Rotary Type Research Articles

Performance Test of Arabica Coffee Bean Rating Tool Using Image Sensor Guided

The diversity of coffee bean standards is one of the perspectives of coffee bean quality that is very important to customers. Based on the physical (deffect system) the coffee bean sorting process is divided into two, namely manual sorting and mechanical sorting. The purpose of this study is to study the performance of vibrating table type and conveyor table type rating machines in optimizing time and costs in the process before storage, processing and market to consumers. This research was carried out at the Tanah Toraja Coffee Center, Gandangbatu District, Sillanan District. Tana toraja, the industrial teaching laboratory of the Agroindustry study program, the organolepotic test lab of the Jember research center and the Sukamandi flavcoyur laboratory in the month until March of May 2022. The research method used is linear regression. The best result for the operation of the vibrating table type sorting machine is at a slope of the 8o compartment with a rotating speed of 1,310 rpm with the amount of capacity produced as much as 245 kg per hour and for a rotary table type machine the best result is at a speed of 40 rpm rubber belt speed with a time speed of 30 seconds distance with a distance of 1,800 mm, obtained results on the output hole I ( diameter 7 mm) of 9.2 kg per hour, in the output hole II (diameter 6 mm) of 9 kg per hour, and in the output hole III (diameter 5 mm) of 8.6 kg / hour.

Design optimization of asymmetric wave energy converter using artificial neural network model

The present study aims to improve the mean extracted power of a Wave Energy Converter (WEC) by mapping the parameters of its ballast weight and position, wave frequency, viscosity, and Power Take-Off (PTO) damping using an Artificial Neural Network (ANN) model. A total of 25 types of WEC rotors are designed with varying ballast weights and positions. The hydrodynamic coefficient and response of each rotor are determined using linear potential theory and viscous damping is estimated using computational fluid dynamics. The optimal design parameters are obtained by applying the trained model to a large randomly generated input dataset and the prediction output is evaluated to determine the best design parameters. According to the findings of the study, a well-trained model can predict and adopt to the nonlinear behavior of the given dataset as well as provide the optimal design parameters for the selected pitch-type WEC rotor.

ПАРАМЕТРИЧЕСКАЯ ОПТИМИЗАЦИЯ СИНХРОННЫХ РЕАКТИВНЫХ ЭЛЕКТРИЧЕСКИХ МАШИН

To ensure speed in the operation of electromechanical converters, today a variety of solutions have been taken, both hard-ware and technical. So, to solve the efficient operation of the cold rolling mill KhTP-450, it was decided to use the SRMNV with a gear rotor. The purpose of this article is to consider an alternative to the presented rotor as a non-salient pole rotor of the TLA type. For comparison and identification of optimal geometry, the article presents several rotor solu-tions; the necessary studies were carried out in static mode at different current densities: 4 and 6 A/mm2. The result of the research is a table with the values of the moments for each design, an assessment and corresponding recommendations for use are given.

エンジン要素の熱的な摩擦特性に関する研究 - ピストンリング・シリンダライナの混合・境界潤滑

Similar to vehicle engines, marine engines are required to realize zero emissions of poisonous gas like SOx and GHG like CO2. Therefore, fuels used for future engines will be needed to reduce the content of sulfur and carbon. Under such requirements, the lubricated sliding interface of a piston ring and a cylinder liner often suffers damage, such as excessive wear and scuffing failure, caused by changes in lubrication condition due to in-cylinder combustion and/or fuel-derived substances mixed in the lubricating oil. Given this, appropriate measures are eagerly required to prevent such damage. The thermal friction characteristics of the ring / liner interface under the mixed / boundary lubrication regime during engine break-in procedure are thought to be almost the same as those of cam / tappet under the boundary lubrication regime when using low-viscosity lubricating oil with additives, which was the key subject the authors investigated in their previous study. By analyzing changes in frictional shear stress and the surface temperature and examining a correlation between them, just like the Arrhenius’ equation, it has been clarified that the temperature of the interface displays lubrication functions that can reduce friction, wear and scuffing. Concerning the viscosity and additives of the lubricating oil, the surface roughness of the interface, the ring profile, the contact pressure and the sliding velocity the authors have also investigated how the surface temperature contributed to reducing friction. To this aim, they analyzed the ring / liner data measured with a rotary disk type reciprocating friction test apparatus, which makes it possible to detect the friction force and the ring temperature under the same contact pressure and sliding velocity as those during engine break-in procedure.

