The Taguchi optimization method is an efficient method for motor design optimization. However, it is hard to handle the multiobjective motor optimization problem with big design space for the ...parameters. To deal with this problem, in this article, a fuzzy method and sequential Taguchi method to optimize an inter permanent magnet synchronous motor (IPMSM) is employed. The fuzzy inference system is introduced to convert the multiple objectives to a single-objective optimization problem. The sequential Taguchi method is used to optimize the structural parameters at multiple levels to improve the accuracy of optimization. After the optimal selection analysis, the best combination of motor structure factors is obtained. By comparing the optimization result of the proposed method with that of the conventional Taguchi optimization method, the effectiveness and superiority of the proposed method are verified.
This article investigates the efficient robust design optimization of a five-phase permanent magnet (PM) hub motor for electric vehicles. Besides the requirement of high-performance, like high torque ...density, low torque ripple and efficiency, fault-tolerant operation capability are also considered in the design optimization. To ensure that the motor performance is not sensitive to the variations of manufacturing tolerances, robust design optimization is employed to the investigated motor. To improve the fault tolerant capability of the motor, the motor performances under fault operation are also considered in the optimization. A Fuzzy-based sequential Taguchi robust optimization method is proposed to improve the comprehensive performance and save computing time. The proposed method is efficient because it holds the advantages of Taguchi method, fuzzy theory, and sequential optimization strategy. The motor performance is improved significantly by using the proposed method. Experimental results verify the accuracy of the model used in this study.
The present research focuses on the synthesis of high-purity nickel powder through solution-based chemical reduction using hydrazine hydrate as a reducing agent. A series of synthesis experiments ...were carried out with variations in the concentration ratio of hydrazine to nickel ions (N2H4/Ni2+ = 5–15), the concentration ratio of hydroxyl ions to nickel ions (OH−/Ni2+ = 10–20), temperature (T = 60–80 °C), and reaction time (t = 30–90 min). The Taguchi L9 design of experiments and analysis of variance (ANOVA) was used to identify the role of the hydroxyl-to-nickel ion ratio (OH⁻/Ni2⁺) in determining the apparent purity of the nickel powder. The highest apparent nickel powder content, which was 92.75 %, was obtained in the experiment with N2H4/Ni2+ = 5, OH−/Ni2+ = 12.5, T = 60 °C, and t = 30 min. The optimum conditions that significantly influence the apparent purity of nickel powder derived from data processing are used as the basis for the second stage of the experiment to determine the effect of the OH−/Ni2+ ratio on particle size, morphology, and purity of the synthesized nickel powder. It was found that higher hydroxyl concentrations lead to finer particles, and the morphology of nickel particles is linked to their apparent purity, with the chain of beads of nanoparticle aggregates morphology achievable when OH−/Ni2+ = 12.5 and OH−/Ni2+ = 15. The presented results may contribute to filling the gap in the knowledge to synthesize high-purity nickel powder with controlled size and morphology, which can be used in various applications such as catalysts, conductive fillers, and advanced electrodes.
•High-purity Ni powder was succesfully synthesized via a solution-based chemical reduction using hydrazine hydrate.•Higher hydroxyl concentrations produce finer particle sizes.•The particle morphology is related to its purity.•Nanoparticle aggregates morphology achievable at OH−/Ni2+ = 12.5 and OH−/Ni2+ = 15.
This paper presents the optimization of cutting forces, average surface roughness, cutting temperature, and chip reduction coefficient in turning of Ti-6Al-4V alloy under dry and high pressure ...coolant (HPC) that is applied at the rake and flank surfaces simultaneously. The experimental design plan was conducted by the full factorial parameter orientation. The optimization has been conducted in two ways: firstly, by using signal-to-noise ratio-based Taguchi method as mono-objective optimization; secondly, by using gray relational analysis integrated with Taguchi method as multi-objective optimization. In either method, the cutting speed, feed rate, and cutting condition were considered as the inputs to the optimization. The mono-objective optimization concluded that the 156 m/min cutting speed and 0.12 mm/rev feed rate when run under HPC optimized the cutting forces and roughness, and when operated under dry optimized chip reduction coefficient, the cutting temperature was minimized at 78 m/min and 0.12 mm/rev feed rate. The multi-objective optimization concluded that Ti alloy turning system is optimized at 156 m/min cutting speed and 0.12 mm/rev feed rate under HPC.
