Showing papers in "Journal of The Institution of Engineers : Series C in 2020"
TL;DR: In this article, the Gray Taguchi technique was used for the quality and mechanical characteristics enhancement of Nylon and the results from the test sample printed at the determined optimum setting has exhibited tensile strength of 51.455 MPa, flexural strength as 98.12 MPa and compression strength as 18.42 MPa.
Abstract: Fused deposition modelling (FDM) is one such technique of additive manufacturing (AM) that deposits the extruded thermoplastic material layer by layer to build the desired part. The study is focused on the introduction of new thermoplastic material that widens the application of FDM process and also to use the part for functional purpose rather than just the prototype. Nylon is used as the feed filament material for FDM due to its higher mechanical properties and wear resistant characteristics that are often used as sliding bearing. The properties of nylon are further enhanced by adding the aramid short fibres. In this investigation, the process parameter optimization of FDM process is performed by using Gray Taguchi technique for the quality and mechanical characteristics enhancement. Layer thickness, print temperature, raster angle, infill part density and infill pattern style were considered as the influencing factors for optimization. Mechanical properties including tensile strength, flexural strength, impact strength and compression strength (responses) were studied for the designed experiments which were conducted according to ASTM standards. Analysis of variance was performed using Minitab 18 software to understand the signal-to-noise ratio for the respective objective. The overall combined objective is framed by providing equal importance to all the four responses. From the analysis, the following factors were identified as the optimum settings, layer thickness of 0.4 mm, print temperature of 300 °C, infill part density of 90%, raster angle of 90° and infill pattern style of rectilinear. The results from the test sample printed at the determined optimum setting has exhibited tensile strength of 51.455 MPa, flexural strength as 98.164 MPa impact strength of 0.637 MJ/sq m, compressive strength as 19.42 MPa. The test result of the parts printed from pure nylon as per the prescribed standard setting exhibited tensile strength of 48 MPa, flexural strength as 80.5 MPa, impact strength as 0.51 MJ/sq m and compression strength as 18.12 MPa. A significant increase by 7.2% in tensile strength, 22.7% in flexural strength, 27.4% in impact strength and 7.5% in compressive strength were noticed. From the investigation, it was possible to conclude that even short fibre composites can also be used as FDM raw materials and valid predictions can be made using regression equations with very less error and is justified by experimental trails.
29 citations
TL;DR: A comparative study of artificial neural network (ANN) and support vector machine (SVM) using continuous wavelet transforms and energy entropy approaches for fault diagnosis and classification of rolling element bearings shows that SVM gives the better fault diagnosisand classification accuracy than ANN.
Abstract: The research paper presents a comparative study of artificial neural network (ANN) and support vector machine (SVM) using continuous wavelet transforms and energy entropy approaches for fault diagnosis and classification of rolling element bearings. An experimental test rig is used to acquire the vibration signals of healthy and faulty bearings. Four real-valued base wavelets are considered. Out of these wavelets, mother base wavelet is selected on behalf of maximum energy and minimum entropy criterions and extracts the statistical features from wavelet coefficient of raw vibration signals. These statistical features are used as input of ANN and SVM for classifying the faults of bearings. Finally, Morlet wavelet is selected on the basis of energy and entropy criterions. The test results show that SVM gives the better fault diagnosis and classification accuracy than ANN.
27 citations
TL;DR: In this paper, a new cooling approach was proposed by combining two sustainable machining techniques, that is, the usage of surface textured tools under the minimum quantity lubrication (MQL) environment.
Abstract: Machining of bearing steel material such as AISI 52100 steel is one of the challenging fields in the metal cutting industries due to the high hardness which results in low productivity and high manufacturing cost. To overcome these issues, in the present work, the new cooling approach was proposed by combining two sustainable machining techniques, that is, the usage of surface textured tools under the minimum quantity lubrication (MQL) environment. In the experimental investigation, three types of cutting tools were considered, among that two were surface texture tools, namely surface texture grooves 45° inclined to the main cutting edge tool and circular perforated holes tool, and third is a nontexture tool. Taguchi analysis was carried out to study the effect of different surface texture tools and process parameters on turning performance during machining of AISI 52100 steel under MQL cooling condition. From the Taguchi analysis, optimum cutting conditions were determined for obtaining the low surface roughness and tool flank wear, respectively. Also, it was concluded that surface texture grooves 45° inclined to the main cutting edge tool type significantly reduced the surface roughness and tool flank wear, respectively.
