Disk Speed Research Articles

Design of Cotton Recovery Device and Operation Parameters Optimization

This research aims to optimize the working parameters of the sawtooth-type recovery device for cotton fallen on the ground to enhance cotton’s recovery effect. Firstly, the cotton-picking mechanism and cotton unloading mechanism of the cotton recovery device were designed. The movement trajectory of the serrated tooth end of the designed device, the cotton non-missing picking condition, and the cotton unloading condition were noted. Secondly, virtual simulation technology developed a model of the interaction process between the picking equipment and the soil. To determine the optimal combination of operating parameters for the recovery device, a three-factor, three-level response surface optimization test was conducted using Box–Behnken’s central combination method with operating machine speed, spacing between serrated discs, and serrated disc speed as the test factors, and the picking and impurity rate as the test indexes. In addition, a response surface regression model was developed to analyze the effects of the selected factors on the recovery unit, and each factor was optimized. When the picking and impurity rates were 79.09% and 35.12%, respectively, the optimal operating speed of the machine was 0.96 m/s, the spacing of the serrated discs was 40 mm, and the speed of the serrated discs was 68 rpm. The relative error between the experimental findings and the theoretical optimized values was less than 5%, and the optimized working parameters were reliable. This study can provide a reference for the device used to recover cotton that has fallen to the ground.

New insight into hydrodynamic and cake erosion mechanism during rotating-disk dynamic microfiltration of concentrated bentonite suspensions at different salinity conditions

The present study investigates the dynamic filtration of concentrated slurry fluids containing colloidal clay particles under different salinity, shear flow, and flux rate conditions. The dynamic filtration study was carried out by the filtration cell equipped with a rotating disk to apply shear stress over the membrane surface. A 3D CFD simulation has been implemented to model the hydrodynamic flows inside the filtration cell to obtain the wall shear stress (WSS) on the membrane surface at different disk rotation speeds. The thickness and surface patterns of fouling were captured utilizing a surface profilometer. First, the cake-filtration model was used to predict the flux rate and fouling thickness under static filtration. Then, the corresponding filtrate flux at stabilized cake thickness under shear flow conditions was calculated. The results showed that increasing the suspension salinity causes the reduction of rheological properties and increases the cake permeability due to the compression of the electrical double layer around clay particles. The results also revealed that increasing the flux rate condenses the cake and reduces erosion. Finally, a model for predicting the rate of fouling removal during dynamic filtration was developed using nonlinear regression. The results showed that a sigmoidal function with appropriate accuracy (R2>0.96) could describe fouling thickness patterns with WSS. Moreover, the mean cake thickness decreased by 80% as the WSS increased from 0 to 2 Pa, where the rotating disk speed increased from 0 to 500 rpm.

Single-Neuron PID UAV Variable Fertilizer Application Control System Based on a Weighted Coefficient Learning Correction

Agricultural unmanned aerial vehicles (UAVs), which are a new type of fertilizer application technology, have been rapidly developed internationally. This study combines the agronomic characteristics of rice fertilization with weighted coefficient learning-modified single-neuron adaptive proportional–integral–differential (PID) control technology to study and design an aerial real-time variable fertilizer application control system that is suitable for rice field operations in northern China. The nitrogen deficiency at the target plot is obtained from a map based on a fertilizer prescription map, and the amount of fertilizer is calculated by a variable fertilizer application algorithm. The advantages and disadvantages of the two control algorithms are analyzed by a MATLAB simulation in an indoor test, which is integrated into the spreading system to test the effect of actual spreading. A three-factor, three-level orthogonal test of fertilizer-spreading performance is designed for an outdoor test, and the coefficient of variation of particle distribution Cv (a) as well as the relative error of fertilizer application λ (b) are the evaluation indices. The spreading performance of the spreading system is the best and can effectively achieve accurate variable fertilizer application when the baffle opening is 4%, spreading disc speed is 600 r/min, and flight height is 2 m, with a and b of evaluation indexes of 11.98% and 7.02%, respectively. The control error of the spreading volume is 7.30%, and the monitoring error of the speed measurement module is less than 30 r/min. The results show that the centrifugal variable fertilizer spreader improves the uniformity of fertilizer spreading and the accuracy of fertilizer application, which enhances the spreading performance of the centrifugal variable fertilizer spreader.

