Emerging Trends in Mechanical Engineering

In order to manufacture various products with well-suited quality by machining, appropriate choice of process parameters is of prime importance. Hence, the present work focuses on modeling and optimization during Nd:YAG laser microgrooving of K-60 alumina ceramic material with an objective to find the optimum process parameters settings for minimizing the upper width deviation. The experiments are performed as per Box–Behnken design of experiments (BBDOEs) with four process parameters (diode current, pulse frequency, scanning speed, and number of passes) for parametric optimization in order to control the technological response characteristic (upper width deviation) of the precision microgrooves on K-60 alumina. Analysis of variance (ANOVA), response surface methodology (RSM), and particle swarm optimization (PSO) are subsequently proposed for predictive modeling and process optimization. Result shows the optimal setting of machining variables in laser microgrooving of K-60 alumina ceramic at pulse frequency of 4.4 kHz, diode current of 17 amp, scan speed of 35 mm/s, number of passes as 12, with estimated groove upper width deviation of 0.02669 µm. The methodology described here is expected to be highly beneficial for manufacturing industries.

For improved engine performance, the valve-train components must concern the parameters durability, environmental norms, the shorter valve response time, and lightweight design solution. In the valve-train system for designers and manufacturers, the stress concentrations accumulated on the valve due to the partial contact, which further cause failures in the valve. The partial contact between the valve, insert, and guide becomes uneven because of the thermal distortion load of the valve insert and guide. This paper proposes a detailed engineering analysis using finite element method of an automotive engine valve-train system using lightweight titanium for intake and exhaust valve. The complete structural virtual simulation assessment, the 3D linear heat transfer, and stress–strain approach used to get thermo-mechanical loading effect on valve-train system. The simultaneous comparative evaluation of existing steel grade material with proposed titanium material as a tensile test results benchmark. In addition, to define the material life characteristic the fatigue factor of safety evaluated by using Soderberg stress-life cycle in terms of both materials. Thus, the titanium alloy has enough potential as an optimal better material and high strength-to-weight ratio for the improved engine performance in compared to steel alloy.

Of many types of IC Engines, two types, namely diesel and petrol engines, are well established. Each one of them has certain limitations. The full load power characteristics of petrol engine are very good, but the degree of air utilization is also high. Diesel engines have part load characteristics but have poor air utilization. Comparatively, the emission characteristics for the diesel and petrol engines are poor due to the high peak temperatures. In the actual operation, basing on the stoichiometric fuel–air mixture ignition the fuel efficiencies are very much lowered in both the engines. From the observation, we see that the engine runs at part load and max power conditions. Therefore, an engine is to be developed, which can combine the advantages of diesel and petrol engine and also avoid the many of their disadvantages. In that course of action stratified charge engine is one, which is midway of the heterogeneous CI engine and homogeneous SI engine. Here an overview of stratified charge engine working and its combustion by fuel injection with positive ignition method is presented.

In modern electronic equipment, the use of heat pipes is steadily increasing as they have maximum heat transport capability per unit area. The driving mechanism in heat pipe is the capillary forces developed in fine porous wick to circulate the fluid. The heat transfer in heat pipe is by both condensation and evaporation. Loop heat pipe is one such kind, which has two-phase heat transfer. In this device, the working fluid is circulated due to surface tension forces formed in wick. It can be operated against gravity and can possess flexible transport lines. In the present work, the performance of loop heat pipe is investigated using different working fluids and wick materials. The results are obtained for low heat input ranging from 5 to 12 W. Results show that acetone fluid had better thermal performance when compared to other fluids as it has very low thermal resistance, which is almost half of the thermal resistance of water. As the heat load increased, the temperature difference also increased between the evaporator and condenser. A better thermal performance was obtained with nickel as wick material.

The objective of this work is to check the structural performance of the piston, while changing some of its design parameters. This paper describes the modelling and analysis of piston, which has been done using Solid Edge and Ansys 16.0. Analysis was performed on the piston with different head thicknesses (TH) and top land widths (b1) to observe its structural performance. The comparison has been done by using different materials (Grey Cast Iron FG 200, Aluminium 4032 and AISI 1020 Steel) for the same geometry to observe the consequences. The deformation in the piston has increased slightly when we decreased the piston head thickness and top land width. Thorough observation has been done with respect to equivalent stresses and we found that AISI 1020 Steel is a better material for the piston among the three materials considered but the stresses are lowest in Aluminium 4032. For piston of 12 mm head thickness and top land width, the equivalent stresses and deformation are found to be maximum for all the three materials used and are minimum when the piston head thickness and top land width are 19 mm.

The magnitude of waste disposal in public areas is increasing due to increase in population, change in the lifestyle of the human beings, and improper measures for reducing and recycling of waste. There is an urgent need for creating awareness among the public and spread motivation among the youth of the country. The problem can be overcome by segregation at source. The main motto of the project work is to develop a smart waste segregator to collect recyclable and reusable waste. It tries to reduce human interference by automating the system to the maximum extent possible. The model is developed and fabricated to meet the requirements for separating different kinds of wastes using various mechanisms and electronic circuits which include conveyor, Arduino board, sensors, motors, etc. It involves various mechanical operations for setting up the system and programming to make the electronic circuits work. The model can segregate wet waste, dry waste, and metal waste. The mechanical part of the system involves preparing conveyor frame and mechanisms for material transfer, whereas the electronic circuits include programming the movement of various mechanical elements to perform their jobs automatically. Waste alignment will happen with the help of resistance plates provided at both ends of the conveyor belt. Sensors with specific applications are used to identify wet, dry, and metal wastes. Bins are monitored using sensors to avoid overflowing of waste.

In friction stir welding process, developed heat is considered as an important factor because it strongly influences the properties of welding. In this study, the effect of heat index on tensile properties and forming behaviour of friction stir welded joints were studied. The influence of grain size on the hardness is also studied. Microhardness and grain size relationship of the welded blanks is expressed in the Hall–Petch equation. It was observed that the mechanical properties and hardness were better at lower rotational speed. An improved formability is achieved at the lower tool rotational speed rather than the high rotational speeds due to refinement of grains occurred at lower heat input.