26 citations
TL;DR: In this article, the authors analyzed the government policies, programs, and incentives to enhance and develop the solar-wind sector in India, alongside potential limitations and solutions, and reviewed the development of offshore wind, which is slated to be added to the energy mix of the country over the coming decade.
Abstract: Being among the most populated country with one of the fastest growing economies in the world, the country is met with ever-increasing fossil fuel consumption. The use of fossil fuels for energy is threatening India with emission pollutants, the import burden of crude oil and natural gas, and coal resource extinction. Clean energies have long been thought to reduce or eliminate a country’s dependence on fossil fuels for electricity generation. In the past decade, India has made major additions to its renewable energy capacity, especially with respect to solar and wind, which represent a major proportion of renewable generation in the country. This paper analyzes the government policies, programs, and incentives to enhance and develop the solar–wind sector in India, alongside potential limitations and solutions. It also reviews the development of “offshore wind,” which is slated to be added to the energy mix of the country over the coming decade.
17 citations
TL;DR: In this article, an attempt was made to identify the optimized parameter combination in abrasive jet machining of Inconel 718 alloy based on L9 Taguchi array, where pressure, standoff distance and abrasive flow rate were considered as input parameters.
Abstract: In this work, an attempt was made to identify the optimized parameter combination in abrasive jet machining of Inconel 718 alloy. Experiments were conducted based on L9 Taguchi array. Pressure, standoff distance and abrasive flow rate were considered as input parameters. M18 standard washer of 20 mm inner diameter and 34 mm outer diameter was made on a sheet of thickness 2 mm. The qualities of the washer were measured with respect to roundness, taper angle, material removal rate and surface roughness. Improved compromise ranking method also known as VlseKriterijumska Optimizacija I Kompromisno Resenje in Serbian (VIKOR) method was used in this work to identify the optimized parameter combinations. Experiment number 7 with 180 MPa pressure, 0.42 kg/min abrasive flow rate and 2 mm standoff distance was identified as the best parameter combination.
16 citations
TL;DR: In this article, the authors present a technique for designing and investigating the strength of a composite blade on an example of a mine ore ventilation fan, considering aerodynamic loads acting on a blade airfoil surface.
Abstract: The paper presents a technique for designing and investigating the strength of a composite blade on an example of a mine ore ventilation fan, considering aerodynamic loads acting on a blade airfoil surface. The technique is based on the use of the finite element method in a combination with the theory of multilayer shells to determine the dynamics and strength of the composite airfoil, as well as the methods of the computational fluid dynamics, namely the Reynolds equations, for modeling an air movement in a fan passage to determine aerodynamic loads. A static strength estimation is based on an application of the Hashin strength criterion. An analysis of the results of strength calculations considering aerodynamic forces indicates a necessity of accounting them for thin-walled composite elements. A possibility of varying a thickness of the shell and taking it into account using the presented method allows to achieve an optimal ratio of strength and weight indices. A buckling analysis of the composite shell under an action of complex loading, based on methods of the linear stability theory, as well as calculations of natural frequencies and natural frequencies with regard to a prestressed state from an action of static loads, completes the technique. The results of the research allow to conclude on an applicability of the presented methodology for analyzing the strength of composite blades and an efficiency of the proposed design of the airfoil, as well as a possibility of its use to create real rotary machines.
14 citations
TL;DR: In this article, the influence of cutting speed, feed rate and machining environment on the performance of hybrid Al stacks was investigated in the context of carbon fiber/glass fiber reinforced aluminum (Al) stacks.
Abstract: Carbon fiber/glass fiber-reinforced aluminum (Al) stacks are becoming predominant in the aerospace industries owing to their synergistic effect on numerous properties obtained by the combination of metal and composite material. This necessitates an investigation work to be performed on the machining characteristics of this special category of Al stacks. This research work focuses on studying the influence of cutting speed, feed rate and machining environment on thrust force, delamination and roughness of the finished surface of hybrid Al stacks. Dry, minimum quantity lubrication (MQL), and cryogenic environments are considered in this work. The impact of cutting speed on the responses is observed to be negligible in contrast to the feed rate. Moreover, the drilling under cryogenic environment is found to improve the surface finish and mitigated the delamination, while drilling under MQL environment minimized the thrust force. Regression models are also developed to determine the output responses. High-quality holes in aluminum stacks can be obtained under cryogenic conditions over other machining environments as revealed by multi-objective optimization.
14 citations
TL;DR: In this article, a review of multiphase LBM models is presented and the advantages and limitations of these models have been explained by considering the application field, including cavitation phenomenon, cavitation rise or droplet fall, Rayleigh-Taylor instabilities, coalescence of bubbles or droplets, wettability and contact angles.