Dry sliding wear behavior and its relation to microstructure of artificially aged Al-Si-Mg/TiB2 in situ composites

Mechanical stir casting is utilized to produce an artificially aged Al-Si-Mg alloy, whereas halide slat (K2TiF6 and KBF4) synthesis is utilized to produce Al-Si-Mg/TiB2 aluminum matrix composites. The dry sliding pin on disc wear test was conducted using a DUCOM/TR-20LE-PHM-200 machine to simulate an automobile application (Piston-Ring assembly). Where pistons are made of aluminum alloy (for the Pin) and rings are made of grey cast iron (for the disc material). At room temperature, a wear test was conducted by altering the ageing time (3, 6, 9, 12), sliding speed (2, 2.5 m/s), and applied load (14.71, 19.62, 24.52 N) with the disc speed (500 rpm) held constant (10 min). The results indicate that the aluminum matrix composite (AMC) wear rate is reduced by 37 percent at higher sliding speeds (2.5 m/s) and by 4 percent at lower sliding speeds (2.0 m/s) compared to the base alloy. Field emission scanning electron microscope-energy dispersive spectroscopy (FESEM-EDS) and X-ray photoelectron spectroscopy (XPS) analysis revealed that the formation of the mechanically mixed layer (MML) or oxidative layers on the worn surfaces reduces the wear rate under conditions of longer ageing time, higher sliding speed, and lower applied load. The research demonstrates that composite wear is a function of sliding velocity, aging period, and applied force. As sliding speed rose from 2 m/s to 2.5 m/s, the wear rate of composites dropped reasonably, yet composites are softer than basic alloys. It is conceivable due to the presence of a considerable amount of MML and the formation of oxidative layers between pins and their equivalents.

Mechanical and Tribological Behavior of Functionally Graded Unidirectional Glass Fiber-Reinforced Epoxy Composites.

This paper aims to assess experimentally the mechanical and tribological behavior of conventional and functionally graded (FG) polymeric matrix composites reinforced with continuous glass fibers. The small punch test (SPT) and a pin-on-disc device were used in the present work to examine the mechanical and wear behavior, respectively. The hand lay-up technique was used in the present investigation to manufacture the conventional and FG composites. Various wooden looms with different nailed spacing were employed to manufacture the FG composites. According to test type, the FG composite is composed of four and ten layers, with a different glass fiber volume of fraction (Vf%) for each layer. In addition, the finite element simulation based on Hashin’s failure criterion and cohesive zone modeling was used to show the progressive failure and give more explanation regarding the flexural behavior of such composites. The present results indicate that the wear rate of an FG composite could be affected by many factors, including the disk speed, applied load, the composite layers number, and average glass fiber volume fraction. On the other hand, the arrangement of layers in the composite materials by variation of Vf% for each layer can improve the wear rate and value of the ultimate load before the fracture of the composite material when subjected to SPT. The experimental and numerical results for all SPT specimens showed that the fracture of the SPT specimens began beneath the punch tip and grew along the fiber direction. The ultimate flexural capacity of FG composites increased by 30% compared with the conventional composites.

Solvent-antisolvent precipitation in a spinning disc reactor: Precipitation kinetics and mathematical modelling of starch nanoparticles

Experimentally determined kinetics for the precipitation of starch nanoparticles in ethanol antisolvent are reported in a spinning disc reactor. Induction times (tind) obtained from visualisation studies are estimated to be between 13 and 144 ms, with lower tind obtained at higher shear and supersaturations. Nucleation rates are measured to be of the order of 1016 mL−1s − 1, with higher values obtained on a smooth disc at the highest shear conditions and 9:1 antisolvent/solvent ratio. The grooved texture is deemed more advantageous in the low shear regions (i.e. at low flow rate and disc speed) where the passive mixing induced by the flow disrupting grooves produces more nuclei than the smooth surface under similar conditions. Modelling of particle size distribution via population balance equations combined with an engulfment micromixing model has been validated against the experimental profiles with good agreement for most of the conditions studied, even in the presence of agglomerates.