The paper emphasizes the numerical investigation to analyse the three modes of conjugate convective heat transfer characteristics from seven non-identical heat sources (Aluminium) mounted on a substrate board (Bakelite). The objective is to determine the best mode of heat transfer which suits for cooling of ICs (heat sources), also temperature is non-dimensionalized as (θ), and it is predicted by applying fuzzy logic control. To accomplish this, numerical simulations are carried out using ANSYS Icepak to estimate the temperature distribution of the IC chips. Results suggest that the mixed convection is the better mode of heat transfer and the temperature of heat sources is reduced. Temperature of the heat sources is a strong function of their size and position on the substrate board. There is a strong agreement between the numerical values of ANSYS Icepak and predicted values obtained from fuzzy logic.

These days, NFCs are accentuating the greatest potential for engineers in numerous applications. A natural fiber polymer composite (NFC) offers the designer to acquire the fundamental properties in a munificent degree by the choice of fibers and matrix. Tapsi fiber reinforced polyester composites were made up with a statute of blends. The tensile, flexural, and impact properties of Tapsi fiber reinforced polyester composites were studied. The mechanical properties such as tensile strength, flexural strength, and impact strength of the Tapsi fiber reinforced polyester composites were assessed according to the ASTM guidelines. The impacts of alkali treatment (NaOH) of the fibers on these properties were likewise studied. It was observed that the mechanical properties of the polyester composite improved with increment in the fiber content. These properties were observed to be far and away superior when alkali-treated tapsi fibers were utilized as a part of the composites.

In consideration of total hip replacement (THR) and theoretical life estimation, we extensively performed finite element analysis and predicted the wear behaviour of different head sizes of 28, 30 and 32 mm and two bearing systems namely ZTA head—ZTA liner and Ti6Al4V head—UHMWPE liner. Static but stance activity was encountered for the 100 kg subject, where the ZTA head—ZTA liner combination exhibit less von mises stress compared to Ti6Al4V head—UHMWPE liner bearing. Interestingly, 30 mm femoral head experiences more jump distance (JD) and more range of motion (ROM) in comparison of the 28 mm femoral head, and less deformation compares to 32 mm femoral head. The wear behaviour is estimated using Archard’s law and predicted wear depth is around 600 µm for 15 years for 30 mm femoral head during articulating motion with identical tribocouple.

Enhancement of heat transfer rate in automobiles is one of the key research areas currently. To address one such heat transfer issue, the authors have attempted a detailed study about mixed convection heat transfer for a fluid in a lid driven square cavity with different blockages placed at the center of cavity and are maintained at constant wall temperature at a steady state condition. The fluid flow is due to the top wall which is in motion while the other walls are kept stationary. The governing differential equations are solved for a range of dimensionless constants like Reynolds number from 1 to 1000, Prandtl number from 1 to 100 and Grashof’s number from 0 to 105. It is observed that the heat transfer is more in triangular blockage when compared to that of square and cylindrical blockages. Also, in case of blockages with grooves, more heat transfer is observed in triangular blockage than square and cylindrical ones with grooves. Out of all cases studied in the current work, heat transfer rate is found to be better in triangular blockage with grooves.

Manufacturing simulation has a greater role to play in this era of smart manufacturing. Global competency can be achieved when industries are able to execute planned strategies at an operational level. Over the years simulation has been extensively used at strategic levels, where decisions concerning productivity, design, process reengineering, alternative model selection to be made, have long term effects. Many research experts have pointed at the need to use simulation at an operational level in manufacturing system. This paper explains the significance of simulation at an operational level. In order to analyze the above said research problem, a tin container production line in LVT containers plant unit at Hubballi, Karnataka, India was considered for the study. The main objective in this study is to maximize production rate through minimizing serious bottlenecks identified at various stages by proposing several scenarios without altering existing facility.

Work study is one of the important productivity improvement tools in industrial engineering methods and practices, through which productivity of man and machine can be improved. Work study has two main approaches, one is method study and other being time and motion study. This paper focuses on improving the productivity by minimizing the time and cost in an assembly section of an organization with the help of both manual and video work study techniques. Results of both the methods are initially analyzed and compared at the end. The existing method followed to assemble the actuators was recorded, and improved method was proposed using industrial engineering methods and practices which consumed less time and also unnecessary movements are eliminated. By adapting the proposed method, productivity improvement of 41.66% is being observed, and the time saved for assembling actuator was found to be 4 min per actuator. Video work study is found to be more accurate than conventional manual work study.

Proposing a suitable material for wind turbine blade is discussed in this paper. Low weight, high stiffness, high strength, and long durability are some of the salient features a material should possess to act as the wind turbine blade. Carbon fiber, glass fiber, and aramid fiber are used as blade materials in these days because they meet most of these features. In addition to, fly ash as filler material with polyamide fiber is discussed in this paper. The specimens were prepared by hand layup process. Erosion test is performed in air-jet erosion tester. The graphs are drawn according to smaller the better criteria of Taguchi L25 orthogonal array of two factors and five variables. Graphs obtained from dynamic mechanical analyzer for tensile test and three-point bending test are compared for different specimens. Hardness values are calculated by Rockwell hardness tester, and densities are calculated to analyze the void content.

The investigation on the fractured surface of steel wires in the tensile test and torsion test has been carried out using stereomicroscopic technique. The analysis has been done on cold drawn wires subjected to different pass schedules. Investigation revealed that pass schedule having optimum true strain resulted in the best mechanical properties. Hot rolled piano wire rod having carbon percentage 0.87% has been used in the investigation. The fully pearlitic microstructure is developed during lead patenting process of wire rod at 950 ℃. The wire rod has been reduced from 7.00 mm diameter to 2.6 mm wire diameter by subjecting it to three different pass schedules. The investigation revealed that highest UTS and TS properties are achieved in pass schedule-1 and pass schedule-2 respectively in the cold drawn wire of diameter 2.60 mm. The high reduction rate per die in pass schedule-1 has a negative effect on torsion strength whereas the low reduction rate per die in pass schedule-3 has negative effect on torsion strength as well as tensile strength.

