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Various kinds of biomass fuels are used for boiler and other kinds of thermal applications. The presence of moisture, ash and calorific value are known to be the most significant quality factors which influence the effective performance of a biomass fuel for a plant. The reasons for measuring the above mentioned quality factors are to perform the economic analysis and to control the combustion. The relevant industries are interested to obtain a method for predicting these quality factors quickly and consistently; and also to identify biomass fuels containing optimal level of these factors. In the present work, five different biomass fuels have been considered such as rubber wood, eucalyptus wood, mixed wood (tamarind tree and neem tree woods), palm shell with fiber and juliflora woodchips. The moisture content in the considered woods have been found to be 27.74 wt.%, 37.78%, 30.19 wt.%, 23.26 wt.% and 37.01 wt.% respectively. The main objective of this work is to maximize the efficiency of production. Grey relational analysis has been carried out to optimize the moisture content, ash content and calorific value in order to achieve cost savings and fuel efficiency. Also, the economic analysis has been done with the operational costs. KEY WORDS: Biomass, Fuels, Energy, Boiler, Optimization Bull. Chem. Soc. Ethiop. 2023, 37(4), 1055-1064. DOI: https://dx.doi.org/10.4314/bcse.v37i4.20

In the present work, the minimization of total manufacturing cost of an assembly considering tolerance allocation using various optimization algorithms have been addressed. Complex assembly which consists of more than one critical dimension with any one dimension of the part involved in more than one dimensional chain has been considered in this work. The manufacturing cost of the various parts of an assembly with tolerance allocation has been minimized using the cost tolerance model. The benchmark solution to the problem has been derived using Lagrange Multiplier (LM) method. The results are improved using Genetic Algorithm (GA) and Artificial Bee Colony (ABC) algorithm by considering the Alternate Nominal Dimension Selection (ANDS). The results have been compared with LM method and found GA outperformed ABC algorithm. Further the research has been extended by considering ANDS and Alternate Process Selection (APS) using Teaching-Learning Based Optimization (TLBO) algorithm and the results have been compared with benchmark solutions. The proposed method is suitable for any type of complex assembly. An Improved Knuckle Joint (IKJ) assembly has been chosen for the illustration of proposed methodology with an implementation strategy. From the results, it was noted that TLBO yielded better results in the aspect of minimizing the total manufacturing cost of IKJ assemblies.

Manufacturing requires reliable models and methods for the prediction of output performance of machining processes as the demand for highly automated machine tools in the industry has been increased. The prediction of optimal machining conditions for good surface finish and dimensional accuracy plays a very important role in process planning. In the present work, dry turning of austenitic Stainless Steel (SS303) using CVD multi-layer (TiN/Al2O3/TiCN) coated carbide insert has been investigated. Cutting speed, feed rate, and depth of cut have been considered as the input process variables for the dry turning process. Taguchi's L9 orthogonal array has been utilized for designing the experiments. A Grey-Fuzzy logic approach has been employed to investigate the multi-objective optimization of turning process parametric combination to provide minimum Surface Roughness (SR) with the maximum Material Removal Rate (MRR). Analysis of Variance (ANOVA) technique has been employed to identify the most influencing input process variable for achieving minimum SR and maximum MRR. Morphology analysis has been performed on the machined surfaces and the chips generated during the machining processes using a Scanning Electron Microscope (SEM) in order to relate the surface quality with the input factor setting.

Supplemental material, sj-docx-1-pie-10.1177_09544089221150726 for Mechanical characterization and frictional wear behavior analysis on nano tungsten carbide and molybdenum disulfide particles reinforced aluminium 7075 composites by D Vignesh Kumar, S Arulselvan, A Arul Marcel Moshi, C Veera Ajay and P Balamurugan in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering

Supplemental material, sj-docx-2-pie-10.1177_09544089221150726 for Mechanical characterization and frictional wear behavior analysis on nano tungsten carbide and molybdenum disulfide particles reinforced aluminium 7075 composites by D Vignesh Kumar, S Arulselvan, A Arul Marcel Moshi, C Veera Ajay and P Balamurugan in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering

The experimental analysis carried out in this paper aimed at the selection of optimal machining conditions for the 3D profile machining of Inconel 825 alloy using Wire Electrical Discharge Machining (WEDM). It was noticed that the 3D profile machining of Inconel 825 alloy using WEDM process has not been performed and reported so far by the researchers in this domain to the best of our knowledge. As the machining of Inconel 825 alloy is difficult using the conventional machining processes, nontraditional machining is generally used. As the material is conductive, the WEDM process is suitable to machine this material. The effects of input factors such as wire material, pulse on-time, pulse off-time, peak current, wire tension and gap voltage on the material removal rate (MRR), surface roughness (SR) and dimensional shift (DS) have been investigated using [Formula: see text] mixed-level orthogonal array of experiments. The DS value for every machining condition has been predicted and inputted into the CNC system as the wire offset value to enhance the dimensional accuracy of the product. The parametric analysis has been done by Minitab software. Analysis of variance (ANOVA) has been used to find the significant parameters affecting surface quality. The regression equations have also been formulated to study the adequacy of the model. Multi-response optimization based on the Gray Relational Analysis has been employed and the results that optimize the MRR and SR simultaneously have been suggested. SEM images have been taken on the machined surfaces to compare the surface finish on the specimens.

The ultrasonic-assisted stir-casting technique improves the uniform dispersion of nano-reinforcements in aluminum hybrid metal matrix composites. In the present study, the process parameters of the ultrasonic-assisted stir-casting method, such as ultrasonic vibration time, and depth of ultrasonic vibration along with the speed of mechanical stirrer, are optimized on A356 hybrid composite material optimally reinforced with aluminum nitride, multiwalled carbon nanotubes, graphite particles, and aluminum metal powder using the desirability function approach. The process parameters are optimized against the response factors such as porosity, ultimate tensile strength, and wear rate of the composites. The optimum combination of input factors is identified as stirring speed (600 r/min), ultrasonic vibration time (2 min), and depth of ultrasonic vibration (40 mm) among the selected range. The corresponding output response values are found to be porosity (1.4%), ultimate tensile strength (247 MPa), and wear rate (0.0013 mm3/min). The ANOVA results have revealed that depth of ultrasonic vibration showed significant contribution among the input factors. An artificial neural network model is developed and validated for the given set of experimental data.

The process-parameter optimization of a wire electrical discharge machining (WEDM) process has been performed with an Inconel 825 alloy during taper profile machining. The input parameters have been considered at three different levels and the number of experiments to be performed was decided using Taguchi's Design of experiment (DOE). The output performances such as material removal rate (MRR), Surface roughness (SR) and taper error (TE) were considered simultaneously for the optimization process. The experimental results were analysed using Grey relational analysis (GRA) and the best experimental trial was identified based on ranking. The influence of the input parameters was analysed using the ANOVA technique. The regression equations to predict the output responses were formed using the experimental results and the correlation between the experimental and regression equation results.

The problem of water scarcity is increasing day by day due to various causes such as polluting the environment, urbanization, climate change due to the heavy usage of fossil fuels, less awareness in storing the water when it is available, etc. However, in seashore areas, the availability of fresh drinking water is very low. This demand motivated to suggest a low cost and renewable energy based desalination system to convert the brackish water into potable water. Solar still is a simple device which can convert the available waste or brackish water into fresh potable drinking water utilizing solar energy. The designed solar still was fabricated and tested under the normal atmospheric condition. Present work is to investigate the effect of kanchey marbles as energy storage material in the overall efficiency of solar stills. The performance of the solar still with kanchey marbles was 16.32% higher than the conventional still.

Natural fibers achieved significant attention in the structural area even though they have comparatively less strength than the regular materials. Because of having higher strength to weight ratio, natural fiber composite structures play a noteworthy role in several application domains. Natural fibers are hybridized in order to have the composite structures with the integrated strength of the individual fibers. In this work, two natural fibers such as tamarind seed powder and palm fiber have been identified and hybridized composite specimens have been fabricated in four different combinations by varying the volumetric ratio for testing their tensile strength, impact strength and hardness value. SEM images have been taken to carry out the morphology study on the surfaces of the prepared composite specimens. The obtained results confirmed the suitability of the proposed composite structure for the various existing structural applications.