荞麦剥壳机剥壳性能影响因素试验研究

Buckwheat huller is the key equipment of the buckwheat rice processing and its performance is directly related to the quality and yield of buckwheat rice. The key working parts of the sand disc sheller are a pair of parallel sand discs. The structure and the working parameters of the sand discs are the key factors affecting the shelling performance. In this paper, the effect of rotating speed of sand disc, shelling clearance, grain size of sand disc and width of the working face on the shelling performance are experimentally investigated. The results show that the rice yield and relative broken rice rate increase with the increase of the rotating speed of the lower sand disc, and the relative broken rice rate increases sharply when the speed reaches a certain value. With the linear increase of the shelling clearance, the rice yield and the relative broken rice rate are first decreased rapidly, and then decrease slowly. The smaller the particle size of the sand disc is, the higher the rice yield and the relative broken rice rate are, and the influence of the lower sand disc is obviously greater than that of the upper one. Properly widening the width of working face will increase the rice yield but the width tends to have little influence on the rice yield when it increases to a certain extent, and its change has a small impact on the relative broken rice rate. According to the results of single factor test and orthogonal test, the sheller can achieve a better shelling performance and work efficiency when the grain size of the upper sand disc is F24, the grain size of the lower sand disc is F36, the shelling clearance is 5 mm, the rotating speed of the sand disc is 950 r/min, and the width of the working face is 2 cm.

转勺式水稻精量穴直播排种器设计与试验

In order to realize the mechanical direct seeding of precision rows and hills in rice field, a rotary precision hill direct seed-metering device for rice was designed. Through designing the key components of seed-metering device and analyzing its working principle, the main factors and critical conditions affecting the seed-metering performance were obtained. Using the secondary rotation combination test, taking the rotation speed of seed-metering disc and seed capacity height as the test factors, and the re-broadcasting rate, seed-metering qualified rate and miss-seeding rate as the indexes, the seed-metering performance was experimentally studied by using the JPS-12 seed-metering device tested. Design-Expert 6 0.10 software was used to analyze the test data to obtain the mathematical model between factors and indexes. The test results show that when the speed of the seed-metering plate was 24.60 r/min and the seed capacity height was the radius of the seed-metering disc, the qualified rate of seed-metering was 94.83%, the re-broadcasting rate was 3.43%, and the miss-seeding rate was 1.74%. The seeding performance meets the agronomic requirements of rice seeding, and provides a reference for the design of the whole machine.

Design and development of a circular disc type efficient automatic decorticator for Charoli (Buchanania lanzan)

AbstractThe manual decortication process of charoli seeds by beating the dried seeds on the ground with a hand hammer or stone and, by domestic grinder is a laborious, inefficient, time‐consuming as well as uneconomical process. Therefore, an attempt has been taken toward the automation of the charoli decortication process. The decorticator performance was evaluated at three levels of disc speeds, disc clearances, and different moisture levels of charoli seed viz. 197, 246, and 286 rpm; 6, 7, and 8 mm; and 7.83, 8.57; and 9.04% wb, respectively. The selected input parameters were optimized by using the response surface methodology (RSM). The optimum value of disc speed, disc clearance, and seed moisture content was found to be 197 rpm, 7 mm, and 9.04% (wb), respectively. The corresponding response values in terms of decorticating efficiency, whole kernel, and broken kernel percentage at optimum conditions were recorded as 92.5, 21.6, and 3%, respectively.Novelty impact statementThe decorticating capacity of the developed decorticator was found to be 70 kg per hour which was higher than the existing decorticator. Since the developed machine was automatically operated and each unit operation was sequentially and continuously carried out with no manual intervention, the ideal time in each decortication step was absent and subsequently, higher capacity was achieved. The efficiency of the decorticator was found to be 92.5%. The higher capacity and kernel recovery with no human drudgery and lower cost of decortication imply the significance of the development of the machine.

Engineering and Economic Evaluation of a Prototype Fabricated for Harvesting Sugarcane

A sugarcane harvester prototype was fabricated and evaluated to save time, labor, and harvesting expenses, which are included in production costs. The single-row harvester prototype fits the functional needs of the physical qualities of sugarcane and was designed to be installed on a tractor. One serrated edge cutter disc, three forward speeds, and three cutter disc speeds were used to evaluate the performance of the fabricated sugarcane harvester. The results of the technical evaluation showed that the average forward speed was 5 km h−1, and the average cutter disc speed was 2000 rpm by a cutter disc with a serrated edge produced the ideal sugarcane harvesting parameters. The actual field capacity, the power required and the specific energy requirements, were determined. Despite that economic evaluation empathies that the combination of 3.5 km h−1 forward speed and a 1000 rpm cutting speed also achieved the highest benefits ($115.12/ha).