This paper presents the comparison of characterization and investigation on viscosity, thermal conductivity and friction coefficient of Silicon carbide (Sic), Silicon nitride (Si3N4) and Magnesium oxide (MgO) nanolubricants for refrigeration applications. The characterization of nanoparticles was done by SEM, XRD and EDS tests. Nanopolyolester oil samples were prepared by two-step method for different volume concentrations of 0.15, 0.3, 0.45 and 0.6%. Viscosity of the nanolubricants was measured for different volume concentration and at various temperatures. The experimental results found that the viscosity and thermal conductivity of the Si3N4 nanolubricant is higher than the other nanolubricants. Also it is found that the coefficient of friction of Si3N4 nano lubricant is lower than the other nanolubricants. The viscosity of the Si3N4 nanolubricant has been enhanced by 41.6, 33.9, 31.2, and 37.1% at 0.6% volume concentration for 20, 30, 40, and 50 °C with respect to polyolester (POE) oil. The result displayed that the thermal conductivity of Si3N4 nanolubricant was enhanced by 42.4, 46, 45.6, & 41.4% corresponding to 0.15, 0.3, 0.45 and 0.6% volume concentration with respect to pure POE oil. This paper also emphasis on the comparison of tribological behavior of the nanolubricant and pure POE oil. It is found that the coefficient of friction was reduced by 1.3 times lower at optimal concentration of 0.6%. These conclusions suggest that Si3N4 nanoparticle as additives in the base POE oil can improve the lubrication and thermal properties of base lubricant and can be used for the refrigeration application.

The present work focuses on modeling and optimization during Nd:YAG laser microgrooving of Ti6Al4V titanium alloy material with an objective to find the optimum process parameters settings for the groove upper width as well as depth and heat-affected zone. The experiments are performed as per Box–Behnken design of experiments (BBDOEs) with four process parameters (diode current, pulse frequency, scanning speed, and number of passes) for parametric optimization in order to control the technological response characteristics of the precision microgrooves on Ti6Al4V titanium alloy. Analysis of variance (ANOVA), response surface methodology (RSM) and particle swarm optimization (PSO) are subsequently proposed for predictive modeling and process optimization. The methodology described here is expected to be highly beneficial for manufacturing industries.

Optimization of process parameters is an important technique in machining sector. In the present work, an experimental study has been performed in turning of AISI D2 steel using coated carbide tool in dry and forced air-cooled environment. Taguchi’s orthogonal array L9 has been used for running the experiments considering cutting speed, feed rate and depth of cut as process parameters and surface roughness, flank wear and cutting force as performance parameters. To optimize the performance parameters together in a single setting, an overall evaluation criterion (OEC) has been used. Analysis of variance (ANOVA) and average performance value of OEC is also analyzed. It is found that from the predicted setting of the average performance value of OEC, the surface roughness, flank wear and cutting force is reduced in both dry turning (DT) and forced air-cooled turning (ACT) as compared to the optimum value obtained from the experimental run.

Most layouts are designed for the initial conditions of the business; however, as the company grows it has to adapt to internal and external changes; a redesign is necessary for plant layout. There should be a relationship between output, shop floor area and manufacturing process. This study is based on the analysis of the current layout of the butterfly valve in WEIR BDK Valves, Hubballi. The current layout measurement is noted in the initial stage with the current layout and proposed layout drawings with the help of CAD software, and the time study, arrangement of machines, productivity and material flow of current layout are analyzed. The aim of this project is to purpose a new and efficient layout to reduce travel time, to minimize material flow and to find out the most efficient arrangement of machines in the assembly unit of butterfly valve section. The new proposed layout is analyzed using the ARENA simulation software, and the same is implemented in the company. After implementing, the time study, material flow and arrangement of machines of proposed layout are analyzed. This study also illustrates how simulation technique helps in solving the problems in plant layouts. It also helps to modify the plant layout to improve the productivity and overall efficiency of company. The efficient redesign of plant layout is necessary for operations and management costs.

This study presents a comparative analysis of different optimum annular fin arrays, which involve fins of constant thickness, nonlinearly varying thickness, and step change in thickness. The designs of the fin arrays are formulated as multi-objective optimization problems aiming at maximizing the heat dissipation rate and surface efficiency while minimizing the total fin volume. Computing the heat dissipation rate through the hybrid spline difference method (HSDM), the multi-objective optimizer NSGA-II is utilized for optimizing the considered three-objective functions in various combinations. Finally, to facilitate one in selecting a compromise fin array configuration out of multiple trade-off alternatives, a comparative analysis is performed among the trade-off solutions obtained for the considered three types of fin arrays.

Buy online pickup in store (BOPS) is one of the omnichannel fulfillment strategies which is gaining lots of popularity among omnichannel stakeholders. For this purpose, few large retailers have adopted BOPS strategy while many more are in queue to adopt for BOPS’s benefits to expand their business. To attract the customer to use BOPS environment, retailers often offer various discounts on products and services. In this paper, a novel discount strategy is proposed under BOPS environment to benefit both consumers and retailers. In this mechanism, the customer would be delighted through different discount categories which are based on travel distance to pick their order. To get depth insight into this strategy, a numerical illustration is enumerated. This strategy would be useful to the new market entrant in this area for expanding their business through leveraging such BOPS schemes.

These days the interest of people has shifted toward using natural fibers as reinforcement in the preparation of polymer composite material. Having superior properties such as lower density, higher stiffness, better mechanical properties and since the natural fibers are abundantly available, being renewable and biodegradable, the natural fiber-based composite preparation has become a wide area for research activity. This paper deals with the testing and analysis of the single edge notch bend specimen for the estimation of fracture toughness of the material. Six SENB hybrid composite specimens made of glass fibers, jute fibers and epoxy are prepared as per ASTM D-5045. Then, the models of hybrid composite are created in ANSYS to find J-integral and stress intensity factor. The purpose is to retain sufficient mechanical properties by adding layers of glass fiber, at the same time ensuring a lower cost and lower weight by reinforcing intermediate layers of jute fiber in it. Determining the mechanical characteristics of hybrid composite laminate was carried out by three-point bending test so as to compare it with ASTM D-5045 test method’s manual. Wherein, the results of the test specimens have satisfied the necessary conditions put forth by the test manual. Mechanical characteristics obtained with hybrid jute reinforced glass laminates enable the substitution of glass fiber by other natural fibers for moderately loaded applications to combine performance and economy.