In the present scenario, one of the major issues being faced in all the industrial as well as institutional organizations is energy conservation. Conserving energy is a significant phenomenon for preventing the environment and for reducing the energy expenditure met by the organizations. Even though enough awareness among the employees is made on energy conservation, the behavioural change cannot be achieved desirably along with their stressful regular works. Organizations are now focusing on going with renewable energy resources like wind energy and solar energy for balancing the additional energy consumption. Few modern organizations have introduced some critical drivers with the view of conserving the excess energy. Bricks incorporated with phase change materials are employed in large size industries in order to reduce the temperature fluctuations in turn reducing the energy consumption. As technology gets developed day by day, the need of energy is becoming increasing. Conservation of energy is so that playing a vital role in the current scenario of the entire world. In this comprehensive review work, various techniques so far suggested by the experts in this field are elaborated to preserve the energy consumption rate in buildings by means of various views.

Liquid penetrant test (LPT) is one of the easiest and effective crack detection methods used in industries as it can be used to check a wide range of materials except porous materials. It is based on the capillary rise principle and used to detect surface discontinuities. In the present work, the effect of vibration and temperature on the effectiveness of Liquid Penetrant test on plain low carbon steel A516 Grade 70 is presented, which would give us a clear insight about the role of temperature and vibration on the indications produced in LPT. It is observed that at higher vibration and higher temperature combination, the indication is the largest.

Natural fiber composites are playing the leading role in the recent research fields for their abundance of availability and comparable strength to weight ratio with the synthetic fiber composites. With this motivation, a low modulus fiber (bamboo fibers) hybridized with a high modulus fiber (Glass fibers) epoxy composites are taken for this work to evaluate their desirable mechanical properties. Usually strength of composite specimens is optimized by changing the ply orientation and volumetric ratio of fiber and matrix. But, in this analytics, a novel approach has been followed in which the hybrid composite laminates have been fabricated with five different lamina orders (B/B/B/B, B/G/B/B, G/B/G/B, G/B/G/G and G/G/G/G) using compression moulding machine. Various strength tests such as tensile, flexural and impact strength analyses have been performed. The strength values of the five specimens have been compared under the proposed loading conditions for choosing the better combination of hybrid composite structure exhibiting high strength. To validate the results, numerical analysis has also been made using ANSYS software.

The aim of this study is to examine and compare the effectiveness of entrepreneurship awareness camps conducted in the two academic years 2017–18 and 2018–19 at National Engineering College, Kovilpatti, Tamilnadu, India. Quantitative method through questionnaire survey has been followed for data collection in which questionnaires were distributed to respondents (camp participants) of 2017–18 and 2018–19 in various branch students of the institution. This study evaluates the effect of awareness camps about entrepreneurship on the response and behaviour of engineering graduates of the institution. Kirkpatrick’s program evaluation model showed that the entrepreneurship awareness camp significantly enhanced the entrepreneurial culture among the youth. However, this study is limited based on the feedback received from the participants of the camps conducted during August and September of 2018 and 2019. The results of the proposed study showed that the program created significant level of positive impact among the partakers.

Extensive research has been carried out to optimize the process parameters of several machining processes. Optimizing the influencing parameters of the turning operation is a precise action that determines the desired level of quality. This study focuses on the multi-criteria optimization of the CNC turning process parameters of stainless steel 303 (SS 303) material to achieve minimum surface roughness (Ra) with maximum material removal rate (MRR) by means of Taguchi-based grey relational analysis. A CNC machine was tested following Taguchi’s L9 orthogonal array design. Grey relational analysis was used as the multi-criteria optimization tool. The significance of each individual process parameter on the overall characteristics of the turned specimen was estimated using analysis of variance (ANOVA). Regression equations were generated using the input factors with the selected output parameters. In addition, a morphological study of the chips produced by the turning process was carried out using SEM images in order to relate the chip geometry with the output responses.