Coordinated Rotor-Side Control Strategy for Doubly-Fed Wind Turbine under Symmetrical and Asymmetrical Grid Faults

In order to solve the problems of rotor overvoltage, overcurrent and DC side voltage rise caused by grid voltage drops, a coordinated control strategy based on symmetrical and asymmetrical low voltage ride through of rotor side converter of the doubly-fed generator is proposed. When the power grid voltage drops symmetrically, the generator approximate equation under steady-state conditions is no longer applicable. Considering the dynamic process of stator current excitation, according to the change of stator flux and the depth of voltage drop, the system can dynamically provide reactive power support for parallel nodes and suppress the rise of DC side voltage and rotor over-current. When the grid voltage drops asymmetrically, the positive and negative sequence components are separated in the rotating coordinate system. The doubly fed generator model is established to suppress the rotor positive sequence current and negative sequence current respectively. At the same time, the output voltage limit of the converter is discussed, and the reference value is adjusted within the allowable output voltage range. In order to adapt to the occurrence of different types of power grid faults and complex operating conditions, a fast switching module of fault type detection and rotor control mode is designed to detect the type of power grid faults and voltage drop depth in real time and switch the rotor side control mode dynamically. Finally, the simulation model of the doubly fed wind turbine is constructed in Matlab/Simulink. The simulation results verify that the proposed control strategy can improve the low-voltage ride through performance of the system when dealing with the symmetrical and asymmetric voltage drop of the power grid and identify the power grid fault type and provide the correct control strategy.

Performance of DFIG fed wind turbine under fault conditions

This paper discuss the performance of doubly fed induction generator (DFIG) fed wind turbine system under fault conditions. The proposed performance analysis is demonstrated in MATLAB/Simulation software. A sailent pole rotor type induction generator and three phase converter comprises with IGBT switches are employed to propose the DFIG system. The proposed design has ability to extract utmost energy under minimum wind speed constraints. In order to achieve utmost energy, various control designs such as pitch angle control, wind turbine speed, DC bus potential, grid potential and reactive power control are presented in this paper. The simulation results obtained are helps in understanding the dynamic performance of the DFIG fed wind turbine power generation system.

The Loss and Efficiency Analysis and Research of Interior Permanent Magnet Synchronous Motors for Traction Applications

An IPMSM with I2V type rotor topology structure is proposed, its loss, efficiency and torque are analyzed and compared with V and IV type. Firstly, the optimized rotor topology structures are used to analyze the no-load air-gap flux density waveform and harmonic contents of the IPMSM. The results show that the THD of the no-load air-gap flux density with the I2V type is the smallest and the sinusoidal degree of the waveform is the highest. Secondly, the loss of the IPMSM with optimized rotor topology structures are analyzed and compared. Compared with the other two rotors, the results show that the iron loss of the IPMSM with the I2V type is the smallest. The iron loss of the IPMSM with I2V type is significantly less than that of the other two rotors especially under the deep flux weakening conditions. The output torque of the IPMSM under different current angles, current densities and speed are analyzed and compared. The results show that the torque performance of the IPMSM with I2V type is better than the other two rotors. this paper proposes a simple and effective method to optimize the position and diameter of the magnetic isolation holes by establishing a parameterized model. The results show that the torque ripple and cogging torque with the further optimized I2V type rotor topology structure are greatly reduced, the iron loss and magnet loss are also effectively reduced. Finally, the von Mises stress and the total displacement of the rotor deformation of the IPMSM with the further optimized I2V type under different working conditions are verified by finite element analysis. The results show that the rotor will not rupture, the displacement is small enough to avoid the touch between stator and rotor.

Torque Improvement of Magnet-Assisted Wound Field Motor with Field Unit Type Rotor

Torque Improvement of Magnet-Assisted Wound Field Motor with Field Unit Type Rotor

A Novel Rotor Type Wave Energy Converter Design for Maximum Energy Captured in Low Wave Heights

Wave energy converter system (WEC) is generally used by obtaining of electrical energy. Maximise power capture is needed a range of sea-states. Continuity is improved to control of power take off. But wave energy have o lower force and a higher speed in onhore. Therfore, this paper is investigated the novel rotor type wave energy converter performance in this wave suitable conditional. The performance of this system is tested in laboratory condiotions.This aim of design is maximum power absorption from low wave height of waves. Results show that the higher wave height has caused the efficiency to decrease in all periods. The highest efficiency is obtained at a minimum wave height of 2 cm. At this wave height, the efficiency has reached its highest value when the period is 5 s (20.3%). In this case, it makes this prototype suitable for seas with low wave height and high wave period.