The present study assessed the effect of control parameter, i.e. approach angle (A), cutting speed (B), depth of cut (C) and feed (D) on the response characteristics, i.e. material removal rate (MRR) and surface roughness (SR) during machining of titanium alloy using Taguchi technique. Experimental trials were performed on the lathe machine using the L9 orthogonal array. Statistical analysis carried out to know the contribution and effect of cutting parameters on response characteristics. From the analysis, it was found that the feed (D) was the most influential factor followed by approach angle (A) which affects the surface roughness (SR) while cutting speed (B) had a most significant effect on the material removal rate (MRR). Subsequently, an optimal control parameter was obtained and modelled for response characteristics.

In today’s rapid production scenario, scheduling plays a dynamic role in planning. In this work, open shop scheduling problem related to a copper flexible braids manufacturing company is considered. In a scheduling problem, the purpose is to find the orders of jobs on specific machines with an objective to optimize the makespan. Scheduling can be either manual or automatic. Manual scheduling of operations is a difficult task. Hence, computational methods are used to automate and simplify the process. In this work, integer programming and constraint programming-based mathematical models are developed to tackle this problem. The branch-and-bound (B&B) algorithm is applied for integer programming model, and branch-and-cut (B&C) algorithm is applied for constraint programming model in order to get optimized makespan. A comparison of results obtained from both mathematical models is done for selection of optimized makespan and identification of model.

Due to the government pressure and public awareness, industries are bound to incorporate sustainability in their manufacturing process. In this context, the concept of lean manufacturing and value stream mapping (VSM) process has been used widely in various manufacturing industries to minimize the waste in their production process. The objective of this study is to propose a conceptual model for the integration of VSM tool integrated with various sustainability indicators. The proposed model is capable to assess the manufacturing process into three sustainability dimensions such as economic, social, and environmental. This methodology was applied to two different manufacturing industries such as automotive component manufacturing organization and PVC pipe manufacturing organization, situated in India. The result demonstrated that the proposed methodology identified the areas of improvement after applying these integrated methodologies and clearly enabled the opportunities for improvements in both manufacturing organizations.

In recent days, the requirement of advanced materials plays an important role in the engineering field. Simultaneously, material properties have been fulfilled the demand for industrial applications. Advanced new materials are to be achieved through one or more materials combined with each other. Composite materials have been satisfied all kinds of applications. Due to their excellent properties, they are used in various fields such as aerospace, automobile, medical, communication, electrical and electronics fields. Titanium–graphite metal matrix provides excellent properties such as strength, hardness, corrosion resistance, thermal and electrical conductivities. Titanium–graphite composite samples with the volume fraction of graphite in the mixture are 3, 5 and 10% prepared by spark plasma sintering (SPS) process. It has been observed that addition of graphite into titanium provides higher amount of density and hardness. Metal matrix characterization has been studied through scanning electron microscope (SEM) and X-ray diffraction (XRD). Titanium–graphite composite has been machined by electrical discharge machining (EDM) process.

In the present work, the condition of machines and structures are determined by the condition monitoring technique of rotating machineries through vibration analysis. Here, the amplitude and frequencies of vibrating machines play a key role in the judgement of predicting the condition of the machineries. Henceforth, we have selected critical equipment for the testing which includes mill stands of bar rod mill (BRM-2) from the steel manufacturing industry. Now the amplitude of the equipment was taken by using vibrometer at different parts of the equipment, then by the FFT analyzer, the comparison was made between the parameters like amplitude versus time and amplitude versus frequencies. At the end with the help of the plots obtained the critical part of the equipment which was responsible for vibration was identified. Finally, with the remedial methods, the vibration was reduced to the acceptable level.

This research paper describes the multi-objective optimization of process parameters of photochemical machining process. Aluminium was selected as workpiece for obtaining maximum rate of material removal, minimum surface roughness and minimum edge deviation of predefined pattern. The selected machining parameters were etching concentration, etching temperature and etching time. To determine optimal solution, grey relational analysis was performed. To determine the most significant input parameter, analysis of variance of grey relational grade was carried out. The optimal condition of input parameters was found to be 400 g/L of concentration, 60 °C of temperature and 8 min of etching time. Etching temperature was found to be the most dominant parameter on the output response followed by etching time, while concentration being the least significant. ANOVA of grey relational grade showed the etching temperature was the only significant factor for machining of aluminium workpiece.

In recent years, the auto industry has been widely using the aluminum alloy in lightweight vehicles. Aluminum-alloying components like pistons, cylinder heads, brake rotor, carburetors, transmission housings, and wheels are used. Most of the work in automobile sector is on reduction of weight, especially in case of braking system. Brake rotors, which are available, are in heavyweight. Al6061 alloy has many applications in the transportation sector. Excellent mechanical properties can be achieved for Al6061 in addition to good ceramics like SiC and TiB2 as a reinforcement, due to which the alloy finds a wide range of applications (or many applications). Al6061 + SiC and Al6061 + TiB2 are the two particulate metal matrix composites, which are fabricated with different weight proportions (3, 5, and 7%) by in situ stir casting technique. With addition of ceramics (or the ceramics mentioned above), the alloy properties are highly improved. In contrast to the microstructure, mechanical and wear behavior on these two AMMCs will give the best material for manufacturing of a brake rotor.

Nickel–titanium (NiTi) shape-memory alloys (SMA) are being extensively used in high-end and crucial applications in the fields like aerospace, bioengineering, robotics, and automobile, and the areas of their application are growing at a high rate due to their unique characteristics. For all such applications, the machining of NiTi SMA is a crucial task. In this study, the machining of NiTi SMA using wire electrodischarge machining (WEDM) and copper wire as the electrode has been studied for the various input parameters. The quality and the time duration for the machining depend on the selection of input parameters such as pulse on/off time, wire feed rate and servo voltage. The experiments for the study were planned according to the full factorial design (FFD), and then, it was analyzed by response surface methodology (RSM) mathematical models. It was found that with the increase in pulse on and pulse off duration, the material removal rate increased accordingly. In the present experimental studies, for the higher wire feed rate, the MRR increased initially and then decreased thereafter.