The present work illustrates the parametric effects on biodiesel production from Hevea brasiliensis oil (HBO) using flamboyant pods derived carbonaceous heterogeneous catalyst. Activated carbon (AC) ...was prepared maintaining 500 °C for 1 h and steam activated at optimised values of activation time 1.5 h and temperature 350 °C. Carbonaceous support was impregnated with KOH at different AC/KOH ratios. The transesterification process was optimized and significant parameters affecting the biodiesel yield was identified by Taguchi method considering four parameters viz. reaction time, reaction temperature, methanol to oil ratio and catalyst loading. The physicochemical properties of Hevea brasiliensis methyl ester (HBME) were examined experimentally at optimised condition and found to meet the global American standards for testing and materials (ASTM). The optimum condition observed to yield 89.81% of biodiesel were: reaction time 60 min, reaction temperature 55 °C, catalyst loading 3.5wt% and methanol to oil ratio 15:1. Contribution factor revealed that among four parameters considered, catalyst loading and methanol to oil ratio have more prominent effect on biodiesel yield. The cost for preparing carbonaceous catalyst support was estimated and observed to be fairly impressive. Thus, Hevea brasiliensis oil (HBO) could be considered as suitable feedstock and flamboyant pods derived carbon as effective catalyst for production of biodiesel.
•Study of parametric effects on transesterification of HBO by carbonaceous catalyst.•Taguchi method with L9 orthogonal array was used for optimization of the process.•Catalyst loading was emerged as most influential parameter.•Cost analysis of catalyst revealed that it is cost effective and eco-friendly.•Biodiesel was characterised following ASTM standards.
•This is the first attempt for producing biodiesel from Styrax officinalis L. oil as a novel and non-edible feedstock.•Optimization of four considerable effective parameters of transesterification of ...the new oil via Taguchi technique.•L9 orthogonal array of the Taguchi approach could help to mitigate clearly the number of the experimental runs.•Notification on the biodiesel production under optimized reaction conditions and its physicochemical properties.•Most of the fuel characteristics of the biodiesel satisfy the global biodiesel standard of EN 14214.
The development of renewable and sustainable candidates for petroleum-based fuels is needed to address the present issue of the increasing fuel crisis regarding transportation, environmental pollution, and consumption of the petroleum reserves. In addition, there is a need to explore new non-edible oils for biodiesel production due to problems such as fuel versus food as well as procurement and presence. Therefore the experimental research was carried out to synthesize biodiesel from Styrax officinalis L. oil. It has been firstly investigated and reported as a novel feedstock for the production of alternative fuel. The raw material was subjected to esterification at desired reaction parameters estimated by 9-runs (L9) orthogonal approach of Taguchi technique. Noteworthy, the oil content was found to be at 48.29 ± 3.81%. The maximum biodiesel yield of 89.23% was obtained under the following optimized conditions: catalyst concentration of 0.6 wt%, methanol to oil molar ratio of 6:1, reaction duration of 60 min and reaction temperature of 60 °C. The detection of the substantial parameters was achieved using the Taguchi method and the significant parameters were obtained as follows: catalyst concentration, methanol to oil molar ratio, reaction duration, and reaction temperature with contribution factors of 78.07%, 20.32%, 0.42%, and 1.19%, respectively. Statistical analysis employing ANOVA exhibited that emerged outcomes are in good agreement with the predicted values. The fuel properties of the methyl esters from Styrax officinalis L. oil were within the ranges of the EN 14214 specifications. Therefore, the novel seeds can be a suitable feedstock for biodiesel production in the nearest future.
•Presents a statistical approach for investigation of progressive tool wear.•The effect of cutting parameters on tool wear were analyzed with ANOVA.•AE sensor and dynamometer were evaluated for ...detection of tool breakage.•Taguchi based prediction was compared with experimental results.•Optimization of machining parameters during turning were obtained.
