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One of the popular ways to minimise the impact of emissions produced by engines is by enabling alternative fuels. Out of the many trending options for alternative fuels, biogas provides some unique advantages, such as being considered to be environmentally friendly, obeying the laws of renewable energy and generating the smallest carbon footprints. The two major drawbacks of traditional diesel engines are their high rate of NOx and significant amount of soot. The best candidates for overcoming these issues are HCCI engines; HCCI engines can provide better control over NOx generation and overall thermal efficiency can be improved to a greater level. These types of engines are compatible with both SI and CI. Now, to understand and analyse the behaviour of HCCI, the present work was focused on a modified single-cylinder CI engine. It was made to operate in HCCI mode by enabling the combination of biogas, along with diethyl ether (DEE), as a fuel mixture. To achieve better combustion, biogas was combined with air, while DEE acted as an ignition source, which can be introduced at three different locations. In total, the experiment was performed sixty times so as to achieve the best injection position. To obtain this information, other parameters, such as biogas flow rate, torque, methane fraction and DEE injection position, were also incorporated. The main results were consolidated by warping the output parameters such as brake thermal efficiency, equivalence ratio, air–fuel ratio, and brake-specific fuel consumption. Emission such as CO, HC, NOx, and smoke were taken into account. The results indicate that port injection provides higher thermal efficiency than manifold injections, while lower emissions were observed in manifold injections.

In recent years, composite materials such as carbon-fibre-reinforced plastic (CFRP) have been widely used in medical devices, industries, marine and aerospace applications due to their high resistance-to-weight ratio toughness, corrosion resistance, and other novel properties. The machining of these composite materials using conventional machines results in poor precision and surface finishing due to excess heat generation at the tool-material contact zone. The drawbacks of the conventional machining process can be overcome with the adoption of a novel cutting technique using pressurized water, which can dissipate the heat generated by the impact of abrasive particles against the material in order to eliminate the poor precision and surface finishing caused by overheating. In this experimental study, the performance of surface quality (roughness and kerf angle) of CFRP machining using an abrasive water jet technique has been studied for a wide range of cutting parameters, such as water pressure and cutting speed.

Air transport is very frequent to assure worldwide social connection and commercial purposes. The use of aviation fuel demand on huge amounts becomes tensed due to the depletion of fossil fuel. Furthermore, the greenhouse emission offering vigorously by fossil fuel reduces the environment quality and human life. Therefore, it is clearly coming on priority to get attention towards alternative aviation fuel from renewable sources. However alternative fuel must be compatible with the conventional fuel in terms of its physical properties such as viscosity, energy density, sustainability, affordability and availability. The comparison to replacement of conventional fuel by alternative fuel motivates to study the properties. Measurements of Atomization spray characteristics of aviation fuels followed by comprehensive properties for a clear figure. This study is about to study the procedure to examine fuel and blends properties by developing spray atomization.

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This study presents experimental and numerical works on porous media burner. The influence of ultra-low vegetable oil droplets on burner performance was investigated. A unique dual-layer microporous media burner was fabricated to generate surface and submerged flames under lean conditions. Optimum equivalence ratio under lean conditions for surface and submerged flames was recorded at 0.7 and 0.5, respectively. The performance of the burner was examined by adding vegetable oil droplets of 20, 40, 60, or 80 $$\upmu \hbox {L}$$ externally on the surface of reaction layer. At 80 $$\upmu \hbox {L}$$ , the burner was at its best performance, while $$>80 ~\upmu \hbox {L}$$ leads to unstable flames. The maximum thermal efficiency of the burner under surface flame without droplets was found out to be 90%, which was enhanced to 94% by enabling 80 $$\upmu \hbox {L}$$ of vegetable oil. Similarly, with submerged flame maximum thermal efficiency progressively improved from 38 to 45%. The impact of vegetable oil at the microscopic level was determined by performing scanning electron microscopy and X-ray diffraction analysis. Digital thermal images were captured at critical ER to ensure a stable combustion. The emitted combustion gases were monitored continuously to detect the emissions (NOx and CO). These emissions were within controlled limits. Finally, three-dimensional numerical study was performed to effectively comprehend the experimental data for both temperature and emissions.

