Orthogonal Array Design Research Articles

Effect of Laser Treatment on the Surface Roughness of Multilayer Plasma Sprayed Thermal Barrier Coating System

Thermal barrier coatings (TBCs) are used in advanced engines working at higher temperatures. Higher efficiency and performance of gas turbine engines will require careful selection of TBCs. In this study, Ni22Cr10Al1.0Y (Amdry 9625) bond coat and two types of top coat including ceria stabilized zirconia (CSZ) ZrO2-24CeO2-2.5Y2O3) and yttria stabilized zirconia (YSZ) ZrO2-8Y2O3 were deposited on IN 625 by air plasma spraying (APS). The thickness of the duplex ceramic coat based on zirconia was in the range between 350 to 400 µm. The effect of high power Yb:YAG solid state laser at different laser parameters on feature, microstructure and roughness of plasma sprayed and laser sealed coating of multilayer ceria stabilized zirconia/ yttria stabilized zirconia was investigated. Surface roughness has been reduced significantly after laser sealing. The effect of laser process parameters carried out using Taguchi’s L16 orthogonal array design. Minimum roughness can be obtained at moderate power density and longer interaction time with sufficient specific energy to produce complete melting of coating. Characterization and analysis of results was achieved by employing scanning electron microscopy (SEM) , (EDS) and image J analysis. It was found from the results, there were significant improvements in the performance of plasma sprayed coatings after laser sealing due to the reduction of surface coating defects.

Wide-scope multi-residue analysis of pesticides in beef by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

Increasing pesticide contamination in foods of animal origin has made the wide-scope multi-residue analysis of pesticides an international concern. In this study, a sensitive and reliable multi-residue pesticide analysis method for beef was developed with the use of 129 pesticides to demonstrate the full scope of the method. The pesticides were extracted and purified using a modified QuEChERS technique and analysed using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. An orthogonal array design was employed for optimisation of the method, significantly scientising and simplifying the process. Method validation revealed satisfactory sensitivity with limits of quantification values ranging from 0.003 to 11.37 µg∙kg−1. Matrix effects ranged from 83.85% to 120.66%. Recovery at three spiking levels (20, 50, and 100 µg∙kg−1) were 70.51–128.12% and the intra-day and inter-day precisions were less than 20%, indicating good accuracy and precision.

Two-step leaching process and kinetics for an eco-friendly recycling of critical metals from spent Li-ion batteries

With growing awareness to protect the urban environment and fulfill the soaring demand for critical metals, recycling of postconsumer Li-ion batteries has become imperative to deal in a sustainable manner. In this context, a two-step leaching of the exhausted LiNixCoyMnzO2 cathode material was studied by sequential application of both organic and mineral acids. To optimize the experimental parameters of both steps, leaching was conducted using the L25 orthogonal array design. In the first-step leaching, lithium and copper was selectively leached into oxalic acid at the optimal condition of C2H2O4 (OA), 0.25 M; pulp density (PD1), 10%; H2O2 dosage (HPD1), 0.5%; temperature (T1), 80 °C; and time (t1), 90 min. The parametric influences for achieving more than 99% efficiency of lithium and copper followed the order: t1 > HPD1 > OA > PD1 > T1 and t1 > T1 > OA > HPD1 > PD1, respectively. Residual metal-oxalates of cobalt, nickel, and manganese were subsequently dissolved into sulfuric acid solutions. Approximately 99% of all remaining metals could be leached at the optimal condition of H2SO4 (SA), 3.0 M; pulp density (PD2 -), 6%; H2O2 dosage (HPD2), 2%; temperature (T2), 60 °C; and time (t2), 120 min. The parametric influences on sulfuric acid leaching of metals followed the order as: SA > HPD2 > t2 > PD2 > T2. Leaching followed logarithmic rate law and exhibition of the diffusion-controlled mechanism was revealed through the values of apparent activation energy determined to be Ea(Li), 9.7 kJ/mol; Ea(Cu), 22.3 kJ/mol; Ea(Co), 9.5 kJ/mol; Ea(Ni), 11.2 kJ/mol; and Ea(Mn), 6.2 kJ/mol. This study successfully demonstrated the applicability of OA in the selective leaching of LiNixCoyMnz-type cathode materials, eliminating the need for copper and lithium separation from leach liquor of SA-medium. The present process offers two-fold advantages that securing the secondary supply for critical metals, and providing an environmentally sustainable route for waste valorization in a circular economy.