Improving the vertical solar distiller performance using rotating wick discs and integrated condenser

Freshwater is one of the most essential needs of society. Due to the limited amount of potable water on Earth, guaranteeing the supply of clean water to society is a major challenge. By utilizing abundant sunshine, solar still could be utilized to provide the necessary amount of drinking water in remote locations. The issue of restricted daily production inspires researchers to investigate novel ways for enhancing the thermal performance of desalination techniques while lowering expenses. In this work, the scholars improved a unique distillation method related to solar stills. The authors presented a novel improvement to the vertical distiller design to enhance the exposure area while decreasing the thickness of the water layer as much as possible. Thus, two rotational discs (flat type) covered with wick were integrated into the vertical distiller basin at 1.5 rpm and 5 cm water depth. Furthermore, providing vacuum via a fan with an external condenser. Besides, various rotating speeds (from 400 to 2000 rpm) were tested to determine the perfect fan speed that provides the maximum yield. The experimental findings revealed that the modified vertical distiller produced more pure water than the conventional distiller. Moreover, the rotation of wick discs and vacuum fan enhanced the yield of distillers enormously. Besides, the highest distiller performance was obtained at 1.5 rpm (wick disc speed) and 1600 rpm (fan speed, 10 min ON, and 10 min OFF). Moreover, the daily freshwater output was 19.1 L/m2 day for MDSVD without the fan and 23.65 L/m2 day for MDSVD with the fan. So, the yield of MSSVD without/with vacuum fan was improved by 548.65% and 660.45%, respectively, over that of CTD. The best thermal efficacy for MDSVD without/with vacuum fan was 77.47% and 84.05%, respectively. Lastly, the average cost of freshwater was 0.021, 0.0177, and 0.0164 $/L for CTD, MDSVD without/with vacuum fan, respectively.

Effects of disc speed and height of flow mechanism of a solid manure spreader on uniformity of spreading and swath width

The aim of this study was to investigate the effects of disc speed and height of flow mechanism of a solid manure spreader in order to maintain uniformity of spread and swath width for optimum crop growth. The study was done using complete randomized design with three factors considered: tractor forward speed, height of flow mechanism (broadcasters) gate opening rates, (15, 30, 45cm) and disc speed (150, 300, 450rpm) applied according to SAE S341.2, 1999 test code. Results obtained and compared with an imported spreader shows that the developed spreader recorded the highest application rate of 4082.1kg/ha against that of the imported spreader of 1875.3kg/ha while the swath width was 9.5m compared to 9.0m of the imported. Results obtained also shows that the spreader gave a more uniform spread pattern of manure at a lower openning of 15cm height of flow mechanism and lesser disc speed of 150rpm. Disc speed and height of flow mechanism were found to be the major determining factor influencing spreading uniformity and swath width of cow dung manure for optimum crop growth.

Measurement of Heat Transfer and Flow Structures in a Closed Rotating Cavity

Abstract Buoyancy-induced flow occurs inside the rotating compressor cavities of gas turbines. These cavities are usually open at the inner radius, but in some industrial gas turbines, they are effectively closed. This paper presents measurements of the disk heat transfer and rotating flow structures in a closed cavity over a wide range of engine relevant conditions. These experimentally derived distributions of disk temperature and heat flux are the first of their kind to be published. The radial distribution of the nondimensional disk temperature virtually collapsed onto a single curve over the full experimental range. There was a small, monotonic departure from this common curve with increasing Reynolds number; this was attributed to compressibility effects where the core temperature increases as the rotational speed increases. These results imply that, if compressibility effects are negligible, all rotating closed cavities should have a disk temperature distribution uniquely related to the geometry and disk material; this is of important practical use to the engine designer. Unsteady pressure sensors detected either three or four vortex pairs across the experimental range. The number of pairs changed with Grashof number, and the structures slipped relative to the rotating disks by less than 1% of the disk speed.