Adding varieties of nanoparticles to the base fluid is a recent technique for boosting the thermal performance of mono-nanofluids and conventional fluids. The main intension of this article is to investigate the forced convection heat transfer of water-based Al2O3 nanofluid and Al2O3 + graphene hybrid nanofluid numerically. Selected volume concentrations of Al2O3/water nanofluid (0.3, 0.6, and 1.0 vol%) has been compared with Al2O3 + graphene hybrid nanofluid. The working fluids were tested in three different sizes of mini tubes, i.e., 2.1, 1.1, and 0.8 mm. The homogeneous model was breezed to simulate the hybrid nanofluids. Thermophysical and rheological properties of the nanofluids were taken from standard experimental tests which are available in the literature to validate toward computational study. The results clearly indicate usage of Al2O3/water nanofluid greatly enhances convection heat transfer performance in mini tube. A high enhancement in heat transfer coefficient by adding 0.0175 vol% graphene nanosheets was performed in simulation, which provide a range between 12.7 and 13.7% over Al2O3/water nanofluids. However, the divergence of impact for adding graphene on Al2O3 nanofluids was marginal with change in mini tube sizes. Moreover, extra penalty in pressure drop was noted.

Superfinishing is one of the methods of high-quality surface machining of elements subjected to high surface wear. It is used for machining external and internal cylindrical surfaces using various models of tools. This experimental study was aimed at determining the effect of machining parameters on surface roughness of high-quality alloy bearing steel. The factors considered were angle of crosshatch pattern (realized by the rotational speed at constant velocity and oscillation), machining time, and pressure of the tool on the machined surface. The experiment was carried out according to the analysis planned for two tools with granulations of 500 and 800. The polynomial and exponential regression equations for subsequent roughness and performance parameters were determined statistically. The multidimensional correlations based on the t-student distribution were established. The results showed that the optimum surface quality depended on the process parameters: grain size, machining time, crosshatch angle, and the contact pressure. The time at which the machining process starts to stabilize with a steady surface roughness was determined to be 120 s. The maximum enhancement of surface roughness was 75% for crosshatch angle of 13°, contact pressure of 0.21 MPa, and granulation of 800. For both 500 and 800 granulations, the diameter loss was in the range of 1–12 microns.

The study of fluid flows in a cavity and their effect on thermal performance in heat transporting and entropy generation are found in many heating and cooling engineering applications such as energy storage geothermal reservoirs, boilers, solar collectors, underground water flow, lakes, nuclear reactors. This paper presents a comprehensive review of the recent numerical and experimental studies on both heat transfer and entropy generation and their applications in cavities. The effect of the fluid thermal properties, the cavity configuration, the boundary, and initial conditions, the magnetic field, the thermal source discretion, and other geometrical and physical parameters on heat transfer and entropy generation are discussed. This study also presents the effect of several important dimensionless parameters such as the Reynolds, Richardson, Grashof, Rayleigh, Darcy, Hartmann, and Prandtl numbers on both natural and combined convection heat transfer mechanisms in cavities.

Increasing the count of transistors packed within integrated circuits necessitates efficient communication architecture such as Network-on-Chip (NoCs) to deal with scalability, bandwidth, latency, and optimized CPU core utilization goals. To extend the applicability of Moore’s law, multiprocessor architectures have been introduced, which in turn requires a higher level of synchronization and concurrency to enable enhancement in system performance. This research deals with global communication for NoC-multi-core system using the Intelligent Adaptive Arbitration technique to enable task parallelization by showing a perspective for the deployment of Intelligent Adaptive Arbitration on different NoC architecture(s) to enable parallel computing with fair bandwidth distribution and low latency. This research also opens up room for the various network-on-chip topology to constitute a unification of the latest trends of intra-chip communication.

Air transport is already a well-known transportation in assuring the need of worldwide social connection and commercial purposes. Nowadays huge demand on aviation fuel increases severe tense due to depletion of fossil fuel. Furthermore, the increases of greenhouse gas emission from the fossil fuel reduces the environment quality and human life. Hence, an attention towards alternative aviation fuel from renewable sources has become a priority as it could offer greener aviation. However alternative fuel must be compatible in comparison of the conventional fuel in terms of its physical properties such as viscosity, energy density, sustainability, affordability and availability. Those properties will affect spray characteristics and leads to combustion quality. Therefore, this study presents a review on the different alternative fuels and their compatibility in the aircraft engine. The importance of spray characteristic on the engine and different experimental approach to examine the spray characteristics of fuel particularly the penetration length, spray morphology, cone angle and atomization of the fuel also are presented. This work is beneficial in providing understanding on alternative fuels and spray atomization examination.