Abstract: With the simplicity and robustness of the lattice Boltzmann method (LBM), it is getting more attention nowadays in the multiphase flow applications. Different models of multiphase flow studies are available in LBM. Theory and applications of lattice Boltzmann multiphase models R–K color gradient, Shan–Chen (SC), Free energy (FE) and He–Chen–Zhang (HCZ) approaches have been discussed in this review. The methodologies of these methods have been explained in details. Besides, the advantages and limitations of these models have been explained by considering the application field. Based on the applications in the multiphase flows, recent developments in these models have been explained. The major applications of LBM in multiphase flows are flow through porous media, cavitation phenomenon, bubble rise or droplet fall, Rayleigh–Taylor instabilities, coalescence of bubbles or droplets, wettability and contact angles. An effort has been made to explain the methodologies for the multiphase LBM. Modified R–K color gradient model is more accurate and less efficient. SC model is more efficient and less accurate. FE model is numerically more accurate and less efficient. HCZ model more efficient and more accurate. The efficiency of modified R–K color gradient and free energy models almost similar.
14 citations
TL;DR: An improved multi-objective ant lion optimization technique has been applied to obtain the optimal trajectory with minimization time-jerk–torque rate for a 6 axis Kawasaki RS06L industrial robot.
Abstract: In this paper, an optimal robotic trajectory planning subjected to kinematic and dynamic constraints has been described. The kinematic parameters like jerk and dynamic parameters like torque rate mainly influence the smoothness of the travel of robot end effector along the trajectory path. Therefore, these parameters are to be constrained for reducing the robot positional error, but it leads to vast increase in total travel time of robot which in the end affects the productivity. Therefore, an improved multi-objective ant lion optimization technique has been applied to obtain the optimal trajectory with minimization time-jerk–torque rate for a 6 axis Kawasaki RS06L industrial robot. After implementation of the algorithm, the torque rate and jerk have been reduced considerably and the total travel time before and after optimization has been found to be 34.38 s and 28.21 s.
11 citations
TL;DR: In this paper, a free-vibration analysis of epoxy-based cross-ply laminated composite folded plate structures under hygro-thermal stresses is performed for variations in layup, hygrothermal loads, crank angles and plate thicknesses.
Abstract: This research involves free-vibration analysis of epoxy-based cross-ply laminated composite folded plate structures under hygro-thermal stresses. Finite element analysis has been employed with eight-noded Mindlin-type isoparametric plate elements and rotary inertia. A 6 × 6 transformation matrix is applied to transform the element matrices before assembling the system matrices. This requires implanting a small diagonal element representing in-plane rotation along the five usual displacements. Parametric studies have been performed for cross-ply laminated folded plate structure. All-edge clamped one- and two-fold folded plates are studied for variations in layup, hygro-thermal loads, crank angles and plate thicknesses. Results reveal that increasing hygro-thermal load reduces the stiffness of the structure considerably. Stiffer sections can withstand higher temperature and moisture content than thinner sections. Presence of ridge line in folded plates make the structure stiffer compared to flat plate and hence capable of resisting higher hygro-thermal load.
11 citations
TL;DR: In this article, a double-effect passive solar still is designed for experimental investigations to determine the freshwater collected at the output channel, and a two-phase, three-dimensional model of the unit is developed in ANSYS FLUENT for the transient state to simulate various temperatures inside the solar still and to estimate the production rate of distilled water produced.
Abstract: Even though water is a renewable resource, most of the water present on the earth’s surface is not suitable for direct human consumption. Besides, due to increasing population, urbanization, environmental pollution and growth of industries, the requirement for pure water is found increasing day by day. Also, natural resources of water can meet freshwater demand to only to a limited extent. Hence, there is a need to find a way to purify saline water with the help of an effective water desalination technique. Solar still is one such method which makes use of naturally available sunlight to purify impure/saline water. In this paper, a double-effect passive solar still is designed for experimental investigations to determine the freshwater collected at the output channel. Also, a two-phase, three-dimensional model of the unit is developed in ANSYS FLUENT for the transient state to simulate various temperatures inside the solar still and to estimate the production rate of distilled water produced. The simulation was run for 8 h, and the results have been compared with the experiment performed. Experimental investigations show a total distilled output of 3.2 L/m2 collected in channel, whereas according to analysis results, 3.74 L/m2 output is observed. Here, simulation results follow the similar trend as the experimental results and show good agreement with each other.