The impact of rotor configurations on hemodynamic features, hemocompatibility and dynamic balance of the centrifugal blood pump: A numerical study.

To investigate the effect of rotor design configuration on hemodynamic features, hemocompatibility and dynamic balance of blood pumps. Computational fluid dynamics was employed to investigate the effects of rotor type (closed impeller, semi-open impeller), clearance height and back vanes on blood pump performance. In particular, the Eulerian hemolysis model based on a power-law function and the Lagrangian thrombus model with integrated stress accumulation and residence time were applied to evaluate the hemocompatibility of the blood pump. This study shows that compared to the closed impeller, the semi-open impeller can improve hemolysis at a slight sacrifice in head pressure, but increase the risk of thrombogenic potential and disrupt rotor dynamic balance. For the semi-open impeller, the pressure head, hemolysis, and axial thrust of the blood pump decrease with increasing front clearance, and the risk of thrombosis increases first and then decreases with increasing front clearance. Variations in back clearance have little effect on pressure head, but larger on back clearance, worsens hemolysis, thrombogenic potential and rotor dynamic balance. The employment of back vanes has little effect on the pressure head. All back vanes configurations have an increased risk of hemolysis in the blood pump but are beneficial for the improvement of the rotor dynamic balance of the blood pump. Reasonable back vanes configuration (higher height, wider width, longer length and more number) decreases the flow separation, increases the velocity of blood in the back clearance, and reduces the risk of blood pooling and thrombosis. It was also found that hemolysis index (HI) was highly negatively correlated with pressure difference between the top and back clearances (r=-.87), and thrombogenic potential was positively correlated with pressure difference between the top and back clearances (r=.71). This study found that rotor type, clearance height, and back vanes significantly affect the hydraulic performance, hemocompatibility and rotor dynamic balance of centrifugal blood pumps through secondary flow. These parameters should be carefully selected when designing and optimizing centrifugal blood pumps for improving the blood pump clinical outcomes.

Characteristics Evaluation of a Segmental Rotor Type Switched Reluctance Motor with Concentrated Winding for Torque Density and Efficiency Improvement

With the rapid development of power electronic techniques and the increasing cost of permanent magnets (PMs) materials, switched reluctance motors (SRMs) have recently gained more attention. However, traditional SRMs have a relatively low torque density. For the sake of increasing the motor torque density, this paper proposes a novel segmental rotor type SRM. The proposed motor adopts hybrid stator poles and concentrated windings in the stator side and a segmental rotor structure in the rotor side, which is completely different from the structures of the traditional SRM. The special structure of the motor shortens the magnetic flux paths of the motor, separates the parts of the magnetic flux paths from one another, and eradicates the magnetic flux reversal in the motor stator in order to improve the electric utilization and output torque density of the motor. Meanwhile, the requirement of the magneto-motive force and the core loss of the motor is also decreased, thereby improving the efficiency of the motor. For the purpose of proving the proposed structure, the characteristics of the motor are analyzed using the finite element method and are compared to those of the traditional 12/8 SRM, which is designed for the same application. Moreover, the prototypes of the traditional 12/8 and proposed SRMs are manufactured, and experiments based on the prototypes are performed. Finally, the effectiveness of the structure of the proposed motor is further proven by the experimental results.

