiency of 99.9%, a hydrostatic pressure resistance greater than 16,758 Pa, and a moisture permeability of 2711.0 g⋅(m2⋅d)-1.

Morphology engineering of nanofibrous poly(acrylonitrile)-based strong anion exchange membranes for enhanced protein adsorption and recovery

The (bio)pharmaceutical and food industries are transitioning towards circular economy to minimise waste and foster sustainability in the supply chain of biomolecule-based drugs and supplements. Membrane chromatography is expected to play a crucial role in this transition, with the potential to maximize recovery and reduce operating costs. The development of chromatographical membranes is however impeded by the lack of understanding on the membrane structure – chemistry – performance relationship. Here a one-pot synthesis of anion exchange membranes with engineered nanofibrous morphology was studied by electrospinning the blend of polyacrylonitrile (PAN) and tailored quaternized poly(acrylonitrile)-co-poly(2-(dimethylamino)ethyl acrylate) copolymer containing 15 mol% of functional groups, namely PAN-pAQ membranes. Comprehensive evaluations were conducted on the influence of the electrospinning parameters on the nanofibre morphology, surface properties and binding capacity of model protein bovine serum albumin (BSA). The fibre alignment was shown to play a significant role, i.e., membrane with anisotropic fibres obtained by increasing the drum rotational speed to 2000 rpm allowed a high BSA binding capacity of 166 mg∙g−1, i.e., 45–66 % higher than other membranes with randomly-oriented nanofibres. This study is expected to contribute towards the design of future membranes for effective purification and recovery of biomolecules from natural and waste streams, promoting circular bio-economy.

Exploring transverse particle motion in rotary drums: DEM analysis of the influence of cross-shaped internals on material transport

This study investigates the impact of lifters and cross-shaped internals on the transversal movement of wooden spheres within rotary drums. Utilizing Discrete Element Method (DEM) simulations, the research evaluates the influence of these internal configurations on evolving bulk porosity, particle trajectories and residence time of particles in the central area of the drum. The study analyzes three distinct internal geometries and the influences of parameters such as drum rotational speed, drum fill level, and particle water content. Analysis of the simulation results shows that the mean bulk porosity increases by 4% for a single internal cross and by 7% for four internal crosses compared to a configuration without internals. Additionally, it is observed that the residence time for particles in the center of the drum increases by an average of 2.5 times for a single internal cross and 5.5 times for four internal crosses compared to a configuration without internals.

Optimization and Prediction of Operational Parameters for Enhanced Efficiency of a Chickpea Peeling Machine

Chickpeas hold significant nutritional and cultural importance, being a rich source of protein, fiber, and essential vitamins and minerals. They are a staple ingredient in various cuisines worldwide. Peeling chickpeas is considered a crucial pre-consumption operation due to the undesirability of peels for some uses. This study aimed to design, test, and evaluate a small chickpea seed peeling machine. The peeling prototype was designed in accordance with the chickpeas’ measured properties; the seeds’ moisture content was determined to be 6.96% (d.b.). The prototype was examined under four different levels of drum revolving speeds (100, 200, 300, and 400 rpm), and three different numbers of brush peeling rows. The prototype was tested with rotors of four, eight, and twelve rows of brushes. The evaluation of the chickpea peeling machine encompassed several parameters, including the machine’s throughput (kg/h), energy consumption (kW), broken seeds percentage (%), unpeeled seeds percentage (%), and peeling efficiency (%). The obtained results revealed that the peeling machine throughput (kg/h) exhibited an upward trend with increases in the rotation speed of the peeling drum. Meanwhile, the throughput decreased as the number of peeling brushes installed on the roller increased. The highest recorded productivity of 71.29 kg/h was achieved under the operational condition of 400 rpm and four peeling brush rows. At the same time, the peeling efficiency increased with the increase in both of peeling drum rotational speed and number of peeling brush rows. The highest peeling efficiency (97.2%) was recorded at the rotational speed of 400 rpm and twelve peeling brush rows. On the other hand, the lowest peeling efficiency (92.85%) was recorded at the lowest drum rotational speed (100 rpm) and number of peeling brush rows (4 rows). In the optimal operational condition, the machines achieved a throughput of 71.29 kg/h, resulting in a peeling cost of 0.001 USD per kilogram. This small-scale chickpea peeling machine is a suitable selection for small and medium producers.