TL;DR: A modified path matrix approach was presented in order to compare all the distinct geared kinematic mechanisms of epicyclic gear trains and their mechanisms and found satisfactory results with existing literature.
Abstract: The identification of isomorphism in epicyclic gear trains has been found a lot of attention by researchers for the last few years. Various methods have been suggested by different authors for the detection of isomorphism in planer kinematic chains and epicyclic gear trains (EGTs), but everyone has found some difficulties to address new issues. In this paper, a modified path matrix approach was presented in order to compare all the distinct geared kinematic mechanisms. A new method based on the matrix approach and corresponding train values is required to identify isomorphism among epicyclic gear trains and their mechanisms. The proposed method was examined on the basis of various examples from four-link, five-link, six-link, and eight-link one-degree-of-freedom EGTs and six-link two-degree-of-freedom EGTs. All the examples have been found satisfactory results with existing literature.
TL;DR: In this paper, the performance of different segmentation methods for segmentation of banana leaf disease images was compared and the results showed that the geodesic method had significantly lower mean square error (MSE), peak signal-to-noise ratio (PSNR), and structural similarity index measure (SSIM) than all other methods.
Abstract: Identification and classification of leaf diseases in banana crop are an important requirement for farmers to diagnose and to get proper remedies for the pest and disease infection Development of an automated system using image processing for leaf disease identification reduces time, cost and mainly supports to increase the productivity of banana fruit In this process of automation, image segmentation is a key component that is required to analyze the image and to extract information from it Image segmentation is a low-level module of image processing used to segregate the required object from an image for further analysis The performance accuracy of image segmentation module determines the success of higher-level module of image processing Therefore, to select an appropriate segmentation method for leaf analysis, different segmentation methods like adaptive thresholding, canny, color segmentation, fuzzy C-means, geodesic, global thresholding, K-means, log, multithresholding, Prewitt, region growing, Robert, Sobel and zero crossing are analyzed and compared in this paper The quantitative matrices such as mean square error (MSE), peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) are considered to measure the performance of different segmentation methods The results showed that geodesic method had significantly lower MSE value (6610), PSNR value (6608) and higher SSIM value (0196) than all other methods It is concluded that geodesic method is better for segmentation of banana leaf disease images
TL;DR: In this article, the authors investigated the physical and chemical properties of binary and ternary biodiesels with respect to time and compared the degradation of physical properties of the pre-processed biodiesel.
Abstract: Milk scum is a waste obtained in milk dairies, which can be used as a raw material for producing biodiesel by a transesterification process In this research study, the biodiesel obtained from milk scum was blended with diesel to make binary blends (B20D80, B60D40 and B100) These binary blends were further blended with ethanol in different percentages to make ternary blends (B20E05D75, B20E10D70, B20E15D65) Physical and chemical properties of binary and ternary blends were investigated and compared Degradation of physical properties of the prepared biodiesels with respect to time was studied, which is the salient part of the work Engine performance test was conducted in a single-cylinder diesel engine Performance of the engine for different blends (both binary and ternary) was recorded and compared Addition of 5% ethanol showed a decrease in fuel consumption, whereas higher content (15%) of ethanol showed rapid increase in fuel consumption as compared to that of binary blends Ternary blend containing 5% ethanol showed higher brake thermal efficiency (BTE) compared to D100 (diesel only), while ternary blends containing 10 and 15% ethanol gave lower BTE compared to 5% ethanol and D100 The blend B20E05D75 is considered as better alternative fuel upon comparing mass fuel consumption, air fuel ratio and brake thermal efficiency with all rest of blends tested in this study
TL;DR: In this article, the effect of three different input factors such as feed (8, 16, and 22.4mm/min), speed (710, 1400, and 2000-rpm), and drill geometry (8-facet, dagger, and slot drill) on the drilling forces (thrust force and torque) was studied.
Abstract: In this study, the biodegradable composite (unidirectional bamboo fiber/polylactic acid) was developed by means of film stacking technique in a hot compression molding setup. The drilling characteristic of the biodegradable composites was experimentally studied by varying different factors. The effect of three different input factors such as feed (8, 16, and 22.4 mm/min), speed (710, 1400, and 2000 rpm), and drill geometry (8-facet, dagger, and slot drill) on the drilling forces (thrust force and torque) was studied. The signals of drilling-induced forces were found to be different for the different drill geometries studied. The slot drill induces minimum forces (thrust force and torque) while making a hole in the composites among all drill geometries. The experimental results reveal that drilling-induced forces reduce at high spindle speed and low feed.