One of the popular ways to improve thermal efficiency of porous media burners is by enabling smart materials in reaction zone. In this experimental work, a predefined bilayer porous media micro burner was made to achieve both surface and submerged flame for a foam type (Alumina) of reaction layer and compared with conventional style of using discrete type. Moreover, preheat layer was also made up of foam (porcelain), which helped in attaining stable flame. This work mainly aimed to show burner behavior from rich to lean region at critical equivalence ratios. During surface mode combustion highest temperature was recorded for foam type was at equivalence ratio of 1.1, while discrete type was 1.3. Similarly, submerged mode combustion reordered maximum temperature for both foam and discrete type was around 0.6. Finally, thermal efficiencies where calculated at suitable equivalence ratios and emitted emission from the burner tip was also taken into considerations.

Ever increasing usage of fossil fuels and dwindling natural resources led researchers to concentrate on investigating other sources which can satisfy our demands and reduce pollution levels. Present research work aims to investigate the performance and emission characteristics of plastic, diesel and biogas as fuel blend operated in a dual-fuel engine with biogas as a primary fuel and plastic oil – diesel blends as secondary fuel and also predict the output variable using artificial neural network. A modified four-stroke single cylinder CI engine was used for experiments conducted at varying load, percentage of plastic oil percentage in diesel and biogas flow rate. Based on the levels and factors a Taguchi L9 orthogonal matrix was designed to find the optimal combination of input indices. The signal to noise ratios in taguchi method were applied based on the desired output characteristics and according to the respective SNR ratios an ANOVA table was created to determine the major contributor effecting output parameters such as brake thermal efficiency, CO, HC NOx and smoke emissions. ANN model helped to predict BTE with same input parameters but with an increased set of sample data. Based on Gradient descent and Levenberg-Marquardt algorithm the ANN architecture was trained, validated and tested to predict the response with least error. The ANOVA calculated indicates load to be the prime factor effecting BTE and NOx emission

This research paper presents a computational and analytical investigation of aerodynamic derivatives in an oscillating wedge. Unsteady hypersonic similitude has been apprehended for an oscillating wedge with an attached bow shock at a large incidence angle. The problems of instability and shock waves are generally associated with hypersonic flow and, therefore, it is imperative to evaluate aerodynamic models that can solve these problems. Lighthill’s piston theory is an unsteady aerodynamic model that is valid for an oscillating wedge with an attached shock wave. The analytical solution verifies that both the stiffness and the damping derivatives attain high values when the semi-vertex angle of the wedge is increased, while both derivatives assume lower values at increasing Mach numbers. Similarly, the pressure distribution over the wedge is evaluated to determine the details of how the developing flow cause the instabilities. Our study presents the contour plots of pressure, temperature, density, and Mach number that unravels the positions of flow separations in an oscillating wedge model.

The applications of porous media burners are of massive interest to researchers from decades, and still trending in the modern world because of their tremendous advantages, such as high thermal efficiency and low emissions. In this work, a microburner was made to achieve surface and submerged flame region for different thicknesses of preheat layers. A reaction layer of alumina foam with a predefined thickness was used, whereas the preheat layer of porcelain foam was replaced with three different thicknesses namely 5, 10, and 15 mm. By using 5 mm preheat layer, only surface flame was visible with absolutely no trace of submerged flame region, while 10 and 15 mm can undergo both surface and submerged flame region. Equivalence ratio of 0.7 was observed to give best performance with regards to surface flame, while 0.5 for submerged flame region. Only 10 mm can able to give highest thermal efficiencies reaching 90% and 38% for the surface and submerged flame region respectively. Finally, low emission rate for NOx and CO was seen for all the possible individual cases.

