Rotary Disk Research Articles

Development and characterization of a novel rotary magnetorheological fluid damper with variable damping and stiffness

A novel compact rotary magneto-rheological (MR) damper with variable damping and stiffness has been proposed and analyzed. Its variable damping is generated by tuning yield stress of MR fluid in both pre-yield and post-yield regimes. The controllable storage modulus in pre-yield region of MR fluid is used to achieve magnetic field dependent stiffness. To ensure the MR rotary damper output variable stiffness in large angle, a unique structure that contains two driven disks and an active rotary disk is proposed. The effects of current, angle and frequency on the torque–angle loops and torque-frequency loops have been investigated experimentally. Adaptive network based fuzzy inference system with learning ability is adapted to capture the non-linear behaviors of variable damping and stiffness. By comparing with the MR dampers with one driven disk and that with no driven disk, it can be found that the proposed MR rotary damper with two driven disks can provide variable stiffness in larger angle. The results made the concept of proposed damper with variable damping and stiffness become feasible.

A novel posture control device to induce high-rate complex loads for spine biomechanical studies

Modern environmental scenarios such as autonomous vehicles, aircrafts, and military vehicles position the human body in a nonstandard posture and induce multiplanar loads; however, current spine alignment methods and loading are based on sagittal and planar loads. The objective of this study is to develop a posture control device and demonstrate its ability to induce multiplanar loads to the human cadaver spinal columns. The inferior end of the device was designed to allow a full six degree-of-freedom control for positioning the specimen via a coupled x-y cross table, vertical lift platform, and triaxial rotation mechanism. The superior end of the device was designed such that the cranial fixation of the specimen could be attached to the piston of the electrohydraulic testing apparatus directly or via a rotary disc through a slider-crank mechanism. The former attachment induces complex forces and moments, while the latter induces controlled moments with minimal forces. The usability of the posture control device was demonstrated by conducting experiments with a thoracolumbar spinal column for combined forces and moments, and with a head-neck column for complex moments, and in both cases, the uniaxial travel of the piston was at a dynamic rate. The posture control device can be used to study the biomechanics of the spine under complex loads and with different postures and develop injury criteria for different field environments.

Online size distribution measurement of dense iron green pellets using an efficient and multiscale nested U-net method

Accurately measuring the pellet size distribution during the pelletizing process is critical, because the pellet size distribution is a key quality indicator and affects the efficiency of the blast furnace. In this study, a method based on a convolutional neural network is proposed to measure the pellet size distribution in the stable area of a rotary disc. The proposed network only uses simple convolution layers in sequence to realize multiscale performance; furthermore, it uses a bottleneck layer and a concatenate path to improve the computing efficiency and alleviate the vanishing gradient problem, respectively. Various experimental results demonstrate that the proposed network outperforms other comparison methods in segmenting overlapped pellets, especially pellets of different sizes. The pellet size distribution obtained by the proposed method agreed well with the manual sieving results. Moreover, the computing time of the proposed method can meet the requirements of online size distribution measurement.

Removal of Toxic Phenolic Compounds from Wastewater Using Zeolite (4A) Prepared from Local Clays Taken from the Slopes of the Tigris River

The massive scale of industrial development has resulted in environmental pollution in general and water contamination in particular. It is important at the present time to treat water for the purpose of eliminating or reducing pollutants, especially toxic pollutants, such as phenol compounds. In this study, zeolite (4A) was prepared firstly from the available and cheap materials using an inclined rotary disk. Then, physical, mechanical, and chemical properties were also studied. Experiments were conducted to determine these properties using local clay and the following results were obtained: Zeolite (4A) 70% and clay 30%, the time of calcination 3 h at a temperature of 850��C, breakage resistance of 17 Ib pounds, surface area 530-590 m2/g, grinding value 14% and moisture absorption ratio 30%. The prepared zeolite (4A) was used in the process of removing phenolic compounds (chlorophenol, nitrophenol) by the adsorption method. Different amounts of prepared zeolite (5g/l and 10g/L) will be used in the treatment process and different concentrations (2mg/L, 5 mg/L and 10 mg/L) of the pollutants Nitrophenol and Chlorophenol were used in the contaminated water tested. The removal process was carried out with a mixing speed of 200 rpm and pH (7.5-8.5). From the results of this study, we note that the highest percentage of Nitrophenol removal is (84.8%) when using an amount of zeolite (5g) and highest percentage of Nitrophenol removal is (95.5%) when using an amount of zeolite (10g) while that the highest percentage of Chlorophenol removal is (78.3%) when using an amount of zeolite (5g) and highest percentage of Chlorophenol removal is (0.894) when using an amount of zeolite (10g) it could be deduced that the percentage of the removal of nitrophenol was higher than that of chlorophenol because its solubility of chlorophenol in water is higher than the solubility of Nitrophenol.