TL;DR: In this article, the XRD analysis was carried out to check the uniform distribution of beryl particles and chemical composition of the MMC and the experimental results revealed that tensile strength, hardness and toughness were determined.
Abstract: Aluminum MMC is being enormously used in automotive and aerospace applications because of their enhanced mechanical properties. Commonly used MMCs are alloys of aluminum, magnesium, titanium and iron. Particulate reinforcement of Al MMCs includes silicon carbide, boron carbide, tungsten carbide, graphite, etc. Aluminum MMCs reinforced with ceramics like neodymium, yttrium, cerium, Pr praseodymium, beryl, etc., are finding a lot of importance. In the current work, investigation of the mechanical properties of Al2024 with beryl as the reinforcement is being carried out. The composites were prepared by stir casting technique. Mechanical properties like tensile strength, hardness and toughness were determined. Microstructural studies and XRD analysis were carried out to check the uniform distribution of beryl particles and chemical composition of the MMC. The experiments were conducted for As-cast and annealed samples. The experimental results revealed that UTS and hardness increased with an increase in wt% of beryl particles up to 6%. But toughness increased with an increase in wt% of beryl particles up to 10% and remained constant. The annealed samples showed a decrease in UTS (18.7%) and hardness (1.8%). The microstructural studies revealed uniform distribution of beryl particles in the composites, and XRD analysis revealed the chemical composition of the MMC and the presence of beryl in composite. Experimental studies reveal that there is an enhancement of UTS by 10.7%, hardness by 11.1% and the toughness from 2 to 5.75 J/m3. The % elongation has decreased from 11 to 6% when wt% of beryl was varied from 0 to 14%.
TL;DR: In this article, a quadrilateral plate bending finite element for the computation of natural frequencies of plates with arbitrary geometry is presented, which is based on the Reissner-Mindlin plate theory using assumed strains rather than displacements.
Abstract: This paper presents the development of a quadrilateral plate bending finite element for the computation of natural frequencies of plates with arbitrary geometry. This element is based on the Reissner–Mindlin plate theory using assumed strains rather than displacements and contains only the three physical degrees of freedom at each of the four corner nodes. Tests of convergence are first established for square plates with both simply supported and clamped on their edges where it is shown that a good rate of convergence is obtained using few elements. Other tests are then applied to rectangular, circular, skew and stepped plates, in addition to a rectangular plate with a central cutout as well. The numerical results obtained show that the present element has successfully passed patch tests and its results of the natural frequencies and the associated modes of vibration are in excellent agreement when compared with analytical and other available numerical solutions.
TL;DR: In this paper, the effect of Rayleigh number (Ra), Prandtl number (Pr) and heating frequency of the wall (ω) on heat transfer rate was investigated in a fluid-filled square cavity with sinusoidal heating from top surface.
Abstract: The prime objective of the present numerical study is to analyse buoyancy-driven thermal flow behaviour inside an enclosure with the application of nonlinear heating from top surface which is commonly essential in glass industries. A fluid-filled square cavity with sinusoidal heating from top surface, adiabatic bottom wall and constant temperature side walls is considered here. The thermal flow behaviour has been numerically observed with the help of relevant parameters like stream functions, isotherms and Nusselt number. For the present investigation, Rayleigh number (Ra), Prandtl number (Pr) and heating frequency of the wall (ω) are varied from 103 to 106, 0.7 to 7 and 0.5 to 2, respectively. It has been noticed from the investigation that flow dynamics drastically alter with Ra, ω and Pr. However, the effect of Ra on heat transfer rate has been found to be significantly higher while compared with the influences by ω and Pr.
TL;DR: A finite element formulation based on the first-order shear deformation theory is developed in the present study using nine noded isoparametric shallow shell elements as mentioned in this paper, which is validated by comparing the solutions obtained in terms of natural frequencies with the relevant published results and also experimental data.
Abstract: Cut-outs are the integral parts of laminated plate components in a variety of civil, aerospace and marine engineering applications. Cut-outs alter the dynamic behaviour of the structures by reducing mass and stiffness simultaneously. The glass epoxy laminates are fabricated by resin infusion method through vacuum bagging system in the laboratory. The experimental studies are carried out on composite plates with cut-out positioned at different locations in the laminate. A finite element formulation based on the first-order shear deformation theory is developed in the present study using nine noded isoparametric shallow shell elements. The effects of rotary inertial contribution of mass on the natural frequencies are studied in the present paper. The present finite element formulation is validated by comparing the solutions obtained in terms of natural frequencies with the relevant published results and also experimental data. The correlation between experimental and numerical mode shapes is established by using modal assurance criteria.