Heat transfer and pressure drop characteristics of 3-D finned tube heat exchanger in ash-laden flue gas

As an efficient heat transfer enhancement element, 3-D finned tube has good potential in the field of waste heat utilization of industrial flue gas. However, the industrial flue gas often contains a large amount of ash particles. Meanwhile, ash deposition on the surface of heat exchanger can worsen the heat transfer performance and even shorten the service life of the heat exchanger. Therefore, the research of coupling effect of heat transfer and ash deposition on 3-D finned tube heat exchanger is very necessary, and it is bound to affect the further promotion and application of 3-D finned tube heat exchanger. In this paper, the influence of ash deposition on heat transfer process of 3-D finned tube heat exchanger was further studied. The effects of ash deposition time on heat transfer rate and relative pressure drop were discussed firstly. It was found that both ofheat transfer and relative pressure drop basically tended to be stable with the running time up to 6 hours. Then, the influences of fin height of 3-D finned tube, gas velocity and particle concentration on fouling characteristics, heat transfer and flow performance were studied according to the orthogonal array design method. The optimized parameters corresponding to the smallest fouling coefficient and the least relative pressure drop after fouling were determined. Besides, the performance of 3-D finned tube heat exchanger with the optimized parameters was also compared with other tested heat exchangers. The results showed that the heat exchanger with optimized parameters had better heat transfer performance than the other cases under the same condition. At last, a correlation of fouling coefficient of 3-D finned tube heat exchanger under the optimized parameters with ash deposition time was obtained, and it can be useful in the design and evaluation of heat exchanger in dusty environment.

Process optimization of microwave irradiation‐aided transesterification of kariya seed oil by Taguchi orthogonal array: pawpaw trunk as a novel biocatalyst

AbstractThis study investigated the potential application of an active biocatalyst from pawpaw (Carica papaya) trunk for the direct microwave irradiation‐aided transesterification of kariya (Hildegardia barteri) seed oil (KSO) with methanol to obtain biodiesel. The transesterification process involved was modeled, and the effects of the essential process input variables on the kariya seed oil methyl ester (KSOME) yield were examined, followed by the optimization of the input variables to maximize the KSOME yield, using the Taguchi orthogonal array design method. The biocatalyst was produced with a calcination process in a muffle furnace at 200–1000 °C, and each sample obtained was characterized by a scanning electron microscope equipped with energy‐dispersive X‐ray spectroscopy (SEM–EDX) to determine the best temperature. The calcined pawpaw trunk ash (CPTA) produced at the best temperature of 400 °C was further characterized using X‐ray diffraction (XRD), Fourier‐transform infrared (FTIR) spectroscopy, and physisorption analyses. The CPTA at 400 °C produced a strong catalytic activity due to its morphology, metallic composition (K (23.85%), and Ca (15.40%)), crystalline structure, the average pore size of 32.2 nm, and a surface area of 0.64 m2 g−1. The best operating conditions established for the transesterification process were a methanol / KSO molar ratio of 10.5:1, CPTA loading of 0.5 wt%, microwave heating power of 300 W, and reaction time of 2 min, with a maximum KSOME yield of 98.50 ± 0.60 wt%. The quality of the KSOME produced satisfied the American standard specifications for biodiesel. Both KSO and pawpaw trunk could serve as inexpensive feedstock for sustainable and renewable production of biodiesel. The intensification of the transesterification process using microwave irradiation drastically shortened the reaction time needed for maximum biodiesel yield. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