Continuously Separation of Sodium and Potassium Using an Adsorption Rotating Disc

This paper is dealing with one of the applications of liquid chromatography using rotary disks. The research aims to study the effect of using distilled water (PH = 7) as a carrier phase and its absence on the practical results using NaOH and KOH at different speeds (2500, 3000, 3500 rpm). As well as choosing the best ratio of the diameter of the rotary disk nozzles that achieves the best displacement between the NaOH and KOH slides with paths separated from each other. Then propose a mathematical model that shows how the thickness of the slice sector behaves with changing the rotational speed. After that, calculating the pressure caused by the rotation and evaluating the results up to a speed of 12000 rpm. The practical results proved that the carrier fluid has an apparent effect on the displacement value between NaOH and KOH slides by changing the internal and external diameters of the rotating disk nozzles and the rotational speed from (500-3500 rpm). The effect of each of them was clear on the displacement of the injected slices from the center of the rotating disk and the convergence between the practical and theoretical results.

Design Enhancement and Thermal Analysis of Disc Brake

In automobiles, the function of disc brakes is controlled by jamming the brake pads opposed to a rotary disc that is usually attached to a wheel. A composite material set is preferred to manufacture the brake pads. This braking process produces frictional forces which cause deceleration and eventually stops the rotation of the disc. The indulgence of the generated heat due to friction is important for successful braking. Changes in temperature of the brake cause radial and axial bend; this variation in shape, in turn, distresses the proper alignment of the pads and the disc. The aim of this paper is to design a brake disc and perform the thermal stress analysis by applying five different materials namely Gray cast iron (GCI), reinforced Ti-composite (TMC),Ti-alloy (Ti-6Al-4V), reinforced Al-Cu alloy(AMC 2), and reinforced Al-composite(AMC 1).The modelling and analysis of the disc brake are achieved with the aid of SOLIDWORKS and ANSYS software.

Rotary disk multi-phase freestanding-electret generator with enhanced power and low ripple output

Energy harvesters with higher power and direct-current (DC) output are of great significance for the energy supply of electronic devices. Here, we demonstrate rotary disk multi-phase freestanding-electret generators (MFEGs) with enhanced output power and low ripple output via a novel design. This novel design can enhance the output power by the reduction of generator capacitance and the improvement of the transferable charge density through positively utilizing the edge effect. The factors which both theoretical and experimental results show that the two- and three-phase FEGs have higher maximum output power than that of the conventional single-phase FEG (SFEG) and the two-phase FEG (TFEG) has the highest one. To further improve the output power, we optimize the structural parameters of TFEG and obtain 78.4% higher maximum output power than that of the optimal SFEG in experiment. Moreover, MFEGs connected to rectifier bridges obtain almost DC outputs. And since each phase of MFEGs is independent, the output of each phase can be utilized separately, for example, one as sensing signal and the other as energy output, providing a broad prospect for self-powered sensing. • Rotary disk multi-phase freestanding-electret generator (FEG) is demonstrated with enhanced power and low ripple output. • Output power enhancement is benefited by generator capacitance reducing and positively utilizing the edge effect. • Two-phase FEG has the highest maximum average power, 78.4% higher than the conventional single-phase FEG. • Each phase of MFEG is independent, which can be used separately, one as sensing signal and the other as energy output.