Electrospun thermoplastic polyurethane membrane decorated with carbon nanotubes: A platform of flexible strain sensors for human motion monitoring

A piezoresistive flexible strain sensor was developed using thermoplastic polyurethane elastomers (TPU) as the matrix and carbon nanotubes (CNTs) as conductive fillers. Sensitivity, strain range, and tensile cycling stability were concurrently considered during its design. Electrospun TPU fiber membranes were prepared via electrospinning in this experiment, with controllable fiber diameter achieved by adjusting the rotational speed of the electrospinning receiving drum. CNTs were incorporated into a flexible polymer substrate through suction filtration to create the strain sensor. The support structure of the electrospun film served as a carrier for uniformly adhering conductive particles. Well-dispersed conductive CNTs could more easily achieve uniform loading through the pore size of the electrospun fiber film, thereby forming a conductive layer. This study initially determined the influence of TPU content in the spinning solution on the morphology of the electrospun membrane. Subsequently, the effects of CNT content and electrospinning receiving drum rotational speed on the microstructure of TPU electrospun membranes were investigated, along with their impact on the microstructure, mechanical properties, and sensing performance of CNTs/TPU (CT) flexible strain sensors. The results indicate that the electrospun fiber membrane prepared under the conditions of TPU mass fraction of 20 wt% and rotational speed of 100 r/min has a larger average fiber diameter and a more stable scaffold structure. The CNTs/TPU (CT) sensor, prepared by filtering 10 mL of CNTs with a concentration of 2 mg/mL, exhibited the best mechanical properties, with a tensile strength and elongation at break of 6.22 MPa and 575 %, respectively. Additionally, it demonstrated high sensitivity (GF = 420.17 at 200 % strain) and excellent durability stability (300 cycle tests), enabling quick and accurate responses to movements of various parts of the human body, thereby meeting the basic usage requirements of flexible strain sensors.

The impact of changing drum rotation direction on fabric motion and drying performance in clothes dryers

Fabric motion in tumble dryers, particularly the motion observed from the cross-section of the rotating drum, contributes significantly to the heat and mass transfer between textiles and the surrounding hot airflow. However, the wider picture for this process is not yet clear and requires further study. In this article, fabric motion with different drum rotation direction settings was analyzed experimentally to determine the effect of drum rotation direction on drying performance. A high-speed video camera was used to record the fabric motion during the entire drying process. The recorded movies were then processed, and the velocity and occupancy distributions of the tracer fabric and several motion indexes were analyzed by using OpenCV and Matlab. The results indicated that changes in the drum rotation mode cause significant variations in the dynamics of fabric motion in domestic tumble dryers across different drying conditions with variations in fabric size, drum rotation speed and load size. Constantly changing drum rotation direction plays an important role in enlarging the motion area and reducing the passive motion area, lifting the textiles up to a higher place and agitating the mixture inside the rotating drum. This means that the fabrics can be effectively scattered instead of tangling together, and because this drying condition provides more opportunities for them to be exposed to the surrounding hot airflow, it enhances convective heat and mass transfer within the drying chamber and reduces the formation of wrinkles on fabrics. This study could lead to new guidance for obtaining effective fabric motion patterns that lead to an optimal drying performance.

Research on dynamic characteristics of cutter breaking frozen soil and optimal drum rotation speed of the new shaft tunneling machine

To improve the efficiency of frozen soil excavation, the new shaft tunneling machine was developed. The new shaft tunneling machine exerts pressure on the frozen soil through the cutter under the joint action of its own gravity, the drum rotational force and the inertia force, and the frozen soil is damaged. By unique way of breaking frozen soil to improve the efficiency of frozen soil excavation, the drum rotation speed is one of the factors affecting the performance of frozen soil excavation. This article applies SolidWorks software to establish the model of cutter breaking frozen soil, takes advantage of Hyper Mesh finite element software coupled with LS-DYNA solver to acquire the regular pattern of change in the force change, frozen soil stress–strain and specific energy of cutter crushing frozen soil, etc., which analyzes the destruction of frozen soil when the drum of the new shaft tunneling machine is rotating at the speed of 25–40 rpm. Combine with field test to investigate the mechanism of cutter breaking frozen soil under the optimal drum rotation speed. The investigation results demonstrate that: when frozen soil's self-bearing capacity is lower than the force of cutter, it breaks up and detaches from the soil body, and frozen soil undergoes tensile, compressive and shear damages. For this research, it is instructive for practical engineering.