УПРАВЛЯЕМЫЙ ДВУХДВИГАТЕЛЬНЫЙ ЭЛЕКТРОПРИВОД МАЛОМОЩНЫХ ЦИРКУЛЯРНЫХ ПИЛ

Using low-power circular saws in farm workshops is characterized by the variety of operating modes determined by the nature of cuts. To increase the efficiency of circular saws when cross-cutting wood, use can be made of inertial energy storage devices in the form of flywheels. However, with longitudinal cuts, the kinetic energy of the flywheels quickly dries up, and it takes a long time to replenish it. To reduce the restoration time of the required saw disk speed, the authors propose using the rotor of an auxiliary electric motor as a flywheel. The regulator automatically controls the auxiliary electric motor according to the current value in the power supply circuit of the main electric motor. To avoid self-oscillations of an unacceptably high frequency, the static characteristic of the regulator must contain a section with aт ambiguity zone. This is achieved by using a Ladder Diagram and a logic gate or a microprocessor. The relay-contact circuit includes five electromagnetic relays, a time relay, and two magnetic starters. The time relay aims to eliminate false alarms by ensuring that the regulator is not susceptible to inrush current. To implement the algorithm for controlling an auxiliary electric motor, it is possible to use the logical elements “AND” and “OR,” included according to the proposed scheme. An effective measure of increasing the reliability and reducing the regulator size is the use of the ARDUINO microprocessor together with semistors installed in the power circuits of circular saw motors. The controlled double-motor electric drive of the low-power circular saw reduces energy consumption when cross-cutting wood and improves working conditions and productivity when ripping.

Evaluation of Abrasive WearRate and Machining Behaviors of Synthesized Nitinol Composite

The present investigation deals with wear and machining behaviors of manufacture nitinol composite through Vacuum Induction Melting (VIM). The major composition of nickel and titanium was reinforced with tungsten carbide (WC). Scanning Electron Microscopy (SEM) was employed to investigate the morphology of the synthesized nitinol composite. For investigating the topography of the surface of the nitinol composite was analyzed by scanning force microscopy or atomic force microscopy. Spark erosion machining has been applied to explore the machining behavior of the nitinol composite. Abrasive Wear Rate (AWR) is evaluated by using abrasion tester. Machining and wear parameters are optimized by applying taguchi approach. The contribution and the effect of input constraints on the responses are investigated by analysis of variance.Optimal abrasive wear rate was attained at 900 rpm of disc speed, 12 gm/min of abrasive flow rate and 400m of sliding distance. Disc speed was a dominant factor and it has developed 43.86% effect on abrasive wear rate. Optimal rate of metal removal was achieved at 45A of current, 200µs of pulse on time and 35V of Volts. The current was the leadingfactor and it has produced 86.38% effect on the rate of metal removal.

The impact of centrifugal casting processing parameters on the wear behaviour of Al alloy/Al2O3 functionally graded materials

In this study, a vertical centrifugal casting machine has used for the fabrication of a functionally graded material (FGM) which has prepared by a non-commercial pure aluminium (>97.9% Al) with Al2O3 reinforcement particles were produced at different speeds rang 800 rpm and 1200 rpm. The reinforcement was varied with different volume percentage such as 3, 4.5, 6, and 7.5 vol.% A Pin on the Disc tribometer has used to investigate the sliding wear behaviour of metal matrix composites. The disc speed was kept constant (0.5 m/s) during the wear test, with a load was 30 N at room temperature. The disc as a counter body has made of AISI 52100 steel. For wear testing all specimen has prepared as per the ASTM standards. Establish wear test outcomes have been used the weight loss method across the inward to outward of the cast ring, which depends on the fabrication parameters, sliding distance, velocity, the loading conditions also exhibited in the Scanning Electron Microscopy analysis and micro hardness in that region.