Finite Element simulation and Optimisation of blank holder force and rectangular drawbead geometry using Taguchi method for hemispherical cup

In sheet metal forming process for obtaining good component one of the important practices is to controlling the sheet material flow into the die cavity. This is possible by applying the proper blank holding force and optimized drawbead geometry on the surface of the die.This paper aims to investigate the effect of drawbead geometry and blank holding force on thickness of formed component and restraining force using the Taguchi optimized technique. FE simulation is carried out by hyperform software and L9 orthogonal array design of experiments is used for simulation. Furthermore the values of thickness and drawbead forces predicted by developing a linear regression model. From the result, it is noticed that the shoulder radius and drawbead height are more influencing parameters for controlling the restraining force and thickness variation. The obtained results are validated by conducting conformation test and values obtained are the good agreement with the literature data and simulated results.

Investigation of Durable Bio-polymeric Antimicrobial Finishes to Chemically Modified Textile Fabrics Using Solvent Induction System

New technologies and materials required for developing antibacterial textiles have become a subject of inter¬est to the researchers in recent years. This study focuses on the investigation of the biopolymeric antibacterial agents, such as neem, aloe vera, tulsi and grapeseed oil, in the trichloroacetic acid-methylene chloride (TCAMC) solvent used for the pretreatment of polyethylene terephthalate (PET) polyester fabrics. Different PET structures, such as 100% polyester, polyester/viscose, polyester/cotton and 100% texturised, are treated with four different concentrations (5%, 10%, 15% and 20%) of biopolymeric antibacterial finishes. The antibacterial activity of the treated samples is tested against both the Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) bacteria. Taguchi mixed orthogonal array Design L16 (4^3 2^2) is chosen for an experimental plan to determine the optimum conditions. Among all the fabric samples, the 100% polyester fabric treated with 20% grapeseed oil registers the highest antibacterial activity of 86%, and 73% against S. aureus and E. coli respec¬tively. However, the antibacterial effect is reduced to 37%, and 34% respectively after 10 machine launderings.

Iterative estimation of Sobol’ indices based on replicated designs

In the field of sensitivity analysis, Sobol’ indices are widely used to assess the importance of the inputs of a model to its output. Among the methods that estimate these indices, the replication procedure is noteworthy for its efficient cost. A practical problem is how many model evaluations must be performed to guarantee a sufficient precision on the Sobol’ estimates. The present paper tackles this issue by rendering the replication procedure iterative. The idea is to enable the addition of new model evaluations to progressively increase the accuracy of the estimates. These evaluations are done at points located in under-explored regions of the experimental designs, but preserving their characteristics. The key feature of this approach is the construction of nested space-filling designs. For the estimation of first-order indices, a nested Latin hypercube design is used. For the estimation of closed second-order indices, two constructions of a nested orthogonal array design are proposed. Regularity and uniformity properties of the nested designs are studied.

Photocatalytic Degradation of Antibiotics and Dyes in Wastewater by Hydrogenated Black Titanium Dioxide Nanoparticles Using Design of Experiment L9 Taguchi Orthogonal Array

Photocatalytic Degradation of Antibiotics and Dyes in Wastewater by Hydrogenated Black Titanium Dioxide Nanoparticles Using Design of Experiment L9 Taguchi Orthogonal Array

Experimental investigation on electrical discharge machining of steel H13

Abstract Electrical Discharge Machining (EDM) is being used to machine components made out of hard alloys and are geometrically complex in shapes. Different types of materials like tool steels, composites, carbides and super alloys are difficult to machine by conventional machining process can be machined by EDM. But this process still has some limitations during machining of hard alloys like tool steel (H13). This material finds application in various types of industries such as tool and die, nuclear and aerospace etc. In this research paper, simultaneous optimization of output parameters over cut and material removal rate is done using desirability approach. Orthogonal array (L18) design was used to perform the EDM experiment on H 13 steel.