Numerical investigation of 3D unsteady flow around a rotor of vertical axis wind turbine darrieus type H

This article presents an analysis of the complex and unsteady flow a ssociated with the functioning of the rotor of a vertical axis wind turbine Darrieus - H. In this study, the influence of different numerical aspects on the accuracy of the simulation of the flow around a rotor of three straight blades in rotation is performed, which are the effect of the turbulence modeling, and the effects of the mesh and the time step. The Delayed Detached Eddy Simulation (DDES) approach is used. The aim of this article is to describe and analyze the unsteady flow in 3D predicted numerically considering the effects of arms like blade-arms interference, blade-wake interactions around the Darrieus rotor and the effect of tip vortices. Two-dimensional simulations are used in a preliminary numerical configuration. Then, three-dimensional simulations a re performed t o p recisely determine the characteristics of the complex aerodynamic flow associated with the operation of the wind turbine rotor. The flow field around the rotor is studied for several values of the tip speed ratio, dynamic quantities, such as the torque and the power of the rotor that are presented and analyzed. From the results obtained, it is clear that the approach of the Detached Eddy Simulation with the SST K-ω model can be considered as a reliable prediction. A comparison of the performance of the results showed that the predicted coefficients of performance are very close to the experimental data from the bibliography.

Abstract 12792: Reentrant Drivers Are Distinguished From Passive Rotors by Sequential Computer Simulation of Ablation Using Personalized Non-Paroxysmal Atrial Fibrillation Heart Models Based on Late Gadolinium Enhancement Magnetic Resonance Imaging (LGE-MRI)

Introduction: Although rotor modulation targeting atrial fibrillation (AF) drivers or substrates has been proposed as one of the effective ablation strategies for non-paroxysmal AF (Non-PAF), previous meta-analyses demonstrated that ablation added to pulmonary vein isolation (PVI) did not result in the expected outcome. This is because the optimal method of detection of rotors and ablation strategy remain unclear. Recently, rotor detection using LGE-MRI-based computer simulations has been shown to be effective for Non-PAF ablation in clinical practice. Our study aimed to establish the minimal ablation strategy that, while correctly finding the rotors, also avoids iatrogenic atrial tachyarrhythmias due to excessive ablation. Hypothesis: By prioritizing and classifying detected rotors, reentrant drivers (RDs) of AF rather than passive rotors (PRs) could be identified, thereby offering an optimal ablation strategy. Methods: Personalized computational modeling of AF ablation was performed in 10 Non-PAF patient models based on fibrosis data from LGE-MRI. In each bi-atrial model, all rotors induced outside of PVI were investigated, and a number of ablation strategies were examined sequentially to classify rotors and achieve minimal ablation (figure). A rotor that terminated following ablation of another rotor was defined as PR. A rotor that persisted and needed to be ablated to achieve non-inducibility of the substrate was defined as RD. Results: Seven patients had rotors outside of PVI, with 6 having both PRs and RDs. Overall, 35 rotors were induced, 13 in left atrium and 22 in the right; 17 were RDs and 18 PRs. In addition, the density of fibrosis in the sites of RDs was significantly higher than in those of PRs (p=0.031). Conclusion: The sequential computer simulation strategy to predict ablation targets using a personalized AF model is promising in detecting different types of rotors and establishing the optimal minimum-lesion ablation strategy.

Abstract 15219: Optogenetic “Printing” of Reentrant Arrhythmias in Human Induced Pluripotent Stem Cell Derived Cardiac Tissues

Introduction: Current models used to investigate reentrant arrhythmias allow for limited control of arrhythmia parameters and morphology. Here, we developed a method for the induction of morphologically and physiologically defined arrhythmias using human induced pluripotent stem cell derived cardiac cell sheets (hiPSC-CCSs) and optogenetic tools. Methods: One million hiPSC-cardiomyocytes expressing the optogenetic channel CoChR were used to create the hiPSC-CCSs. Rotor illumination patterns were generated either by computer-aided design or by utilizing previously recorded rotor patterns. A digital micro mirror device (DMD) and a 470nm LED were used to project five complete cycles of these rotor patterns onto the hiPSC-CCSs. Results: Optical projection of typical rotors led to repeated development of arrhythmias in all sampled tissues (n=11). The resulting arrhythmias resembled the projected rotor patterns in terms of directionality (clockwise or counterclockwise) and number of cores ,and were highly reproducible for each projection (Fig.1A). Interestingly, we identified a minimal and maximal frequency of the projected rotor that could induce arrhythmias (Fig.1B). Moreover, the frequency of the generated rotor could not be increased beyond a certain value despite further increases in the projected rotor frequency (Fig.1B). Lastly, to assess the effects of tissue EP properties, the process was repeated after treatment with the IKr blocker E-4031 (30nM). E-4031 treatment significantly reduced the minimal and maximal frequencies of the projected rotor that could still induce arrhythmia and slowed the maximal frequency of the resulting rotor (Fig.1B). Conclusions: We present a new method for the optical induction of reentrant arrhythmias allowing the generation of rotors rapidly, reproducibly, and with a predesigned morphology. This approach may allow for a paradigm shift in the way reentrant arrhythmias are studied.