Analysis of Temperature Distribution on the Coffee Roaster Drum for a Capacity of 2 kg Using Computational Fluid Dynamics (CFD)

Coffee, one of Indonesia's largest commodities, is often processed using traditional methods and tools that rely heavily on manual labor and can be labor-intensive. To make the coffee roasting process more efficient and reduce the need for human effort, a coffee roasting machine can be used. This study aimed to analyze coffee roasting drums using computational fluid dynamics (CFD) to determine the optimal drum thickness and rotation speed in a coffee roasting machine. The study considered three different thicknesses (1mm, 2mm, and 3mm) and three different rotation speeds (60rpm, 65rpm, and 70rpm). The coffee roasting drum was modeled using CFD. The study's results showed that a drum thickness of 2mm and a rotation speed of 70rpm achieved the best heat distribution during roasting, reaching the desired temperature in 900 seconds. This information could be used to design a more efficient coffee roasting machine or improve the performance of existing machines.

Enhancing Seed Germination and Seedlings Growth of Khao Dawk Mali 105 Rice Cultivar via Seed Coating and Infrared Drying Apparatus

Seed coating techniques had emerged as a promising approach for precise planting and safeguarding crops against environmental stresses. Simultaneously, infrared drying, renowned for its cost-effectiveness and efficiency, held promises for enhancing the quality of drying processes. This investigation delved into the procedures applied to Khao Dawk Mali 105 rice seeds during the coating and drying process using a prototype of the hexagonal drum. The results found that the drying temperature (factor B) and duration of drying time (factor C) had substantial primary effects (p ≤ 0.05), while the drum rotational speed (factor A) did not exert a noteworthy influence. Additionally, meaningful interactions were observed among the factors AB, AC, BC, and ABC. Impressively, it resulted in germination rates of 80.56 and 80.25 %, coupled with germination indices of 84.88 and 85.47 %, when utilizing a drum speed of 20 rpm, a drying temperature of 45 °C, and a drying time of 8 min (R-204508), and a drum speed of 10 rpm, a drying temperature of 45 °C, and a drying time of 8 min (R-104508), respectively. Additionally, the mean germination time amounted to 9.64 days, and the length of the rice seedling stem reached 13.66 cm when employing a drum speed of 20 rpm, a drying temperature of 50 °C, and a drying time of 8 min (R-205008). These discoveries emphasized the potential of the prototype's seed coating and infrared drying technology integration to improve rice germination and subsequent growth. This enhancement could ultimately result in higher yields and increased productivity, especially in small-scale agricultural settings. HIGHLIGHTS These discoveries emphasized the potential of the prototype's seed coating and infrared drying technology integration to improve rice germination and subsequent growth. This enhancement could ultimately result in higher yields and increased productivity, especially in small-scale agricultural settings. Ensuring precise control over drying temperature and duration is of paramount importance in establishing optimal and consistent conditions for the germination and subsequent growth of rice seeds, thereby augmenting plant vigor and overall yield The investigation determined optimal coating and drying conditions, encompassing a drum speed of 20 rpm, a drying temperature of 45 °C, and a drying duration of 8 min (treatment R-204508), along with a drum speed of 20 rpm, a drying temperature of 45 °C, and a drying time of 8 min (treatment R-104508). These conditions resulted in the highest mean germination rates and germination indices. GRAPHICAL ABSTRACT

The Effect of Drum Dryer Temperature and Rotational Speed on the Characteristics of Finger Millet (Eleusine coracana) Based Weaning Food Enriched with Composite Flour