Synthesis and Experimental Investigations of Tribological and Corrosion Performance of AZ61 Magnesium Alloy Hybrid Composites

Magnesium alloy is the light weight material compared to aluminium alloy, and it possesses high strength; these alloys are used to manufacturing of vehicle parts. Magnesium alloy has extreme mechanical and thermal properties, and it is applied to aerospace applications. This study planned to improve the tribological and corrosion resistance of AZ61 magnesium alloy with reinforcement of boron carbide (B4C) and zirconium dioxide (ZrO2). Magnesium alloy hybrid composites are fabricated through stir casting process. Tribological and corrosion performance are analyzed through Taguchi L27 Orthogonal Array. In the tribological analysis, four parameters are involved such as % of reinforcement (4%, 8%, and 12%), disc speed (1 m/s, 2 m/s, and 3 m/s), normal load (30 N, 40 N, and 50 N), and sliding distance (1300 m, 1500 m, and 1700 m). Similarly, in salt spry corrosion analysis, four parameters are influenced used such as % of reinforcement (4%, 8%, and 12%), pH (7, 8, and 9), temperature (30°C, 35°C, and 40°C), and hanging time (30 hrs, 40 hrs, and 50 hrs). From this analysis, percentage of reinforcement is highly influenced in wear test, and in corrosion test, temperature is extremely influenced.

Study on wear behavior of low nickel austenitic stainless steel by using ball on disc

Austenitic stainless steels have wide applications in various industries due to its good corrosion characteristics and their surface strength. A variety of procedures are used to enhance the surface characteristics. Wear studies are critical in all of the toughest materials. Surface damage was studied in terms of material-removal methods such plastic deformation and brittle fracture. This paper investigated the specific wear rate of Low Nickel ASS. The parameters selected for wear testing like sliding speed, load, time duration and types of ball. Six numbers of experiments were conducted for measuring specific wear rate, mass loss and coefficient of friction were highlighted in this paper. A comparison study was made to know the effect of wear parameters like sliding speed, load, time duration and types of ball on specific wear rate and coefficient of friction. It was seen that with increasing of load and sliding speed of disc the specific wear rate of the material significantly increasing.SEM analysis was also made on worn surface to know the behaviour of wear in the sample.

Investigation of microstructural and wear behavior of Al6061 surface composites fabricated by friction stir process using Taguchi approach

The surface composites of aluminum alloys have a higher scope of applications encountering surface interactions in the aerospace, automobile, and other industries compared to the base aluminum alloys. The friction stir process (FSP) is recently the preferred method to prepare aluminum-based surface composites due to its capability to produce improved physical properties and refined microstructure at the surface. The study examines the Al6061 alloy-based surface composite fabricated by FSP for their wear behavior and microstructure. In this study, the Al6061 alloy-based hybrid surface composites are prepared with varying weight% of copper and graphite microparticles mixture as reinforcement by FSP with two tools having unique pin profiles, i.e., threaded cylindrical and plain cylindrical. These prepared composites are investigated for the dry sliding wear test on a pin-on-disc test set-up. The experiments are designed using the L9 orthogonal array and analyzed by the Taguchi approach to obtain the influence of disc speed, load, and reinforcement weight% on wear rate. The significant parameters influencing the wear rate of the samples tested are obtained using ANOVA. Later the effects of the friction stir process and the wear tests on the microstructure of the workpieces are investigated using FE-SEM/EDS tests. It is concluded that the decrease in wear rate with the rise in reinforcement weight% (Cu + graphite) from 2% to 6%. The load has the maximum effect on the wear rate for the samples prepared by threaded cylindrical FSP tool pin profile, while reinforcement weight% affects significantly the wear rate of the samples prepared by FSP with plain cylindrical pin profile tool.

Results of laboratory and bench-scale studies of seed dispensers with an electric drive of working tools

Mechanical and pneumatic seed drills of both domestic and foreign production are used in Russian farms. They are equipped with a mechanical drive of working tools and an electronic seeding control system. Due to the slipping of the wheels or the breakage of the chains, the sowing of seeds in individual seed dispensers interrupts. According to the results of laboratory and bench-scale studies in respect to soybean seeds, the required power for the electric drive of one seed dispenser was determined, which, depending on the disk rotation speed from 10 to 60 rpm, ranged from 30 to 120 W. By calculation, using the analytical expression, the power, required for the fan drive of a 12-row seed drill, was determined, which, depending on the disk rotation speed, ranged from 1.6 to 2.47 kW. A condition is formulated, which will eliminate the probability of shifting and rolling seeds along the furrow after their fall out of the sowing disc rotating in the opposite direction to the movement of the seeder unit, provided correspondence of the linear speed of the sowing disc and the speed of the seeder unit (the effect of zero overlaps). In this case, the trajectory length of the seeds falling to the furrow should be consistent with the speed of the seeder unit and the seeding rate according to the proposed expression.