TL;DR: The evaluation and analysis of the existing facility layout in Jordan Light Vehicle Manufacturing Company is concerned with investigating the possibility for improvement to cope with increased demand and better utilization of available resources.
Abstract: The generation of layout alternatives is a critical step in the facilities planning process since the layout selected will serve to establish the physical relationships between activities. This paper is concerned with the evaluation and analysis of the existing facility layout in Jordan Light Vehicle Manufacturing Company and investigating the possibility for improvement to cope with increased demand and better utilization of available resources. Five alternatives were proposed using systematic layout planning for a possible arrangement of different facilities within the plant. The proposed alternatives were compared and ranked using the analytic hierarchy process based on the total traveling distance of materials between production facilities, total space usage, and activity relationships. The alternatives were ranked using three criteria, and the overall consistency was determined (6.918%, fair well below 10%). This case is implemented in a military institution in Jordan, and the used tools were not applied before.
TL;DR: In this article, an experimental and computational investigation has been performed to depict how the heat transfer and pressure drop attributes vary with different plenum shapes under different flow rates and heat inputs in microchannel heat sink (MCHS).
Abstract: Heat sinks, cooled by flowing fluid in the microchannels fabricated upon them, successfully proved effective cooling solution in electronic components. The entire thermal output of such a heat sink depends upon the characteristics of fluid flowing in the channels and the plenums placed subsequently at inlet and outlet positions. The flow phenomena got influenced by channel aspect ratio, plenum aspect ratio and flow arrangements in the plenums placed at inlet and outlet positions. In the present study, an experimental and computational investigation has been performed to depict how the heat transfer and pressure drop attributes vary with different plenum shapes under different flow rates and heat inputs in microchannel heat sink (MCHS). Test runs were performed by maintaining three constant heat inputs, 50 W, 100 W and 150 W in the range 221 ≤ Re ≤ 398.
TL;DR: Importance measure analysis indicates the drill string and rotary head are the most critical subsystems of machines A and B, respectively, and under the proposed maintenance policy, the reliability of the drilling systems of machines a and B is improved.
Abstract: Drilling, as the initial stage of exploitation in open-pit mining, has a significant effect on subsequent mining stages. Any failure in a drilling machine stops the drilling operation and, as a result, all following operational phases come to a halt. The drilling system is the most important part of the drilling operation. This study selected two new rotary-type drilling machines (A and B) in Sarcheshmeh Copper Mine in Iran as a case study to perform a reliability and availability analysis of their drilling systems. The drilling system was divided into three independent subsystems; drill string, rotary head, and mast. The reliability modeling used a reliability block diagram and Monte Carlo simulation. Reliability and availability were evaluated, and the importance of each subsystem estimated. A preventive maintenance schedule was proposed using weighed reliability allocation to achieve the reliability target. The results show the mast is the most reliable subsystem. Importance measure analysis indicates the drill string and rotary head are the most critical subsystems of machines A and B, respectively. Finally, under the proposed maintenance policy, the reliability of the drilling systems of machines A and B is improved.
TL;DR: In this article, a power load forecasting model based on a back-propagation neural network was designed and embedded in an ultrasonic power supply, referred to as the new ultrasonic Power Supply; the traditional ultrasonicPower Supply without power load forecast was referred as the traditional power supply; both these power supplies were used in an experimental process of 7085 aluminum alloy ultrasonic-assisted casting.
Abstract: The use of power load forecasting in aluminum alloy ultrasonic-assisted casting systems can improve its working efficiency and stability and simultaneously improve the casting quality of the aluminum alloy as well. A power load forecasting model based on a back-propagation neural network was designed and embedded in an ultrasonic power supply, referred to as the new ultrasonic power supply; the ultrasonic power supply without power load forecasting was referred to as the traditional ultrasonic power supply. Both these power supplies were used in an experimental process of 7085 aluminum alloy ultrasonic-assisted casting. The power load range and harmonic frequency range were 953.01–1194.02 W and 16.03–19.1 kHz for the traditional ultrasonic power supply with an average grain size of 179.93 µm and 1073.1–1213.02 W and 17.94–20.04 kHz for the new ultrasonic power supply with an average grain size of 139.41 µm, respectively. The results of the ultrasonic-assisted alloy casting experiment showed that the design of the proposed power load forecasting model could improve the work efficiency of the assisted casting system as well as the quality of the aluminum alloy casting.
TL;DR: In this paper, a total of 96 artificial neural network models have been created and trained on the basis of the total 700 data sets presented in Part I of the paper, while 692 data sets have been employed for formulating the ANN model using the ANN tool of MATLAB student version available at the college.