The surface quality of the manufactured parts is an important factor affecting the functional properties such as corrosion resistance and fatigue strength of the part. For this reason, this study aims to develop surface roughness of Al 7075-T6 material which is generally used in the aviation and aerospace industry. In order to enhance the surface quality of the parts, the ball burnishing apparatus was designed and experiments were carried out at different parameters (force, feed rate, and medium). The design of the experiments was carried out using the Taguchi method, and the L9 orthogonal array was chosen. Also, the contributions of the parameters on surface roughness have been calculated with an analysis of variance (ANOVA). Consequently, the optimum surface roughness value was reached with parameters of the force 200 N, mineral oil, and feed rate of 0.1 mm/min. The most important parameters affecting the surface quality are found to be the burnishing force, feed rate, and medium, respectively.

Additive manufacturing is initially developed to meet the needs in the field of aerospace engineering. As the cost of sending a component into the space to replace the failed part is more than the actual cost of the product the researchers started working on printing machines. This effort of the researchers and research organization bought a 3D printing machine into the picture. Taking the 3D model as reference, the 3D printing machine prints the component by adding the material in layers. Later, the application of 3D printing was extended in many fields like medicine, automobile, and textile industry. Taking a step forward, a private research organization in Cambridge, Massachusetts institute of technology (MIT), has developed a 4D printing machine in 2013. 4D printing is printing a 3D component with smart material to add a fourth dimension called intelligence. Hence, this gave rise to programmable printing. This paper deals with 4D printing technology, materials suitable for printing the component, materials that add strength to the component, applications, challenges, and future scope.

FSW process are widely used in various automobile and aerospace industries nowadays, which encouraged us to take up this work for doing research. This paper reports the experimental investigations on the effects of process parameters, i.e., tool rotational speed, weld speed and tilt angle on the responses, i.e., tensile strength, impact strength, and elongation in dissimilar welding of Aluminum alloys of different grades using the solid-state welding technique Friction Stir Welding process. In view of the costlier process, Taguchi L9 is used for carrying out the research. As it is a complex process, to identify the significant variables, initial trial experiments are done on the same parent materials. Based on them, ranges are also found out for each input process parameter. A total of three input process parameters (tool rotational speed, weld speed, and tilt angle) are chosen for study and the output responses measured are tensile strength, impact strength, and elongation. ASTM standards are used in preparing the work pieces. After measuring its output responses, main effects are studied between the input process parameters versus output responses. This analysis can be further used in predicting the empirical equations with which the process can be automated based on the optimal values and microstructural investigations done.

The estimation of contact forces in elastic bodies leads to an inverse problem, and its solution procedure is different as compared to a direct problem. This paper discusses how a direct problem becomes an inverse problem and how these problems depend on boundary conditions of the elastic bodies. A cantilever beam for different boundary conditions is also investigated in the framework of finite element method. The numerical results show how a problem becomes direct or inverse for different boundary conditions. They also indicate the extreme sensitivity of forces to the input data for both direct and inverse problems.

The railway transportation system plays a very important role in society. In railway engineering, structural stresses, thermal stresses, contact stresses, surface cracks, plastic deformation and wear of the railway wheel have a serious issue, and also increasing speed and axle loads of the wheel reduces strength and creates wear. Thermal stresses are generated usually while breaking the operation of the vehicle. Present study deals with S-shaped wheel profile analysed by using finite element method and considered factors are displacement, stress distribution, temperature and deformation. The Hypermesh software is used for simulation; the maximum displacement obtained from simulation is 0.66 mm. The maximum stress obtained from simulation is 314 MPa. The maximum grid temperature obtained from simulation is 545 K. The result of FEA shows good agreements with real-life problems related to railway wheel.

In the present work, the performance of four-stroke variable compression ratio diesel engine is evaluated using soybean-based biodiesel. Blends of biodiesel are prepared by varying percentage of biodiesel in diesel (B20, B40, B60). Engine input parameters such as compression ratio (13:1, 15:1, 17:1) and load (4, 8, 1.2 kg) are varied to optimize the results. Taguchi method of optimization is used to study the effect of various combinations of input parameters on performance of VCR engine. Analysis of variance (ANOVA) is done to identify significance of individual input parameter on brake power, brake-specific fuel consumption, and exhaust emission. The optimization helps to select optimum values of compression ratio and load that would minimize exhaust emission and brake-specific fuel consumption but also maximize brake power. Engine performance is highly influenced by load.

The present work explains about the vibration response of a viscoelastic sandwich beam with functionally graded material constraining layers. These layers are formed by varying the ceramic (Al2O3) and stainless steel (SUS304) composition along the thinness direction. The basic kinematics is considered from Timoshenko beam theory due to inertia effect. The sandwich beam is formulated. Three-layered sandwich beam is modelled using the finite element method. The top and bottom layers are FGM layers and the middle layer as a viscoelastic core. The linear displacement field is assumed to model the FGM layers and also the core layer displacement field as non-linear. Hamilton’s principle is used to derive the governing equation of motion of the viscoelastic sandwich beam. The vibration analysis has been carried out by using the derived governing equation of motion with cantilever and fixed–fixed boundary conditions. The obtained results are compared with the available literature results. The natural frequencies are calculated with different boundary conditions by varying the core thickness. The influence of core thickness and FGM constraining layer index value on natural frequencies are observed.

Nanofluids play a prominent role in heat transfer applications. The thermophysical phenomenon is additionally necessary for these fluids. Many researchers’ have been measured these fluids, in terms of preparation, stability and thermal properties. Most of the industries measure mistreatment of different types of heat exchangers. In order to interchange this drawback, we tend to square measure mistreatments completely for different coolants like water with ethylene glycol, nanofluid, and hybrid nanofluid. These fluids have high thermophysical properties. The design and modeling of a double pipe heat exchanger is finished by creo 2.0 and temperature distribution, heat transfer constant is simulated by ANSYS Fluent.