Abstract Finger millet or red millet is a source of carbohydrates, protein, and phytonutrients that have not been widely used. This has the potential to be used as an ingredient in making bread and porridge. However, the protein content of millet is insufficient for infant feeding and deficient in essential amino acids like lysine, so other ingredients are needed. This study contrasted composite flour dried at various temperatures and rotational speeds with millet-based supplementary feeding. Finger millet flour, red bean, skimmed milk powder, sugar, and salt were used to produce the weaning meal in that sequence. The dough-to-water ratio is 1 : 4. Organoleptic, physical, and chemical interactions were all considered. The experiment used a randomised block design with three replications and a 3 × 3 factorial pattern. The study discovered that drum dryer temperature impacted chemical, physical, and sensory responses (p &lt;0.05). Temperature had a more significant influence on moisture content than rotational speed. Temperature above 120 °C results in lower moisture content at rotation higher than 1.0 min−1 and meets the criteria for instant porridge (lower than 4%). Lower moisture content at higher temperatures leads to increased protein concentration, but carbohydrates and fats remain relatively constant. The samples more preferred by the panellists were samples processed at higher temperature with rotation above 1.0 min−1. So, this value is recommended, apart from fulfilling the standard criteria, processing with higher rotational speed can increase the output capacity of the process.

Experimental and numerical evaluation for drum dynamic reliability under extremely complex working conditions

Coal mining machine drums are prone to damage and malfunction under extremely complex working conditions, which seriously affects the efficiency and safety of coal production. In this paper, based on the theory of coal rock cutting and virtual simulation technology, finite element models of drum cutting coal rock were established and then verified by physical experiments. Through simulation analysis, the dynamic reliability of the drum was studied from three aspects: load, stress and wear, and a mathematical model of drum load was established with respect to the traction speed and drum rotation speed; based on the orthogonal test, the optimal working parameters to improve the wear resistance of the drum were derived. The results of the study found that when the traction speed increases, the load on the drum increases, and when the drum rotation speed increases, the load on the drum decreases; when the traction speed is increased from 2 to 6 m/min, the stress on the pick body under different rotation speeds increases to different degrees, with an average increase rate of 27.394%; when the drum rotation speed is 90 r/min, the traction speed is 3 m/min, and the coal loading mode is projectile loading, the wear depth of the picks and spiral blades is relatively small. The research method and results of this paper can provide a reference for the selection of the drum working parameters.

Determination of the optimal modes of operation of the clover grater and scarifier KS-0.3 P during scarification

The article provides information about the features of the device, the quality of work of the prototype of a new 25...30 % more productive clover grater and scarifier KS-0.3 P in comparison with the analogue KS-0.2 P. KS-0.3P includes a drum-type wiping and scarifying device, a pneumatic separation device, a two-stage exhaust air purification system containing a cyclone and a fabric filter. The increase in the productivity of the new machine is achieved by increasing the diameter of the drum with a solid wiping surface to 0.45 m and the length of the oval deck with scarifying plates to 0.7 m. The solid grating surface of the drum is welded from steel rods of hexagonal profile No. 12 mounted on an edge. The deck covering the drum from below by 180° is made of round bars with a diameter of 10 mm and nine steel plates with a thickness of 2 mm and a width of 11 mm, evenly distributed along the length of the deck. When studying the technological process of clover grater and scarifier the method of mathematic planning of the experiment was used. The quality of scarification done was evaluated using the GOST 12038-84, GOST 12036-85 methodologies and additionally introduced indicator of variation of the number of germinated seeds. The material supply was regulated by the degree of opening of the flap in the loading hopper in the range from 0.2 to 0.4 t/h. The rotation frequency of the drum was changed by a frequency converter from 550 to 650 min-1. Eastern galega seeds met GOST 52325-2005 requirements. The experiments were carried out in three-fold repetition. As a result of an experimental study of the KS-0.3P cloverworm-scarifier during the scarification of the seeds of the Eastern galega, the ranges of the optimal drum rotation speed of 550... 650 min-1 and the material supply of 0.3... 0.4 t / h were determined, when the specified agrotechnical indicators were provided: the degree of scarification not less than 95.0 % and crushing not more than 1.5 %.

Experimental and Computational Fluid Dynamics Investigation on Tanning Process in a Rotating Drum

Mass transfer of chemicals greatly affects leather production efficiency and product quality. Leather shows different motions in a rotating drum during processing, which is strongly associated with chemicals’ mass transfer. However, how leather motions affect mass transfer remains unclear, which disfavors highly efficient leather manufacturing process. Here, different leather motion states were obtained by adjusting the drum rotation speed. Experimental results showed that the duration of leather rolling motion greatly increased by 41% when the rotation speed increased from 5 r/min to 20 r/min, and the uptake of the tanning agent was consequently improved, which indicated that the rolling motion is beneficial to mass transfer. Computational fluid dynamics simulation results showed that the mass transfer rate under rolling motion was higher than those under slipping, elevating and hanging motions, because the flow velocity and concentration gradient near the leather surface were higher under rolling motion. Accordingly, increasing the rolling motion enhanced the mass transfer in leather processing. This work identifies the leather motion beneficial for mass transfer and provides guidance on operating condition optimization and drum design for high-efficiency leather production.