Abstract: Heat pipes are one of the heat transfer devices adopted in various applications due to its high heat transfer capability. Recently, heat pipes are charged with different nanofluids to increases its performance. Thermal performance of heat pipe charged with nanofluids depends of various factors related to operating conditions, working fluids, heat pipe, etc. Thus, extensive experimentation work is required to recommend appropriate parameters for different industrial applications. In such cases, in order to reduce experiments and to propose the appropriate combination of parameters, experimentation results need to be modeled using fundamentals of simulation. In the Part I of the paper, extensive experiments have been carried out on cylindrical heat pipe with silver nanofluid as working medium. In the present paper, total of 96 artificial neural network models have been created and trained on the basis of the total 700 data sets presented in Part I of the paper. Out of 700 data sets, eight data sets have been randomly separated for post-training simulation of the model, while 692 data sets have been employed for formulating the ANN model using the ANN tool of MATLAB student version available at the college. The models have been prepared to predict the thermal performance of cylindrical heat pipe under study when one, two and three parameters have been considered as output neurons one by one and six parameters as input neurons. Out of six input parameters, heat load, average evaporator and average condenser temperature are related to operating condition, size and concentration of silver nanoparticles are related to working fluid, and inclination angle is related to position of heat pipe. Trained 96 ANN models have been simulated using eight data sets, and the best ANN model has been proposed on the basis of minimum value of error in prediction in terms of MSE, NMSE, MAE, MARD and MRE. The best ANN model identified for one, two and three output neurons is single-layer feed-forward backpropagation network with six neurons of hidden layer, cascade feed-forward backpropagation network having three neurons at hidden layer and single-layer feed-forward backpropagation network with 12 neurons of hidden layer, respectively. It is also concluded that for single output neuron, any one type of error in prediction can be considered to select the best ANN model. But for more number of output neurons, comparison of various types of error in prediction is essential to judge the best ANN model.
TL;DR: A comparison has been made on the basis of two parameters, i.e. fitness function and regression, and MSPSO is found to perform better than the other two optimization algorithms, and their results are then compared.
Abstract: As the calculation of the exact position and orientation of the end effector of robot manipulator is mandatory to obtain inverse kinematics solution, an artificial neural network is used to obtain inverse kinematics as it reduces the computational time as well as complexity associated. The backpropagation algorithm that is generally used for updating weights and biases requires the sensitivity function of the system which is sometimes difficult to obtain. Here, training of neural network means optimizing the parameters of neural network, i.e. weights and biases, for which particle swarm optimization (PSO) is used. PSO is suitable for learning neural network as it does not require the derivative of an objective function. In this work, the parameters of neural networks, i.e. weights and biases, are optimized using three different optimization algorithms, i.e. PSO, segmented particle swarm optimization (SPSO) and modified segmented particle swarm optimization (MSPSO), and their results are then compared. Further, a comparison has been made on the basis of two parameters, i.e. fitness function and regression, and MSPSO is found to perform better than the other two optimization algorithms. Fitness function value obtained using MSPSO is 6.18e−09, using SPSO is 1.1e−05 and using PSO is 2.35e−03.
TL;DR: In this article, Alumina nanoparticles (Al2O3 NPs) were successfully prepared from aluminum nitrate precursor and methanol using the precipitation method, while NaOH was added after stirring.
Abstract: Alumina nanoparticles (Al2O3 NPs) were successfully prepared from aluminum nitrate precursor and methanol using the precipitation method, while NaOH was added after stirring. The prepared Al2O3 NPs were synthesized at the calcination temperature of 400 °C and 600 °C for 2 h. Later, the synthesized Al2O3 NPs were characterized by X-ray diffraction and scanning electron microscopy analysis. The conducted experiments show that the calcination temperature was found to have a strong influence on the Al2O3 NPs’ stability and processing time. It was clearly observed that with the increase in calcination temperature the crystallite size of the sample increases, indicating the enhanced crystallinity. The crystallite size of the synthesized Al2O3 NPs was in the range of 53–72 nm. The economic analysis of the produced Al2O3 NPs has indicated that the precipitation method is cost-effective.
TL;DR: In this paper, the effect of thermal barrier coated (TBC) on top of the piston used in CI engine was investigated when diesel and jatropha biodiesel (JB 100) were used as fuel.