It is known that the CI engine combustion process is complex phenomenon. The rapid progress has been made in multidimensional modeling of in-cylinder processes by suitable combination of assumptions and equations that can analyze the critical features. The CFD models gives us the complete understanding of the in-cylinder processes, reduce the cost of the expensive and time consuming experimental techniques. FLUENT is one of the versatile tools which is used for modeling of in-cylinder flows as well as exhaust pollutants. FLUENT has a set of assumptions and restriction. One such restriction is that the effect of Scalar Dissipation Rate Fluctuations (SDRF) is ignored. In the present paper an attempt has been made for the inclusion of SDRF by writing the User Defined Function and appending the same to the existing code FLUENT. Three swirl ratios 2, 3 and 4 with spherical bowl have been chosen and runs are made for these swirl ratios with and without SDRF. The simulated results are compared with the experimental results for validation.

The present work discusses the computation of the trajectory of a projectile with flat-fire trajectory approximation. The test case corresponds to 7.82-mm bullet of assault rifle AK-47. Initially, computational fluid dynamics (CFD) simulations are performed over the bullet with commercial CFD software, ANSYS Fluent. Density-based solver is employed to solve coupled continuity, momentum, and energy equations for Mach number of 2. The corresponding velocity of bullet is 680 m/s. The effect of turbulence on flowfield is accounted by using k-ε turbulence model. Flow features over the bullet and associated surface pressure distribution obtained from the simulations are explained. Predicted drag coefficient of bullet is validated against available experimental data, and the deviation is below 5%. Flat-firing approximation is used for simulating the trajectory of the bullet for which drag coefficient is an input parameter. Initially, the flat-fire trajectory code is validated against published trajectory data. The error between the predicted velocity and published data is below 0.05%. Next, flat-fire trajectory simulation is performed for bullet. Velocity, range, and height of the bullet are predicted as a function of time. It is found that the bullet travels a distance of 280 m before hitting the ground. During the course of travel, there is 33% reduction in its velocity and corresponding flight time is 0.63 s. The effect of variation in density with respect to altitude on range of bullet is also investigated. Range of the bullet at 4 km altitude is 16% higher than that of sea level.

Motivated by research gap, an annular fin of plane profile is investigated here as a multi-objective optimization problem primarily considering the maximization of the heat dissipation rate and, at the same time, minimization of the maximum induced thermal stress. The minimization of the fin volume and maximization of fin efficiency and effectiveness are studied further for assessing the fin performance. The fin base and tip half thickness along with fin external radius are considered as three design variables. Evaluating the temperature and the thermal stress field through the hybrid spline difference method, the non-dominated sorting genetic algorithm II is utilized in optimizing the problem. The obtained results are analyzed from the angle of a practicing designer.

Cutting fluids play a major role in the metal industry. They are used for having increased material removal rates and increasing the quality of the machined product. The cutting fluids have been used for many decades after their efficacy in increasing productivity was established. Since the advent of cutting fluids the market has flooded with different composition of cutting fluids. All these are mineral oil based and comprise different additives or performance enhancers. However, the latest trend in cutting fluids use is employing vegetable oils as base oil for formulating cutting fluids. Cutting fluids formulated from vegetable oils are a promising source of increasing productivity in the industry because of their thermal properties. It is, however, difficult to formulate stable water-soluble cutting fluid. Also, it has been observed that the chemical constituent of a cutting fluid behaves differently on the surface of the workpiece during machining operation. In this study different cutting fluids were formulated from edible oil and non-edible oil and the performance in terms of temperature was compared and reported.

The materials such as Al 2024-T3, Mg AZ31B, and Ti–6Al–4V are mostly used in various mechanical components that subject to very harsh operating environment. These components may be prone to various kinds of loadings such as impact, blast, and fire. The behavioral study of the response of these components under such loadings is complex due to dynamic nature of the loadings. It becomes more challenging when it is under a thermal environment that means at various temperatures. In the present study, a Continuum Damage Mechanics model is used to predict the behavior of these materials subjected to ballistic impact, blast and fire loading considering various levels of plate temperatures. The temperature and strain rate dependent Johnson–Cook model is implemented in ABAQUS/Explicit using VDLOAD and VDFLUX user subroutines for blast and fire loading, respectively. The localized temperature rises in the plates due to plasticity is studied at various plate temperatures. The comparative investigation is performed by varying plate temperatures and loading conditions. The results can be interpreted for usage of these materials in various aerospace and structural applications.

Redundant manipulators have high degrees of freedom (DOF) which enables the robot to work in cluttered environments. Inverse kinematics (IK) of redundant manipulators have multiple solutions, finding the best solution among the possible solutions is called redundancy resolution. Redundancy resolution can be performed by solving it as an optimization problem, the optimization criterion can be joint distance, joint-torque, and energy consumption. This paper focusses on inverse kinematics, redundancy resolution and trajectory planning of redundant manipulators for pick and place and path traversing applications. Case studies of IK solutions with obstacles in the workspace are shown for 5-DOF planar redundant manipulators. Simulations have also been carried out for redundancy resolution by taking joint distance minimization as objective and reaching the task space location without colliding obstacles, as constraints of the optimization. Results are reported on trajectories in joint space and these ensure smooth end-effector velocities in task space.

Continual interest, recent research, and development in the field of Composite Materials motivated to entitle “Comparative Study of the Mechanical Properties of Al6061 with Graphite undergoing Equal Channel Angular pressing”. The title introduces Equal channel angular pressing process in comparative study. The present work incorporates a stir casting technique in preparation of Al6061 with varying percentage of graphite and further undergoing Equal channel Angular pressing process to compare hardness and corrosion properties between them. This study comprises of comparative microstructural study. The comparative study results showed that the Al6061 with graphite undergone equal channel angular pressing process has increased strength, hardness, weight of material and fine microstructure.

The mechanical behavior of Al7075 alloy composite reinforced with 3%, 6% by weight ratio nanosized B4C particulate is investigated with and without heat-treatment process. The composite is prepared by liquid casting—stirring method and mechanical behavior of alloy Al7075-3% weight (wt) and B4C, 6% wt and B4C nanocomposites were deliberated. Hardness, ultimate tensile strength; yield strength, percentage elongation and compression strength were evaluated and compared as per ASTM standards. The findings yielded in significant enhancement of properties after heat-treatment process. Only percentage elongation of the composite showed declined value relatively.