EDM machining characteristics of bamboo leaf ash and alumina reinforced aluminum hybrid metal matrix composite using Multi-response optimization by grey relational analysis

In this research work, aluminum hybrid composites using bamboo leaf ash (BLA) and alumina have been fabricated via stir casting. Three hybrid composites viz: A713 + 2%BLA + 2%Al2O3, A713 + 2%BLA + 4%Al2O3, A713 + 4%BLA + 2%Al2O3 are fabricated successfully and EDM machining of these three composites is performed. The EDM machining experiments of the three hybrid composites, have been designed using Taguchi L27 orthogonal array design of experiments (DOE) considering current (A), duty cycle (%), gap voltage (V) and different percentage composition of the reinforcements. The effect of the EDM machining process parameters on the output responses such as surface roughness (Ra) and material removal rate (MRR) are evaluated using grey relational analysis.

Using the Taguchi Method and Grey Relational Analysis to Optimize the Performance of a Solar Air Heater

Solar energy is regarded as one of the promising renewable energy sources in the world.The main aim of this study is to use the Taguchi-Grey relational grade analysis to optimize the performance of two Solar Air Heaters (SAHs). A typical Grey–Taguchi method was applied. The Orthogonal Array, Signal-to-Noise ratio, Grey Relational Grade, and Analysis of Variance were employed to investigate the performance characteristics of SAH. Experimental observations were made in agreement with Jordanian climate 32°00′ N latitude and 36°00′ E longitude with a solar intensity of 500 W\m2. The operating factors selected for optimization are the tilt angle (T) with three levels (0°, 22°, 45°), inlet velocity (V) with two levels (1.2, 1.8 m/s), and absorber plate material (M) with two levels (Aluminum, wood). In this study, the Grey–Taguchi approach is validated by performing 12 individual experiments. The results show that the process factors sequence required for a maximum SAH efficiency (SAH µ) is V > T > M. Using this approach, we combined the Orthogonal Array design with Grey Relational Analysis. As a result of that, the level of each operating conditions which optimizes both process responses (Temperature difference, ∆T and Solar air heater efficiency, SAH µ) can be specified with a minimum number of tests compared with classic Grey Relational Analysis. The optimal operating conditions of a SAH for multiple performance characteristics are determined as T2, M2, and V2, respectively, which are in congruence with the experimental results.

Parametric studies on SiC-abrasive jet assisted machining of alumina ceramics

Abstract Present study investigates machinability of K-90 alumina ceramic for Fluidized-Bed Abrasive Jet Machining (FB-AJM) in presence of Silicon Carbide (SiC) abrasives. Four input process factors such as pressure, standoff distance, abrasive temperature, and abrasive mesh size are considered associated with L16 orthogonal array design of experiment. Effects of AJM parameters on output responses viz. Material Removal Rate (MRR), Overcut (OC), and circularity error (deviation) are studied. In addition, Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) integrated with Taguchi method is applied to determine the most appropriate setting of AJM parameters in purview of maximum MRR, minimal OC, and minimal circularity error.

Taguchi Optimization of Catalytic Ozonation Process Using Modified Bone Char Ash for Removal of Methylene Blue from Aqueous Solution

Methylene blue (MB) dye is an environmental contaminant that has been mostly used in textile industry. Taguchi orthogonal array design was employed as an optimization method to reduce the number of experiments. In this research, bone char ash modified by MgO-Fe catalyst was applied for degradation of MB in catalytic ozonation process (COP) system and operational parameters including initial MB dosages, initial pH, catalyst dose, and contact time were optimized with Taguchi method. Accordingly, the best condition for the removal of MB obtained at initial MB concentration of 20 mg/L, reaction time of 15 minutes, initial pH value of 10, and catalyst concentration of 0.1 g/L. Additionally, optimization of experimental set-up showed that the MB concentration had a notable effect on MB degradation in COP process (55.6%), and reaction time had a negligible effect (1.98%). At this condition, total organic carbon (TOC) removal was determined to be 31% but in longer time, its removal increased to 65%.