This paper presents an experimental study of airflow from convergent-divergent nozzles discharged into enlarged duct, focusing attention on the flow development in the duct. To investigate the influence of active control on the flow field developed in the duct, the micro jets of 0.05 mm radius orifice placed at 900 interval along the base at 6.5 mm from the main jet were employed. The Mach number of this study was 1.3. The area ratio of the present study was 2.56. The NPR presented are from 3, 5, 7, 9, and 11 respectively. The L/D ratio of the duct was varied from 10 to 1. The level of expansion at the nozzle exit influences the wall pressure very strongly since in the present case all the NPRs of the tests are under expanded. For all the L/D the entire flow field in the duct is full of waves, the few shock wave is so powerful that the wall pressure is equal to the atmospheric pressure or more. At L/D = 3, it is seen that due to the influence of the back pressure the number of compression and expansion waves have reduced drastically. The flow field with and without control is identical.

FMECA is the name of a widely utilized tool in diverse areas which based on the assessed potential failures, provides a foundation of remedial measures. Due to utilization of an expert team for evaluation of system failures, numerous methods for aggregating of opinions were proposed; which confronting with uncertainty and incomplete analysis of system have been two continual problems. In this paper, a new FMECA model based on fuzzy logic and Dempster-Shafer theory (D-S theory) is proposed to evaluate the risk in FMEA. The proposed model is development of a recent fuzzy rule-based model with 100 membership functions, which a novel linear equation (Gupta-Ghasemian formula) is discovered through it. By contributing of the generated formula to FMEA, a more useful method which provides a unique result for any combination of risk factors aiming at capturing of uncertainties is presented. As the case study, an industrial centrifugal pump is assessed by a FMEA team comprised of ten experts who were experienced in industrial components. Finally, according to the results, failure modes are ranked and critical components are recognized.

The main content in the kinematics of machinery course includes kinematic analysis of machines and mechanisms and forms an integral part of the mechanical engineering curriculum. The conventional way of teaching students about the machine mechanisms is either by lecture notes/PowerPoint presentations/blackboard sketches finds it challenging to get an overall concept. Students find it challenging to understand the movements of machine parts due to a lack of visualization. The course can be taught in much lucidly and persuasively way by physical models or virtual mechanisms in a software ecosystem. There are several commercial and free software exists that can be used to complement the teaching and learning. In this paper, more straightforward, and more intuitive CAD software is reported, which has a very simple to use interface and a swift learning curve. A user can appreciate why and how the mechanism works by simulation of various mechanisms through CAD software.

Calcite-Zincite nano particles were synthesized by Sol-Gel Auto Combustion (SGC) technique. Modifying nanoparticles promote numerous advantages, such as, simplicity of synthesis, small heat for breakdown, regulation above the compound structure, small budget, dependability, repeatability, and moderate synthesis situations. One of interesting study on Sol-Gel auto Combustion technique has proven massive advantages as compared to other traditional methods. Presented work follow synthesized of novel nanoparticles. Research work was focused on characterized UV visible absorption spectroscopy and FTIR. The UV visible absorption spectroscopy shows an absorption band at 214 nm, 234 nm and 372nm due to calcite/zincite nano composite particles. FTIR spectra establishes a particular Calcite - Zincite nano powder obtained the characteristic peak of carbonate group at 1414 cm-1, 868 cm-1 (CaCo3) and 477 cm-1 (ZnO).

Palm oil industry plays an essential role in South-East Asian agricultural commodity sector as it contributes to the substantial gross domestic product of the country. However, with the advent of climate change and massive deforestation, the disease and malfunctioning in growth of palm tree has increased. Therefore, it has become essential to detect any form of disease in palm oil plantation which can hamper its productivity as it can cause a serious problem to the countries whose economic conditions are primarily dependent upon palm oil plantations. Hence, early detection of disease from the initial stage is crucial to the production of palm oil. In this regard, the proposed manuscript highlights the importance of image processing in detecting early disease in palm oil plantation using image segmentation and also proposes some improvisations in palm oil plantation which will be helpful in managing the palm oil commodity business.

The authors aimed to look into the viscosity investigation of mono and hybrid Aluminium Oxide/Silicon Oxide (Al2O3/SiO) based nanofluids. The viscosity methods were carried out for mono nanofluids as well as hybrid nanofluid, which are suspended in base fluid (water). Both mono and hybrid nanofluids of Al2O3/SiO were developed in concentration, which vary from 0.01% to 1.00%. The methodology invoked for viscosity measurement was done by spindle rotation technique, which uses Anton Paar RheolabQC rotational rheometer at temperatures of 30 - 70 ° C. The results imply that viscosity of nanofluids was directly proportional to volume concentration and temperature.