Hard machining of components has been a new attraction in the field of manufacturing, as it avoids the need for multiple cost inculcation processes for a single part. Hard machining attracts a wide attention to the researchers because of the usage of hard tools, tougher machinery and enormous quantities of cutting fluids. Optimized use of any of these functionaries’ can result in reduction of cost as well as safer and clean working environments. In this research new cutting fluid reduction processes were compared along with the use of hard metal inserts. These two methods suggest an enormous amount of cost reduction along with cleaner shop floor. Minimal quantity lubrication (MQL) and minimal cutting fluid application (MCFA) capacities in cutting fluid reduction as mentioned by various researchers in past two decades. These methods were compared in this research paper for finding out the best possible system. Flank wear is considered as a crucial parameter in hard machining as the wear rate affects other deserving product qualities such as surface finish and job profiles. In this research tungsten carbide coated hard metal inserts were used instead of conventional CBN or diamond tipped tools, which are of higher in price margin. The study comprised of Taguchi’s L9 orthogonal array, which was advised by previous researchers as good tool for optimisation. MQL and MCFA assisted experimentation were performed with same cutting conditions, which were then again compared with dry hard machining and wet machining. Influence of each input parameters where critically evaluated using ANOVA. The results revealed that a promising reduction in tool wear was noticed in MCFA assisted hard machining.

The Vinyl ester (VE) particulate composites find a wide range of applications in chemical industries and wastewater treatment plants, due to their excellent mechanical properties combined with chemical resistance. The present work focuses on the wear resistance of VE composite reinforced with two different fillers materials (i) nano-copper oxide (CuO) and (ii) micrographite (Gr). The fabrication was done by hand lay-up technique by adding different wt% of pure CuO, Gr and hybrid Cuo-Gr into the VE resin with the help of ultrasonicator and magnetic stirrer. The wear behaviour of VE composites was found by using VE composite pin against EN31 steel disc on a computerised pin on disc (POD) operator by varying sliding speed. Effect of CuO and Gr particles on VE composite alters the wear behaviour by changing the morphology. The specific wear rate increases with the increase of wt% of Gr, whereas in the case of CuO, it increases up to 6 wt% and decreases for further addition. The composite containing 5 wt% of Gr and 4 wt% of CuO exhibits highest wear resistance 2.69 m3/N-m. This result shows that the synergistic effect of hybrid filler Gr-CuO is to improve the wear resistance when compared with that of pure Gr/CuO. The micrograph by SEM showed uniform distribution of graphite and copper oxide particles in the VE composites.

Electrical discharge machining is uttermost exploited material removal process broadly used in manufacturing industries for variegate shapes and difficult-to-machine electrically conductive materials. The nascent materials such as metal matrix composites, ceramic composites, duplex stainless steels, and titanium alloys have a vast demand in the area of automobiles, aircraft, aerospace, railways, and micro industries. The machining of these materials using conventional machining process is bonded to linear cutting to overcome this problem EDM was introduced. Many researchers have presented a vast work to understand the material removal mechanism of EDM and conclude that machining performance is mostly affected by process parameters. The machining performance can predict in appropriate way using process modeling techniques. The process modeling of materials like carbon nano-tube reinforced MMC is still needed a lot of research work. This paper includes review of AMC machining and experimental modeling using various methods such as RSM and ANN.

A three-dimensional finite element model has been developed by using ANSYS APDL to study of transient temperature distribution and von Mises stresses during friction stir welding of AA 7075 T651. A cylindrical tool on the workpiece is created. A pilot node has defined on the tool for governing the rotational and translational speed of the tool. Heat is generated due to frictional contact and plastic deformation of the workpiece. Temperature-dependent material properties and friction coefficient were considered in this model. The cooling effect caused by the free convection in ambient air, backing plate and clamping bar is taken into account. It has been observed that temperature profile below the moving tool is an oval shape. It had also observed that the maximum value of von Mises stress has little variation during welding.

This paper presents useful energy (gas and power) production from the three waste biomass (dried grass, leaves, and dead branches) through gasification technology. These waste biomasses were collected in the Indian Institute of Technology Ropar, Punjab and air-dried. The feasibility of the studied biomass for thermochemical conversion process in a downdraft biomass gasifier has been investigated by characterization of biomass. The average higher heating values based on the ultimate and proximate analysis correlation were evaluated as 15.58 MJ/kg for dried grass, 17.075 MJ/kg for leaves and 15.785 MJ/kg for dead branches. The performance of downdraft biomass gasifier has been investigated in terms of calorific valve (3.52 MJ/m3 for dried grass, 5.14 MJ/m3 for leaves and 4.15 MJ/m3 for dead branches) and cold gas efficiency (50.83%, for dried grass, 64.72% for leaves and 59.15% for dead branches). The results show that these waste biomass are a reliable source for energy production through gasification technology having dual benefits of easy waste management and low-cost power production.

Image correlation technique is an optical method based on grey value digital images that can determine the shape, displacement and the strain of an object under load. In this technique, the slope and curvature of a cantilever beam can be obtained based on the intensity values of loaded and unloaded images. According to the conservation principle, for small deformation, the total amount of light reflected for the specified area on the surface would be the same before and after loading when the illumination is unaltered. The method, image correlation technique is obtained on this basis.

For estimation of accurate mode I stress intensity factor in a single edged notched plate, it is important to place the strain gage within a maximum permissible radial distance $$ r_{\hbox{max} } $$ [14]. In the present paper, it is aimed to study how the notch length affects this parameter $$ r_{\hbox{max} } $$. A finite element based procedure is developed based on theoretical formulation analogous to Dally and Sanford technique [16] for cracks. Results show that both notch length and the net ligament length have significant influence on $$ r_{\hbox{max} } $$ and some interesting observations have been reported.