Fiber metal laminates (FML) are used in outer covering of the fuselage skin structure. The thrust force and the torque generated during drilling process affect the quality of the holes on the structure. The magnitude of cutting forces is controlled by optimizing the drilling process parameters. In this study, the influence of drilling parameters such as spindle speed, feed rate and the weight percentage of layered double hydroxides (LDH) in the binder epoxy on the thrust force and torque during drilling operation was studied. The experiments were designed based on Taguchi’s L9 orthogonal array. The Gray Relational Analysis was used as multi-objective optimization tool for finding the optimal combination of process parameters. The spindle speed was identified as the most influencing process parameter to affect the drill quality in the FMLs. SEM images taken on the drilled specimens for the best and worst input parameter settings were compared and discussed. The regression models were generated to predict the output response values within the range of actual experiments.

The foremost intention of this work is to test the suitability of the Ficus religiosa Root Fiber (FRRF) as the better reinforcement for the natural fiber-reinforced composite structures. In the current work, the attempts have been made with the view of improving the physical, thermal, chemical, surface, and crystalline properties of FRRF employing 5 wt% of NaOH solution. Five samples of FRRF have been prepared by soaking the raw fiber in the alkali solution under different soaking times. The thermogravimetric analysis results reveal that the alkali-treated FRRF soaked for 60 min holds a maximum range of thermal stability (improved by 9.54%); in turn, the remaining analyses have been carried out with that fiber samples. The increased quantity of cellulose contents was witnessed over the surface of treated FRRF. The improvement in the CI from 42.92–48.64% was noted as the result of X-Ray Diffraction test. The morphology study results ensured that the surface of the treated FRRF became so rough comparably, which confirms the removal of unwanted wax and impurities on the fiber surface. All the above observations validated that the proposed fiber is suitable to prepare the composite structures after the optimal alkali treatment.

Drone is an aircraft, which is specially designed without the aid of pilots. Drones are used in many areas such as surveillance, military and agricultural applications. The conventionally used drone aircrafts have been analyzed and some drawbacks have been found out in taking off as it requires long take off distance. This work aims to design an effective magnus wing rotor for a drone aircraft and to implement the same in the surveillance industry and in reconnaissance so as to make sure that the current indifference in applying the magnus wing rotor is eliminated by the effective functioning of the UMV Rotor. This refurbished design will increase the reliability of the magnus wing UMVs and it will equalize the commercial value with the other type of drone vehicles. The lift force generated by the fixed aircraft and the quadcopter is very less when compared to the magnus wing UMVs with the similar wingspan and fuselage geometry. The wingspan is greatly reduced by the magnus wing application and it can carry greater payload with tremendous lift force generation. The main objective of the proposed work is to redesign the rotor with the axially fixed spiral spokes which theoretically increases the vortex strength of the UMVs thereby increasing the lift of the cylinder as per the analytical calculation and the analysis of the particular drone design. The magnus wing rotor has a drawback as it suffers an abrupt lifting failure when there is any power cut off. The span discs attached at the ends will reduce the jeopardy by acting like a flywheel as a temporary energy storage mechanism and thereby giving an option for the application in the relevant industries.

Apart from moulding process, the plastics are required to be machined in many occasions so as to impart required dimensional accuracy. The turning operations of plastic materials pose challenges owing to its inherent problems in imparting required Surface Roughness (SR) and improved Material Removal Rate (MRR). High performance Acrylonitrile Butadiene Styrene (ABS) material has been chosen in the proposed work to study its machinability under turning operation. It is widely used in the home appliances, safety helmets and interiors of automotive because of their flexible structural characteristics. The various influencing factors like Spindle Speed (SS), Feed Rate (FR), and Depth of Cut (DOC) related with turning process are considered in L16 orthogonal array experimental plan in order to optimize them to achieve better values for SR and MRR. The samples of ABS have been turned using CNC machine by setting the input parameters at various levels and the corresponding output responses have been predicted. The MINITAB-18 software is employed to predict the optimal parameter setting with the results obtained from the Grey Relational Analysis (GRA). Further, Regression Analysis (RA) is employed using Design Expert Software to form the equation connecting input and output responses. The results of GRA suggested the best combination of process parameters with respect to SR and MRR.