Optimization of erosion wears of Al–Mg–Si–Cu–SiC composite produced by the PM method

Abstract Metal matrix composites are expanding their range every day due to their various industrial applications in manufacturing sectors, to attain high performance and favorable characteristics such as light weight, more excellent corrosion as well as wear resistance, high specific strength and high temperature-resistance than conventional materials. This study deals with analysis on erosion wear characteristic and corrosion behavior of newly-engineered aluminum metal–matrix composite (Al–0.5Si–0.5Mg–2.5Cu–5SiC) developed by powder metallurgy method. Solid particle erosion test was conducted on the newly developed AMMC product and the execution of design of experiments through Taguchi and statistical techniques demonstrates the feasibility of investigating the erosion characterization and behaviors of the composites. Sixteen set of experimental trials were performed by considering three process parameters (impact angle, stand-off distance, and impact velocity) associated with four levels each. Experimental results in accordance of Taguchi’s orthogonal array design of experiments are analyzed by employing analysis of variance (ANOVA), response surface methodology (RSM) and desirability function approach for analysis, predictive modeling and optimization of erosion rate, respectively. Thereafter, an observation on eroded surface morphology is performed under the influence of impact velocity by employing scanning electron microscope (SEM) to entrench the process. Result shows that, the impact velocity followed by impact angle have significant contribution (80.42 and 8.71%, respectively) in improvement of erosion rate. The methodology proposed in this study collects the experimental results and builds a mathematical model in the domain of interest and optimized the process model. Under the highest desirability (1), desirability-function approach of RSM presented the optimal manufacturing conditions at impact velocity of 18 m/s, stand-off distance of 26 mm and impact angle of 67° with estimated erosion rate of 65.155 mg/kg. The experimental data generated for Al–0.5Si–0.5Mg–2.5Cu–5SiC AMMC will be useful for the industry.

Parameter Optimization of ASSAB XW 42 Tool Steel on End Milling Process with MQCL Using Taguchi-WPCA

Determination of a combination of process variables that are not appropriate in the end milling process will result in high surface roughness and can reduce the metal removal rate. Therefore, it is necessary to adjust the end milling process variables with the appropriate minimum quantity cooling lubrication. This study aims to obtain a combination of end milling process variables on ASSAB XW-42 material using the Taguchi-WPCA method to minimize arithmetic roughness (Ra), quadratic roughness average (Rq), and average roughness from peak to valley (Rz), and maximize metal removal rate (MRR) simultaneously. The cooling fluid method used is the minimum quantity of cooling lubrication (MQCL). The end milling process variable that is varied is the cutting fluid (soluble oil and vegetable oil), spindle speed (178 rpm, 310 rpm, and 570 rpm), feed rate (33.5 mm / minute, 59.4 mm / minute and 111.9 mm / minute) and the cutting depth (0.125 mm, 0.25 mm and 0.5 mm). The cutting tool used in this study is solid carbide end mill having four cutting edges with a diameter of 10 mm. The experimental design of the L18 orthogonal array was used in this study. The results showed that the optimal roughness of the workpiece surface and metal removal rate (MRR) was given by vegetable oil cutting fluid, 570 rpm of spindle speed, 33.5 mm / minute of feed rate, and 0.25 mm of the cutting depth. The Cutting fluid, spindle speed, and feed rate have a significant effect on the response variables observed simultaneously.