Abstract: In this paper, the effect of the thermal barrier coated (TBC) on top of the piston used in CI engine was investigated when diesel and jatropha biodiesel (JB 100) were used as fuel. Two pistons were selected for TBC coating with a thickness of 50 μ as a bond coat and 250 μ as a topcoat. The first piston was coated with 7% YSZ (LHR 1) and second piston is coated with 2% Nd + YSZ (LHR 2) as a topcoat for the two pistons Ni–Cr–Al–Y used as a bond coat. Experiments were conducted to study the performance, emission and energy balance using standard piston and TBC-coated pistons. The results show that the BTE of an LHR 2 engine using JB 100 is 4.2% higher than the STD diesel engine. The BSFC of an LHR 2 engine using JB 100 fuel was reduced by 11.4% lower than the STD diesel engine. The HC and CO emissions were declined by 20% and 16% for the LHR 2 engine while comparing with the STD diesel engine and NOx emissions were increased by 15% in the LHR 2 engine with JB 100.
TL;DR: In this article, the damping force of the absorber is switched between the maximum and the minimum values according to certain control logics, and four different control strategies are considered.
Abstract: It is shown that a passive vibration absorber can completely quench the self-excited vibration only for certain parameter values, like the strength of instability in the primary system. The present paper numerically explores the performance of semi-active vibration absorber in controlling self-excited vibration. In the proposed semi-active scheme, the damping force of the absorber is switched between the maximum and the minimum values according to certain control logics. Four different control strategies are considered—these are on–off velocity-based ground-hook control (VBG), on–off displacement-based ground-hook control (DBG), continuous VBG and continuous DBG. Numerical simulations are performed in the MATLAB Simulink to explore the efficacy of the control strategies. It is shown that the on–off DBG control is superior to all other control strategies.
TL;DR: This paper aims to review the label-free microfluidic techniques for the detection and isolation of CTCs that have the potential to preserve phenotypic and genotypic characteristics of isolated cells.
Abstract: Circulating tumor cells (CTCs) are the tumor cells that get detached from a primary tumor site and enter bloodstream circulation that promotes the metastasis condition of cancer. The detection and analysis of CTCs hold significant clinical and research value in terms of cancer diagnosis, prognosis, treatment, and drug development research. Isolation and analysis of CTCs are already proven as a promising tool for effective drug screening. CTCs in the circulation can be considered as biomarkers for the early-stage detection of cancer. CTCs also offer the opportunity to study, monitor, and ultimately gain insights into the process of cancer metastasis. Among the existing approaches, microfluidic technology has become a hot spot in CTC detection and isolation due to their promising features such as automation, high precision, accuracy and sensitivity, portability, that are amenable to the development of point-of-care devices. CTCs can be isolated from the blood by labeling the cells with tumor-specific biomarkers, but the use of chemicals for labeling may interfere with the downstream assay. This paper aims to review the label-free microfluidic techniques for the detection and isolation of CTCs that have the potential to preserve phenotypic and genotypic characteristics of isolated cells. The principle of operation, methodology, application, advantages, and limitations of the different techniques are discussed. The performance of the different techniques is assessed based on several parameters such as capture efficiency, throughput, purity, sensitivity, and cell viability. Finally, a brief discussion on the challenges, commercialization aspects, and future perspectives is presented.
TL;DR: In this paper, high-temperature wear behavior of Al6061 substrate material with Ni-Al2O3 nanocomposite coating at different elevated temperatures is studied. And the results reveal that the dominant wear mechanism of the Ni−Al 2O3 coating was in abrasive nature at 40°C which turned into completely adhesive nature at elevated temperatures between 80 and 140°C.
Abstract: The lightweight materials like aluminium is used in most of the automobile, aeronautical applications due to its high strength to weight ratio. In the present study, high-temperature wear behaviour of Al6061 substrate material with Ni–Al2O3 nanocomposite coating at different elevated temperatures is studied. The tests were conducted at dry sliding wear conditions. The coating was carried out by electrodeposition process. In addition to high-temperature specific wear, hardness of the glaze layer and friction force of composite coating are investigated. The results reveal that the dominant wear mechanism of the Ni–Al2O3 coating was in abrasive nature at 40 °C which turned into completely adhesive nature at elevated temperatures between 80 and 140 °C. The minimum mild wear with reduced frictional force was noticed at 80 °C due to the formation of glaze layer. This anti-wear resistance glaze layer is formed by the sintering of debris and oxide particles at the interface of pin and disc. At 140 °C, severe wear with serious plastic deformation was observed. The improvement in the specific wear is attributed by the presence of nano-Al2O3 particles in the Ni matrix and wear resistant glaze layer. This was witnessed by the microstructure observations by SEM, EDS, and microhardness measurements.