The reasons for the runaway during the nitration of DNT to TNT have been investigated mathematically. All the data required for chemical kinetics has extracted from Kozak’s experimental work. M. M. Khader had proposed a new technique, Picard-Pade method, and this work has been employed in the present work to solve the mathematical model and the results obtained were well substantiated using Kozak’s experimental work. The influence of different mixtures on the temperature growth has been investigated and discussed in detail by dividing the temperature curve into three regions depending upon the change in the slope with respect to time. All the mixture compositions considered were within the range of Orlova’s work. The influence of DNT’s concentration and its dissociation in the presence of sulfuric acid on the runaway reaction has been explained clearly with the numerical solutions. Within the considered mixture compositions, the mixture with controllable temperature growth is a 40–30–18–12 mixture and the mixture with uncontrollable temperature growth is 63–7–25–5. The computational tool used in this work to solve the mathematical model in MATLAB.

One of the promising kinds of renewable energy is wind energy, but not fully exploited till now because of low efficiency of rotors and no power production at slow wind speeds. A vertical axis wind turbine (VAWT) known as H-Darrieus turbine is capable of working efficiently at low speeds and is capable of solving this issue. The design of turbine blade plays an important role in determining the power produced. Multiple experiments involving NACA series of symmetrical airfoils have been conducted to study the performance, but very few studies are available showing the outcome of using the unsymmetrical blade on an H-Darrieus wind turbine. In this paper, the computational study performed on unsymmetrical NACA airfoil blades of varying camber display improved performance. With the increase in camber, the CL value increases up to certain extent, but too much camber can result in decrease in performance.

Formulation and application of cutting fluids with additives and natural oils as based fluids during turning of EN8 steel are discussed in this work. Cutting fluids are developed by dispersing amylum (Amy) in coconut oil (CCO). Performance of biodegradable cutting fluids with amylum is compared with dry machining, SAE grade oil (synthetic fluid), pure oil-assisted machining initially at constant cutting conditions, and varying percentage additive inclusions in base fluid at 0.3, 0.6, and 0.9%. Before machining, the additive dispersed cutting fluids are examined for thermal conduction and absorbance. Cutting temperatures, surface roughness of workpiece, and tool flank wear roughness are tracked and compared for various machining environments considered. It is discerned that thermal and spectral properties have improved for additive-based fluids compared to pure oils. By examination, it is observed that CC + 0.1% additive resulted in best machining outcome by way of reduced cutting tool temperatures, tool flank wear, and surface roughness.

To enhance the efficiency of a machining process, many experiments with several combinations of factors need to be conducted and it is a time consuming and expensive process. Finite element (FE) simulation is the best alternative to reduce the number of experiments. A coupled Eulerian-Lagrangian (CEL) model, which combines fluid and structure is in demand, and it is the nearest representation of the experiment. The present work uses CEL approach to analyse the variation of temperature at shear deformation zones, rake and flank surfaces with and without metal working fluid (MWF) in machining of 420 stainless steel workpiece. The cutting forces were also predicted using these simulations. Some of the simulations were validated with literature and the rest were validated with the experiments. The developed cutting fluid combination was showing a larger reduction in temperature as compared to dry cutting. This methodology will give a scientific base for realistic simulation of the machining process.

This work is dedicated toward the development of the finite element (FE) model based on refined third-order theory (TOT) for the dynamic analysis of functionally graded (FG) beams. Variational approach is employed to derive the governing equations as well as consistent boundary conditions. Two-noded beam element is selected for the discretization of FG beam. The variables $$ u_{0} $$ and $$ \psi_{0} $$ are interpolated using C0-continuous linear Lagrangian functions while the presence of the second derivative of the transverse deflection in the variational equation requires C1-continuity and is interpolated using C1-continuous Hermite interpolation functions. Static deflection and free vibration responses are validated from the literature, and new results have been presented for free and forced vibration of FGM beams.

Polymers are steadily playing a major material role over traditional bearing materials currently being used because of their unique properties including self-lubrication, silent in operation, and less weight. Polytetrafluoroethylene (PTFE) widely known as Teflon is a miracle material in the category of polymers which is found to be best suited for bearing applications. The present work is on tribological behavior of hybrid polymers. Taguchi Orthogonal array is employed for designing the experimental layout. Wear and friction coefficient were measured by pin on disk tribometer. The experimental layout was developed by design of experiments. The difference between the wear and friction values obtained through experimental and mathematical model found to be less than 5%. From the regression table, it is inferred that wear rate is more dependent on load, whereas sliding distance is the most significant factor affecting the coefficient of friction. SEM images were taken in order to study the surface morphology of the PTFE composites, and results have shown that PTFE + Graphite + MoS2 type of composite is more wear resistant when compared to the PTFE + Graphite and virgin PTFE.

Materials development for changing aerospace industry has been the need of time. Composites (metal, ceramic and polymer) materials are proven better than any kind of materials for challenging atmosphere. Aluminium matrix composites (AMCs) are widely used in aerospace applications for variety of accessories. Aluminium composites have good mechanical properties and so they form important materials for structural applications. Processing techniques have an important effect on the overall performance of the AMCs and are directly linked to their mechanical behaviour. This review summarizes the effect of processing techniques, types of reinforcement on the mechanical properties of AMCs.

The wind resource assessment is a decisive process for the development of any wind power generation project. The wind data obtained from any single means may have errors which may lead to the wrong estimation of wind speed and hence the power density. Therefore, the data obtained from any source or method has to be verified and validated with another data source in order to make the resource estimation least erroneous. In the present work, the wind data measured by means of LiDAR and wind mast has been compared with the multiple reanalysis datasets (ERA5, EMD-ERA, MERRA2 and CFSR2) for offshore location in Gujarat, India. From the consequences, the conclusion has been drawn that the reanalysis data provides underestimated wind speeds as compared to LiDAR measurements. Further, among the studied reanalysis datasets, the ERA5 data exhibits highest correlation (0.9329) with the LiDAR measured data, which proves it to be most reliable data source among the other considered reanalysis datasets. The LiDAR measured the mean wind speed of 7.41 m/s at 100 m height, which implies to the mean wind power density of 328.24 W/m2. Thus, the study location is highly suitable for the establishment of an offshore wind power project.