Optimization of Fluconazole Pickering Emulsion Using Taguchi Orthogonal Array Design

Emulsifier-free, particle-stabilised emulsions called Pickering emulsions of fluconazole for topical delivery, were studied using Taguchi L9 orthogonal array (OA) design. Formulations were prepared by homogenization method, using bentonite in the concentration range of 2-4% w/v, oil phase (coconut oil, oleic acid, sesame oil). In Taguchi L9 OA experimental design, independent variables (oil phase & concentration of bentonite) effect on dependent variables (drug content & release rate) was studied. All the formulations have shown good physicochemical properties. The PS3 formulation containing sesame oil and 4% bentonite was optimized as particle size was found to be 758.0 nm, zeta potential -48 mv, with Q8 of 166.70±0.15μg/cm2, flux of 17.33±0.02 μg/cm2/hr, permeability coefficient of 3.46±0.015 cm/hr×10-3 and skin content of 4.01±0.24 mg/g. The formulations were stable and non-irritant. Hence pickering emulsion of fluconazole using sesame oil can be used for topical delivery as the drug release was maintained at the localised site.
 Dhaka Univ. J. Pharm. Sci. 19(2): 169-178, 2020 (December)

Alkali Treatment Effect on Physicochemical and Tensile Properties of Date Palm Rachis Fibers

ABSTRACT This work aims to optimize the physicochemical and tensile properties of vascular fibers extracted from a local date palm rachis in Algeria. This fiber has a very specific composition and architecture and is different from the remaining fibers obtained from the six possible parts of the tree. For this purpose, a Taguchi orthogonal array design L16 was applied to reduce the number of experiments. The fibers were extracted from the rachis with two different methods (boiling and retting in water) and treated by NaOH with various concentrations (1%, 2%, 3%, and 5%) and for different durations (1, 4, 8, and 12 h). They were characterized using SEM-EDX, ATR-FTIR, XRD, and TGA to understand the effects of the extraction method and alkali treatment. A statistical treatment of the data was carried out based on the S/N ratio and ANOVA was performed to identify the most significant parameters affecting the tensile strength and the Young’s modulus of the fibers. A desirability function was developed to identify the optimal factors leading to the maximization of the tensile properties.

The Experimental Process Design of Artificial Lightweight Aggregates Using an Orthogonal Array Table and Analysis by Machine Learning.

The purpose of this study is to experimentally design the drying, calcination, and sintering processes of artificial lightweight aggregates through the orthogonal array, to expand the data using the results, and to model the manufacturing process of lightweight aggregates through machine-learning techniques. The experimental design of the process consisted of L18(3661), which means that 36 × 61 data can be obtained in 18 experiments using an orthogonal array design. After the experiment, the data were expanded to 486 instances and trained by several machine-learning techniques such as linear regression, random forest, and support vector regression (SVR). We evaluated the predictive performance of machine-learning models by comparing predicted and actual values. As a result, the SVR showed the best performance for predicting measured values. This model also worked well for predictions of untested cases.

Microencapsulation of zinc by spray-drying: Characterisation and fortification

Zinc sulphate heptahydrate was microencapsulated by spray-drying using maltodextrin, HI-CAP® 100 and whey protein isolate as wall materials. Spray-drying conditions were optimised using Taguchi orthogonal array design with encapsulation efficiency and bulk density as responses. The influences of wall material, wall material to zinc ratio and inlet air temperature were evaluated. Microcapsules prepared with HI-CAP® 100 in 20:1 loading ratio at 185 °C had maximum encapsulation efficiency (92.65%), whereas 10:1 ratio yielded maximum bulk density (541.2 kg/m3). SEM micrographs revealed the spherical structure of microcapsules, while EDX confirmed the presence of zinc in the microcapsules. SEM micrographs, FTIR and XRD analyses showed that zinc was successfully encapsulated as microcapsules. The tapped, bulk and particle densities of zinc microcapsules were in the range of 586.15–698.15, 437.40–541.20 and 1263.25–1436.50 kg/m3, respectively, while flowability was ‘fair' to ‘passable’. The adsorption isotherm of microcapsules was sigmoidal, and was described by GAB model. Fortification of milk with zinc microcapsules did not affect its inherent organoleptic qualities.