Effect of process parameters on dry centrifugal granulation of molten slag by a rotary disk atomizer

Dry centrifugal granulation (DCG) experiments for blast furnace slag (BFS) were performed by means of a rotary disk atomizer since water quenching method can create a series of problems. The results showed that the DCG method can granulate the BFS, but the results are easily affected by the slag flow rate, disk rotating speed, disk radius, disk material and slag falling height. The granulating parameters with an excessive flow rate, low rotating speed, SiN–SiC disk, stainless steel disk and low slag falling height are detrimental to the granulation process. The most suitable parameters for granulation are a slag flow rate of 5.1 × 10−5 m3/s, a disk rotating speed of 1500–2300 r/min, a slag falling height of 0.8 m and a smooth graphitic disk with the radius of 0.1 m. In the absence of an off-center flow, the overall best granulating effect produces round particles with mean diameter of 3.43 mm without creating slag fiber. The vitreous content of the BFS particles granulated by graphite disks is 92%, which meets the requirements of cement raw materials. The Bond work index of dry granulated BFS is 18.4 kWh/t, and the grindability of dry granulated slag and water-quenched slag is similar.

Mass transfer and Cattaneo-Christov heat flux for a chemically reacting nanofluid in a porous medium between two rotary disks

This paper examines the transport of a chemically reacting nanofluid in a porous medium between two rotary disks with Cattaneo-Christov?s heat flux. The non-linear ordinary differential system formed under Vonn Karman transformation of a non-linear partial differential system is solved via a shooting method with MATLAB bvp4c. The nanofluid thermodynamics profiles with variation in physical properties of thermal relaxation time, thermal radiation, porosity, and chemical reaction are observed. Axial, radial, and tangential velocities are found to be increasing functions of porous medium. A decrease in the fluid temperature is perceived as thermal radiation and thermal relaxation increase since more heat can be transported to neighboring surroundings. The concentration is enhanced with intensified Cattaneo-Christov?s thermal relaxation but it oscillates with reacting chemicals. The rotary disks bound the oscillating nanofluid from downward to up-ward directions and vice versa. The axial velocity represents the change in force due to porosity and radial stretching of the disks.

Dynamic stability analysis of a rotary GPLRC disk surrounded by viscoelastic foundation

The research presented in this paper deals with dynamic stability analysis of the graphene nanoplatelets (GPLs) reinforced composite spinning disk. The presented small-scaled structure is simulated as a disk covered by viscoelastic substrate which is two-parametric. The centrifugal and Coriolis impacts due to the spinning are taken into account. The stresses and strains would be obtained using the first-order-shear-deformable-theory (FSDT). For Poisson ratio, as well as various amounts of mass densities, the mixture rule is employed, while a modified Halpin-Tsai model is inserted for achieving the elasticity module. The structure's boundary conditions (BCs) are obtained employing GPLs reinforced composite (GPLRC) spinning disk's governing equations applying principle of Hamilton which is based on minimum energy and ultimately have been solved employing numerical approach called generalized-differential quadrature-method (GDQM). Spinning disk's dynamic properties with different boundary conditions (BCs) are explained due to the curves drawn by Matlab software. Also, the simply-supported boundary conditions is applied to edges θ=π/2 and θ= 3π/2, while, cantilever, respectively, is analyzed in R=Ri, and R0. The final results reveal that the GPLs' weight fraction, viscoelastic substrate, various GPLs' pattern, and rotational velocity have a dramatic influence on the amplitude, and vibration behavior of a GPLRC rotating cantilevered disk. As an applicable result in related industries, the spinning velocity impact on the frequency is more effective in the higher radius ratio's amounts.

Atomizers in spray dryers: a review

Atomization is the most important step in spray drying that defines the properties of liquid droplets after spraying, resulting in various forms of the dry product - from fine powders to granules. It basically refers to the disintegration of the liquid into droplets in the presence of a drying gas circulating in the medium, increasing its surface area until the droplet becomes unstable and disintegrates. The choice of the atomizer's configuration depends on the nature, viscosity of the supply and desired characteristics of the dried product. Atomizers are classified according to the three basic forms of energy commonly employed for the atomization: pressure energy; centrifugal kinetic energy and gaseous energy. This results in the three most common atomizer models: pressure nozzles, rotary disc atomizers and pneumatic nozzles. The sonic and vibrating atomizers are less common. The difference between the atomization enables one to obtain different droplet sizes and, consequently, a different particle size distribution. The selection of the atomizer can be based on some important considerations, such as availability, flexibility, energy consumption or particle size distribution of the dry product.