DEVELOPMENT OF FINITE ELEMENT ANALYSIS PROGRAM FOR ROTORDYNAMIC PREDICTION OF SINGLE AND MULTI DISK ROTOR MODEL

The rotating equipment is a crucial part of system performance reliability. Vibration, as a characteristic of an oscillating body, is a fundamental parameter to determine the dynamic behaviour of the rotor system. The dynamic characteristics include natural frequency, critical speed, mode shape, and vibration response. This paper discussed the application of rotordynamics analysis as a tool to numerically predict the dynamic behaviour of a rotor system. The aim is to determine a rotor system's natural frequency and critical speed by a finite element analysis (FEA) program. The selected method is validated using various analytical methods from other references with small discrepancies in the result. The calculation of FEA using the computational program; they applied the developed program to describe the dynamic characteristic of single and multi-disk rotors. The developed works provided comprehensive results about a rotor system's natural frequency, mode shape, and critical speed and predicted the vibration response due to unbalance. However, other types of rotors, such as coaxial dual rotors, can be further investigated to make the program capable of the general purpose of the rotor. Validation with the real case problem could be an interesting investigation to satisfy the result of developed works.

Field Survey on Generation Patterns of Airborne Fungi in a Livestock Manure Composting Plant in South Korea

Airborne fungi emitted from livestock manure composting plants are one of the major harmful factors causing respiratory disease for workers and nearby residents. Their generation of emissions is relatively high compared to other workplaces. This study investigated the emission characteristics of airborne fungi generated in livestock manure composting plants and utilized them as basic data to prevent workers’ health. The livestock manure composting plants selected for the survey in this study were according to the fermentation mode, including screw type, rotary type and natural dry type. The field evaluation period was from September 2019 to August 2020 and was surveyed monthly. The equipment for collecting airborne fungi was a six-stage cascade impactor. An analysis of the quantification and qualification of airborne fungi was conducted through a culture method and identification technique, respectively. The mean levels of airborne fungi in livestock manure composting plants were 1143 (±106)CFU m−3 for screw type, 552 (±146)CFU m−3 for rotary type and 434 (±73)CFU m−3 for natural dry type, respectively. Based on the results obtained from this study, the livestock manure composting plant operated by screw type showed the highest concentration of airborne fungi, followed by the rotary type and natural dry type. The monthly concentration of airborne fungi was the highest in June and the lowest in February, regardless of the livestock manure composting plant type. The concentration range of airborne fungi corresponding to the respiratory particle diameter was 40 to 60% relative to the concentration of all airborne fungi. The correlation relationship between airborne fungi and environmental factors (temperature, relative humidity, particulate matter and odor) was not found to be significant in livestock manure composting plants. The predominant genera of airborne fungi identified were Aspergillus spp., Cladosporium spp. and Penicillium spp.

Study on the Improvement of Fire-Fighting Tactics for the Stable Supply of Fire Extinguishing Water

The connected water pipe facility is an important fire extinguishing facility for supplying fire water to firefighters on the fire floor. However, there are cases where fire water is not supplied quickly, which is also caused by the inability to find the connection water pipe inlet owing to unclear regulations on the installation location of the connection water pipe facility fire safety standards. If the connected water pipe facility is not found, fire-fighting tactics involving ropes are used, which takes a lot of time. To improve this problem, we confirmed experimentally that fire extinguishing water can be quickly and stably delivered to fire suppression personnel using a water outlet (40 A) installed in an indoor fire extinguishing tank on the first floor of an apartment. Through the experimental results, the Fire Safety Standards (NFSC 502) for Connected Water Pipeline Facilities (NFSC 502) proposed a plan to improve the fire safety standards (new) that require installation of water outlets (65 A, rotating) in the indoor firebox on the first floor of the apartment. If the revised fire safety standards are applied to the new building, firefighters who arrive at the site can quickly and stably supply fire water through the connecting water pipe connection port (65 A, rotary type) installed in the indoor fire extinguishing tank.