Unsaturated polyester (UPE) composites filled with coconut shell (CS) powder was prepared by compression molding technique. To improve the mechanical and physical properties of CS-UPE composites, titanium dioxide (TiO2) filler was added. CS also undergo two types of chemical treatment which were alkaline (NaOH) and silane treatment. Fourier transform infrared (FTIR) was used to investigate the changes of fibers chemical constituents after the two chemical treatments have been done. CS-TiO2-UPE composites was characterized with physical testing (density, water absorption and thickness swelling), mechanical properties (tensile and flexural test) and scanning electron microscopy (SEM). Overall, the result shows that, the presence of CS and TiO2 filler in UPE composites demonstrated the highest density. For water absorption and thickness swelling study, it was observed that the treated CS-UPE composites showed lower water absorption properties in comparison to those of untreated CS-UPE composites. The presence of TiO2 filler showed an increased in those water absorption properties but still low compared to CS filled UPE. Both chemical treatment of CS caused a significant increase in the tensile and flexural properties. The presence of TiO2 filler demonstrated a significant improvement in modulus properties but at the expense of strength properties. SEM investigation has shown that the surface modification of CS has better fiber-matrix interaction. Thus, chemical treatments on the CS improve fiber/matrix adhesion of UPE composites.

Occurrence of combustion phenomenon in porous media has always excited researchers to develop various shape and size of burner so that maximum utilization of energy can be taken achieved. Here in this experiential work, dual layer micro burner was exclusively built to carry out porous media combustion characteristic with different type of discrete material in reaction zone. Presently, only alumina and zirconia are compared in discrete form, while preheat layer was made of porcelain ceramic material (foam type). Reaction zone was restricted to thickness of 20mm while preheat zone at 10mm. A concept of equivalence ratio was aided since it involves premixed combustion of air and butane as fuel mixture. Additionally, burner was made to run under lean to ultra-lean modes and finest temperature were recorded. Both surface and submerged flame was generated effectively. Maximum temperatures recorded during surface and submerged flame condition was better by installing alumina rather than zirconia there by reaching a value of 631°C and 470°C respectively. Thus maximum thermal efficiency was calculated and found out to be 84%. Finally, emission parameters like NOx and CO where monitored and found out to be well within acceptable limits.

The applications of porous media burners are of often keen interest to researchers because of many modern advantages, such as high thermal efficiency, stable flame and low emission rate. In this current experimental work, a microburner was made built to achieve both surface and submerged flame for three different thicknesses of reaction layers. A reaction layer of discrete alumina with a predefined thickness of preheat layer was used for combustion. Reaction layer was accordingly replaced with different thicknesses of 10mm, 20mm and 30mm. This work mainly aimed to show burner behavior with increase in thickness of reaction layer thus suggesting the optimum equivalence ratio from best burner performance. Interesting and unique behavior of the burner was encountered for each thickness of the reaction layer. Highest surface temperature was found out with 10mm of reaction layer, while highest wall temperature was incorporated with 20mm of reaction layer. Equivalence ratio of 0.3 is best suitable for optimum p...

Behaviour of porous media combustion is mainly relay of material used in reaction and preheat zone to possesses high thermal efficiency. Present study deals development of porcelain foam porous media which shall acts as preheat zone to obey peclet number. While in reaction zone consist of alumina foam. In a dual layered micro burner the thickness of reaction and preheat zone was kept at 15 and 10 mm respectively. Burner was developed to achieve not just conventional free flame but also generate submerged flame, varying equivalence ratio (ER). Further, premixed combustion performance was enhanced by running ER below 1, which is lean condition. While optimum ER for surface flame and submerged flame was found to be 0.7 and 0.5 respectively. Maximum thermal efficiency during for surface and submerged flame was turn out to be 90 % and 38 % respectively.

Porous media combustion is considered to be one of the popular choice due to its tremendous advantages. Such type of combustion liberates not only super stable flame but also maintains emissions parameters below thresholds level. Present study incorporates reaction and preheat layer with discrete and foam type of materials respectively. Burner was made to run in ultra-lean mode. Optimum equivalence ratio was found out to be 0.7 for surface flame, while 0.6 during submerged flame condition. Maximum thermal efficiency was noted to be 81%. Finally, emissions parameters where recorded continuously to measure NOx and CO, which were under global limits.