Drying Schinus terebinthifolius leaves in a rotating drum dryer – Evaluation of the product quality and energy consumption by RSM models

The performance of a specially designed rotating drum for processing medicinal leaves was evaluated for air drying Schinus terebinthifolius leaves. The study is aimed at investigating the influence of air temperature, air velocity, leaf mass load, and drum rotation speed on leaf drying. Response Surface Methodology (RSM) was employed to optimize the drying conditions. Second-order polynomial equations were used to assess the effects of drying conditions on drying time, color degradation, and energy consumption. Based on the analysis, the optimum drying conditions were determined to be an air temperature of 52.5 °C, air velocity of 0.3 m/s, and a mass load of 200 g. The predicted values of drying time, specific power input and the chromatic parameter a*/b* at this optimal condition were 499 min, 14.4 kWh/kg and − 0.063, respectively. Furthermore, a comparison between ethanolic extracts obtained from fresh leaves and those from dried leaves revealed a significant decrease in total phenolic compounds (TPC) and antioxidant activity (AA) in the extracts from the dried leaves. Among the tested conditions, the best result for both TPC and AA was observed in the extracts of leaves air dried under 50 °C and 0.60 m/s, in which the TPC and AA dropped respectively from 75 mg GAE/mg dry matter and 90 % to approximately 22 mg GAE/mg dry matter and 88 %. The air temperature was identified as the most influential factor affecting the quality attributes of dried leaves and their extracts. The rotating drum proved to be an effective alternative for drying herbs and medicinal leaves.

READY-TO-EAT CHICKPEA PURÉE POWDER BY DRUM DRYING; PHYSICOCHEMICAL AND RHEOLOGICAL PROPERTIES OF POWDER PRODUCT

This study aims to convert raw chickpea (Cicer arietinum L.) into dried chickpea puree powder form using a drum dryer having a high rehydration ratio and for ready-to-use consumption form maintaining its healthy properties. The effects of the drying conditions on the physical, chemical, and rheological properties of chickpea puree powders were investigated. Before drying, raw chickpeas were soaked in water at 25°C for 12 hours and boiled at 100°C for 55 minutes. In the drying process, saturated steam pressures (2, 3, and 4 bar) and drum rotation speeds (2.0, 3.0, 4.0, and 5.0 rpm) were chosen as process variables. The most appropriate process conditions were determined as 3 bar of steam pressure and 2 rpm of drum rotation speed targeting the maximum protein content (30.35±0.18%), maximum rehydration ratio (515±0.01%), and as low as possible browning index (BI)(59.28±4.90) values. It was determined that chickpea puree had the appropriate rheological characteristics when the shear stress and shear rate values for chickpea puree powders with various dry matter contents (%25, %26, %27.5, %30) produced under suitable process parameters were examined.

Numerical investigation of the particle flow behaviors in a fluidized-bed drum by CFD-DEM

The fluidized-bed drum technology involving the combination of a fluidized bed and a rotating drum is used for the granulation and coating of particles, which has been successfully applied in industry. Nevertheless, there should be few published fundamental studies for exploring the particle flow behaviors in a fluidized-bed drum, particularly in the particle level. Consequently, the particle-scale DEM (Discrete Element Method) was coupled with CFD (Computational Fluid Dynamics) in this work to simulate the particle-fluid flow system in a fluidized-bed drum. The experiments in a small horizontal fluidized-bed drum were also carried out to validate the accuracy of our CFD-DEM model. Subsequently, the particle flows in a large inclined fluidized-bed drum were simulated by CFD-DEM, and the relatively comprehensive investigation for the influences of operational conditions (including the gas inlet velocity, drum rotation speed, drum inclination angle and fluidized-bed inclination angle) on the particle flow behaviors (e.g., the particle holdup, particle velocity and particle residence time) was carried out. According to the simulation results, the particle flow behaviors would be significantly affected by these operational conditions. However, increasing the gas inlet velocity could weaken the effects of drum rotation speed, drum inclination angle and fluidized-bed inclination angle.