On-line monitoring of tool wear and tool breakage are very important to reduce production costs through the optimization of machining parameters. Increasing cutting forces affect workpiece quality and tool condition that is the ultimate aim of production line and progressive tool wear which can trigger the tool breakage. Taguchi method is extensively used for determining number of experiment while variance analysis (ANOVA) deals with which parameter/s is/are effective on output. This study contains experiments and optimization processes during turning of AISI 1050 material with 3 input parameters (cutting speed, feed rate, tool tip) using Taguchi method. In order to determine the condition of the cutting tool, measurement of tangential cutting force and acoustic emission (AE) were carried out during metal removing. ANOVA results showed that cutting speed is the most effective about %45 and tool tip is the second about %35 on tool wear. On the other hand, the effect of feed rate on tangential cutting force (%88) and cutting speed on AE (%80) is remarkably higher than the other two parameters. In order to obtain the minimum tool wear value, the optimum cutting parameters have been selected as v1 = 135 m/min, f2 = 0,214 mm/rev, T2 = P25. By implemented sensor system tool breakage can be successfully detected and used for producing high quality materials with low costs.
Alongside the progress in technology related to the Internet of Things, the Mahalanobis-Taguchi (MT) system, which is an anomaly detection technique suitable for monitoring the condition of ...production equipment, has attracted attention. However, with the conventional MT method, historical data acquired and accumulated from sensors and smart devices cannot be analysed appropriately. This is because very often the accumulated historical information is data not labelled as either 'normal' or 'anomaly'. Therefore, in this research, we propose a procedure that enables to detect anomalies with the MT method even when learning data are categorised as 'unlabelled'. Specifically, we introduce a process for estimating the Mahalanobis distance on the population by applying a robust method based on γ divergence in the MT method. Through numerical experiments, we show that the proposed procedure is a useful anomaly detection technique for unlabelled data. Since this implies that labelling is redundant in anomaly detection, we conclude that the practicality of the MT method can be improved.
In today’s wood industry, research is being conducted to increase material strength, ensure long-term use, and increase its hardness against many harmful external factors. With the studies on the ...protection of wood, new protection materials and methods are introduced. In this study, wood was etched with solid sodium bicarbonate (NaHCO3) and 1, 2, and 3 bars of air pressure after treatment with NaHCO3 solution and drying. The change in hardness values of impregnated and surface-treated (paint, varnish) chestnut wood after artificial aging was examined. Etching, impregnation, and surface treatment factors were optimized using the Taguchi design of experiments (DoE) after artificial aging for 3, 6, and 9 months. L16 orthogonal array was used to determine the optimum conditions for determining hardness values and their percentage changes. The results showed that the abrasive factor prevails over the effect of surface treatments. It has been understood that the most effective factor in the hardness value changes during the artificial aging period (3-6-9 months) is abrasion, and the factor with the least effect is the surface parameter. The percentage accuracy of the model used in estimating the wear factor average R2 across all dependent variables was 95%.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
•CFD and the Taguchi method are utilized in the optimal design of a VAWT.•The interactions between serration and helical blade angle are accurately predicted.•Power coefficient increases by 18.3% in ...the optimal design.•The optimal serration amplitude and wavelength are 2.5% and 1/6 of cb, respectively.•The optimal blade helical angle is 60°.
The flow performance of vertical-axis wind turbines (VAWTs) is significantly deteriorated by dynamic stall at low tip-speed-ratios (TSR). Dynamic stall occurs periodically during the rotation of turbine blades and generates flow separations formed at leading-edges, which results in tremendous fluctuations in torque and essential reduction in power outputs. The target of this study is to apply a combination of CFD and Taguchi method to optimize the aerodynamic performance of a typical three-bladed VAWT at a low TSR of 2. Leading-edge wavy serrations and helical blade structures are implemented as the design parameters and the performance of these designs are compared with a corresponding baseline straight blade design of a traditional H-type VAWT. A comprehensive simulation study is carried out to obtain detailed flow characteristics. The Taguchi method is applied to find out the optimal combination of the selected factors such as amplitude and wave length of the serrations and twist angle of helical blade. A modified additive model is used to include the interaction effects among the selected factors. The optimal combination is found to appear in the case with an amplitude of 2.5%cb (cb is the blade chord length) and a wavelength of cb/6 for leading-edge serration as well as a blade twist angle of 60°. The simulation results show that the flow separations and torque fluctuations are significantly suppressed due to the passive flow control strategies implemented in the optimized VAWT model. The power output of the optimized wind turbine is found to increase by 18.3% in comparison to the baseline model. In addition, the force fluctuations are observed to be significantly reduced by employing the helical design, which is beneficial for improving the lifespan of turbines. The results derived from this study indicate a better VAWT design for the rural and built environments with relatively insufficient wind energy.
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