Fabrication of copper centered metal organic framework and nitrogen, sulfur dual doped graphene oxide composite as a novel electrocatalyst for oxygen reduction reaction

The main focus of this study is to synthesize a free – platinum electrocatalyst for ORR applications. Since the price of copper is much lower than platinum, the Copper - centered Metal Organic Framework (Cu - MOF) is selected as the electrocatalyst. The electron conductivity of MOFs is low. Accordingly, in order to enhance the ORR kinetics and electrochemistry activity, for the first time, Nitrogen and Sulfur Dual-Doped Reduced Graphene Oxide (NS - RGO) with different concentrations are incorporated into the Cu – MOF structure. In other words, NS-RGO has high electrical conductivity which can operate as an efficient carrier for electron transfer. For evaluating the structural properties and morphology of synthesized electrocatalysts, six main characterization techniques, consist of XRD, FESEM, Raman, EDS, TEM, and FTIR are employed. Also, in order to assess the durability and ORR activity, the electrochemical measurements are performed. The electrochemical tests are implemented using the Rotary Disk Electrode (RDE) device in the alkaline medium. Based on the achieved results, the best ORR activity is related to the 8% NS – RGO - Cu – MOF catalyst. The onset potential and electron transferred number (n) of this catalyst are obtained to be −0.06 V vs Ag/AgCl and 3.53, respectively. In other words, it tends to favor the 4e-pathway for ORR. In this project, the relationship between structure and electrochemistry activity of non-precious metal/carbon composites is investigated. materials Finally, the electrochemistry activity of synthesized electrocatalysts is compared to the previous investigations and commercial 20 wt% Pt/C. These comparisons indicated that mixing different concentrations of NS-RGO with Cu-MOF can improve the electrochemistry activity of MOFs considerably. Actually, the NS – RGO - Cu – MOF composite can be considered as a new cost-effective electrocatalyst that can help to the development of fuel cell technology.

Cocaine degradation using a rotating biological disc reactor: Techno-economic and environmental analysis using experimental data

A bacterial mixed culture that utilizes cocaine as the sole carbon and energy sources was isolated and used in a Rotary Disc Reactor as an alternative method for the final disposal of seized cocaine. This study aimed to compare the performances of cocaine incineration (oven) and biodegradation (Rotary Disc Reactor), considering economic and environmental aspects. There was a 99.4% cocaine removal efficiency when bacterial C1T consortium was grown in a Rotary Disc Reactor for 42 h. The economic analysis allowed determining the high potential of the biotechnological cocaine degradation to be evaluated at higher scales. Indeed, the unit disposition price of the biotechnological degradation pathway was 58% higher than the calculated value for the incineration process considering an initial cocaine concentration of 30 g/L. Moreover, the economic sensitivity analysis demonstrated a price reduction of 20% in the unit disposition price of the biotechnological degradation using a rotary disc reactor. Further, cocaine degradation using a rotary disc reactor system presented a better environmental performance than the incineration process considering atmospheric and toxicological impact categories because of the low release of hazardous materials to the atmosphere.

Prediction on particle size characteristics of high-temperature liquid blast furnace slag in a centrifugal granulation process

The centrifugal granulation technique has the potential for high value-added resource utilization and simultaneous waste heat recovery from blast furnace (BF) slag. Particle size characteristics which provide guide for the determination of operation conditions, are main criterion for assessing the system performance. However, limited by the harsh experimental conditions, no correlation formula of real BF slag particle size has been proposed. In this paper, a three-dimensional model was constructed to describe granulation behavior of liquid slag via rotary disk, with discussion given to the ligament fragmentation detail, characteristic time, particle size distribution and number distribution. Notably, an expression combined with dimensionless parameters was developed to predict the mean diameter of real BF slag granules. The flat disk and arc-edge disk were found to be appropriate for practical application due to their ability to obtain small slag particle size and to suppress slag wool formation.