Hybrid metal matrix composites are gaining more importance in recent years. In this current investigation, aluminium alloy (AA7075) composites have been prepared with nano tungsten carbide (WC) and molybdenum disulfide (MoS2) as reinforcements using stir casting method and investigated. The nano tungsten carbide particles were added into the matrix in the proportions 0%, 0.5%, 1%, 1.5% and 2%, and molybdenum disulfide was added in the constant proportion of 5 wt.% to the molten metal. The prepared Al-hybrid composite samples were tested for their hardness, compression and tensile strength. Microstructure examination has also been performed to understand the distribution pattern of nano tungsten carbide and molybdenum disulfide particles in the base matrix by scanning electron microscope. From the results, it was found that there was steady improvement in composite properties when compared with the base metal while adding WC and MoS2. Thus, the prepared AA7075/MoS2/WC composites were guaranteed for high strength, hardness and exceptional microstructure stability. Dry sliding wear behavior on AA7075/MoS2/WC composites was investigated with the aid of pin-on-disc apparatus. Grey Relational Analysis tool was employed to identify the optimal setting of process variables, which results in lower wear rate and COF. The significance of factors such as sliding distance, sliding velocity and load on the wear characteristics was investigated by means of ANOVA. ANOVA results unveiled that load was the majorly influencing factor in attaining optimal wear characteristics. The tested samples have been investigated using scanning electron microscopy and reported.

Renewable energy-based desalination (RED) technique is gaining more importance over the desalination techniques as it appeared to be a promising technique towards low-cost desalination for sustainable growth as the energy demand towards other developments is continuously increasing. This study aims to incorporate energy storage materials and wick materials in the inclined solar to improve the fresh water produced. In this work, the performance of inclined solar still using coconut coir disk and energy storage material is analyzed experimentally. Characterization results showed that the porosity, absorbency, capillary rise, and heat transfer coefficient of 1-year dried coconut coir disk were found as 73.25%, 2 s, 10 mm/h, and 37.21 W/m2K, respectively, which is higher as compared with that of other coconut coir disks. The experimental results on the performance showed that total distillate from novel inclined solar still with hybrid techniques (energy storage materials and wick materials) were recorded as 3645, 4080, 4570, and 4890 ml for 3 months, 6 months, 9 months, and 1 year, respectively. While the total distillate outputs of an inclined solar still with only wick materials were recorded as 2560, 2670, 2930, and 3390 ml for 3 months, 6 months, 9 months, and 1-year coconut coir disk wick materials. The novel hybrid techniques used in the inclined solar still with energy storage materials enhanced the yield from 82.25 to 144.5% than the conventional solar still, whereas the inclined solar still with only wick materials enhanced the yield from 28 to 69.5% than the conventional solar still.

Grewia damine is a flowering plant found in India and Sri Lanka. The fiber taken out from the stem bark of G. damine is found to be novel and selected for characterization study. The G. damine stem bark fiber (GDSF) has rich in cellulose contents (57.78 ± 3.56%). Its lower density (1.378 ± 0.036 g/cm3) makes it fit for use in lightweight applications. The weight percentage values of the chemical constituents confirm the use of GDSF for structural applications. Crystallinity index of GDSF was noted as 30.35%. The mechanical properties of GDSF were predicted as 375.6 ± 16.58 MPa tensile strength and 126.2 ± 11.93 GPa modulus of elasticity. The morphological and atomic force microscopy study results revealed that the fiber has rough surface even in its raw form. Hence it can be used to prepare composite specimens with better bonding strength between fiber and polymer. The thermal stability of GDSF was noted as 326 °C. Weibull distribution plots were drawn for validating the physical and tensile property values of GDSF.