Analisa Perbandingan Pengasutan Motor Induksi 3 Fasa Soft Starter IGBT Berbasis Sine-Triangle dan Sine-Sawtooth PWM Menggunakan Matlab Simulink

<em>T<em><span>The induction motor is the electric drive for industry so special attention is needed for maintainance and control system. Induction motors pulling high starting currents at starting. Various starting methods have been developed to overcome this problem, one of which is the Direct On-Line starting method. This method is the most common method because it is the easiest and cheapest to use, but there is high inrush current arround 6-8 times the nominal current will pulled by induction motor when using this method. This starting current can cause several disturbances, both from the electricity network, damaging the motor and can cause fatal losses to the electric power system.This research discusses the application of the Soft Starter starting method to a 3-phase induction motor to reduce the high starting current pulled by a 3-phase induction motor. The induction motor used in this study is a squirrel cage rotor type with 4kVA power, a rotational speed of 1430 r.p.m, a frequency of 50 Hz, and a voltage of 380 V. The Soft Starter system in this study uses 6 Insulated Gate Bipolar Transistor </span><span lang="IN">(</span><span>IGBT</span><span lang="IN">)</span></em><em><span>power electronics switches which are controlled using a sine-triangle PWM and sine - Sawtooth PWM. MATLAB SIMULINK is used to simulate the application of the soft starter starting method on a 3-phase induction motor.The results prove that the Soft Starter method is successful in reducing staring currents when compared to the Direct On-Line method. When using the Direct On-Line method the starting current is 77.29 – 78.80 A, when using the sine-triangle soft starter method the starting current is 60,46 – 61,46 A, and when using the sine-sawtooth soft starter method. starting 59,96 – 60,60 A. However, at steady state conditions, the Direct On-Line rotational speed is better than the Soft Starter because when using the Soft Starter method the voltage is cut. Soft St</span></em></em>

Rubbing vibration characteristics of double-rotor system under wave load

Structural characteristics of a certain type of gas turbine double rotor and its hull are analyzed. The wave of a regular form is considered, and the wave load is simplified to the form of sinusoidal force. The rubbing force and nonlinear supporting force of the bearing are deduced as per the Hertz contact theory and Coulomb friction law. The mechanical model of the double rotor system under the combined action of the wave load and rotor friction impact is established, which is solved by the fourth-order Runge-Kutta method. The bifurcation diagram, phase diagram, Poincare section diagram, axis trajectory diagrams, effects of rotor eccentricity, and friction coefficient on the nonlinear dynamic characteristics of the system under rub impact fault are studied. The obtained results show that with an increase in eccentricity, the system enters into a chaotic state through the period doubling and paroxysmal bifurcations, and successively experiences nonlinear behaviors such as periodic 2 bifurcation, periodic 4 bifurcation, and quasi periodic and chaos. In the double rotor system, the nonlinear dynamic behavior of the single period and semi Nermark-Sacker bifurcation occurs with increasing friction coefficient. The present findings can provide a theoretical basis for condition monitoring, fault diagnosis, and design optimization of this type of gas turbine double rotor system.

Coaxiality and perpendicularity prediction of saddle surface rotor based on deep belief networks

Purpose Aiming at the problem that the transmission mechanism of the assembly error of the multi-stage rotor with saddle surface type is not clear, the purpose of this paper is to propose a deep belief network to realize the prediction of the coaxiality and perpendicularity of the multi-stage rotor. Design/methodology/approach First, the surface type of the aero-engine rotor is classified. The rotor surface profile sampling data is converted into image structure data, and a rotor surface type classifier based on convolutional neural network is established. Then, for the saddle surface rotor, a prediction model of coaxiality and perpendicularity based on deep belief network is established. To verify the effectiveness of the coaxiality and perpendicularity prediction method proposed in this paper, a multi-stage rotor coaxiality and perpendicularity assembly measurement experiment is carried out. Findings The results of this paper show that the accuracy rate of face type classification using convolutional neural network is 99%, which meets the requirements of subsequent assembly process. For the 80 sets of test samples, the average errors of the coaxiality and perpendicularity of the deep belief network prediction method are 0.1 and 1.6 µm, respectively. Originality/value Therefore, the method proposed in this paper can be used not only for rotor surface classification but also to guide the assembly of aero-engine multi-stage rotors.