Metal coatings based on complex compounds of copper (II) with organophosphorus complexones

An important problem of the metal coatings formation processes is the choice of complexing agents for the preparation of process solutions. Nowadays a large number of complex electrolytes for metal deposition have been developed and introduced into production. However, the search for new, more efficient ligands allowing to obtain coatings with specified functional properties is an urgent task and constantly attracts the attention of researchers. To optimize and develop promising technological processes for producing metal coatings, experimental studies of electrode reactions in complex electrolytes are necessary. From this point of view, the study of electrochemical behavior of complex copper (II) ions with hydroxyethylidene diphosphonic acid is of considerable theoretical and practical interest. Oxyethylidene diphosphonic acid forms stable complexonates with copper (II) ions, the compound is non-toxic and available on an industrial scale. To study the kinetics and mechanism of copper deposition from solutions based on copper (II) complex compounds with hydroxyethylidene diphosphonic acid we used modulation spectroscopy of electroreflection, chronopotentiometry, and a rotary disk electrode. The paper shows that with increasing pH of the solution, the overpotential of copper increases due to a change in the composition of the discharging complex ion and adsorption phenomena on the electrode surface. In strongly alkaline solutions, the discharge of complex ions flows from the adsorbed state.

Experimental Assessment of the Impact of Agricultural Machinery on Wood Turtles (Glyptemys insculpta)

The wood turtle (Glyptemys insculpta) is a threatened species that uses agricultural fields, in part, to nest, bask, and feed. This use of anthropogenic habitats has resulted in the injury and death of individuals during crop harvest. Turtles have been exposed to hay harvests for over a century but the increased use of rotary disc mowers may have increased mortality rates to unsustainable levels. Mitigation measures have focused on raising blade height to minimize contact with turtles but these measures are based on the dimensions of the largest turtles and the effects of agricultural machinery on subadults, juveniles, and hatchlings have not been quantified. We sought to quantify how different agricultural machinery affects wood turtles at multiple life stages through experimental trials using 2 mower types. Cantaloupe (Cucumis melo) halves were used as turtle proxies to avoid actual harm to turtles. We found that rotary disc mowers resulted in a significantly greater injury to adult (i.e., female, male, and subadult) and young (i.e., juvenile and hatchling age class) proxies at low grass heights (10–20 cm) compared with sickle cutter bar mowers. Young proxies were found to be essentially unaffected by the sickle mower at all grass heights, but they were highly affected by the rotary disc mower at grass heights from 10 to 18 cm. If blade heights were to be raised to reduce the risk to wood turtles, a minimum blade height of 17 cm would be needed to obtain > 50% of adults remaining undamaged during harvest and a minimum height of 15 cm would be needed for young turtles.

Biofilm reactors for value-added products production: An in-depth review

Biofilms in the environment can both detrimental and beneficial effects. On the other hand, biofilms can be useful for wastewater treatment, bioremediation, and removal of toxic pollutants. Furthermore, biofilms can be used for the productions of value-added products (VAPs) such as biofuels, polysaccharides, antibiotics, organic acids, vitamins, and enzymes. To establish biofilms in the reactors, solid support materials (SSMs) made of inorganic compounds and various agricultural by-products. For these, several types biofilm reactors (BRs) have been utilized such as stirred tank biofilm (bio)reactor (STBR), fluidized-bed biofilm (bio)reactor (FBR), fixed/packed-bed biofilm (bio)reactor (PBR), rotary disc biofilm (bio)reactor (RDR)/rotating biological contactor (RBC), membrane biofilm (bio)reactor (MBR), moving bed biofilm (bio)reactor (MBBR) and trickling filter biofilm (bio)reactor (TBR). The benefits of BRs: increase product yield, provide logarithmic phase growth, reduce lag phase and fermentation time for repeated fermentations, increase biomass population, provide resistance toward toxic compounds, and improve product recovery. This review paper will summarize the literature for biofilm formation and structure, BR types, biofilm support materials, and various VAPs-produced by using BRs. • Biofilm reactors are effective tools for the production of added-value products. • Support materials are used to form biofilm in the biofilm reactors. • Biofilm support materials can be of organic and inorganic structure. • They increase product yield and biomass population and improve product recovery. • Modeling provides information about kinetic-metabolic nature of the fermentations.

Extraction of essential constituents from effluent of hydro-distillation of fennel and investigation of hydrodynamic parameters using a rotary disc column (RDC)

There are different methods for the extraction of essential constituents from medicinal and aromatic plants; however, extraction with the aid of hydro-distillation is a common and feasible technique. In hydro-distillation, essential oils are extracted by water (solvent) and heat (process accelerator). Generally, this approach allows the extraction of essential constituents from generated wastewater. In this study, fennel, with antioxidant and antibacterial characteristics, was used for the extraction of essential oil. The major components found in fennel essential oil include Anisole, Estragole, Fenchone, and Limonene. The mass transfer of the extraction process in the RDC column was investigated with Anisole as the solute. The solvent used in this study was n-hexane (dispersed-phase). The effects of three parameters including dispersed-phase flow rate (3.8, 4.1, and 35 cc/min), nozzle size (1 and 1.5 mm), and rotor speed (75,125, and 175 rpm) on the holdup and mean drop size were assessed. For mass transfer evaluation of anisole, response surface methodology (RSM) was adopted. It was observed that at the optimum point, the amount of efficiency based on Anisole was 52%.

Design and test of 2ZYM-2 potted vegetable seedlings transplanting machine

In order to improve the efficiency and quality of transplanting vegetables in dry land, based on the seedling technology, transplanting effect and analysis of the planting process, a potted vegetable seedlings transplanting machine was designed. It mainly comprised rotary disc type feeding mechanism, five-bar duckbill type planting mechanism (simulated duckbill mechanism, disc cam, connecting rod, crank, fork, cable) and power transmission system. Based on the physical parameters of the seedlings and design requirements, it was determined that the diameter of the duckbill was D=90 mm, the opening and closing angle was 25°, and the taper angle was 17°. A test bench with adjustable parameters was built by analyzing the structure of the planting mechanism and the motion of the working process. The digital speckle technique was used to optimize the parameters, so that the length of the crankshaft Ι was S1=100 mm, the length of the crankshaft ΙΙ was S2= 80 mm, the length of the connecting rod Ι was S3=140 mm, the length of the connecting rod ΙΙ was S4=260 mm, the length of rod to connecting the rack was S6=314 mm, and the height of planting track was H=450 mm. According to the above parameters and the control requirements of the duckbill mechanism, the cam stroke was determined to be S=15 mm. And the initial phase difference between the two cams was 180°. The experiment was carried out with pepper seedlings as transplanting objects. The results showed that when the planting frequency was 50-70 plants/min, the seedling upright rate was 93%-91.1%, the planting depth qualified rate was 96%-92%. The leakage rate was 0-0.26%, the variation coefficient of plant spacing was 0.37%-0.67%, the injury rate was 0%, and the mechanical damage degree of the mining surface was 2.43-3.77 mm/m2. The machine can effectively improve the quality of transplanting, which can meet the production needs and design requirements of the mechanism. Keywords: seedling transplanting, planting mechanism, digital speckle, parameter optimization, test analysis DOI: 10.25165/j.ijabe.20201301.5494 Citation: Jin X, Cheng Q, Zhao B, Ji J T, Li M Y. Design and test of 2ZYM-2 potted vegetable seedlings transplanting machine. Int J Agric & Biol Eng, 2020; 13(1): 101–110.

Floating oil skimmer design using rotary disc method

Over the past few years there have been many oil accidents that have occurred in the sea. Oil accidents can occur due to oil spill, drilling processes at sea or due to pipeline leaks. The oil in the sea will float and if not remove will damage the surrounding ecosystem. Therefore, in this paper implements an oil skimmer system which can be used to remove and separate oil from the water. The oil skimmer system is composed of a rotary disc to take oil on the surface of the water and two propellers to move the oil skimmer. The rotary disc and propeller are driven by DC motor which is connected to the motor driver and Arduino Mega as a controller. The oil skimmer is also equipped with a joystick that is used to adjust the rotation speed of the rotary disc and control the movement of the oil skimmer. Based on the results of testing the oil skimmer has been able to take and separate oil on the surface of the water with separation speed of 620.28 ml/min at a speed of 18 rpm.