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Continuous utilization of crude oil in a diesel engine produces detrimental environmental effects. Therefore use of renewable fuels can at least lower the emission levels because such fuels are recyclable, provide energy safety and significantly deal with social, economic and environment. It is well known that diesel engine have several benefits compared to counterpart petrol engine and produce greater smoke and nitric oxide (NOx) levels. As a result, in this current work an effort has been carried out lower both smoke and NOx emission levels. To achieve this, homogeneous charge compression ignition engine (HCCI) is a better option. The influence of producer gas and dairy scum oil methyl ester (DiSOME) on the thermal efficiency and emission character of a compression ignition engine under dual and HCCI mode has been investigated. The HCCI engine was operated at constant air temperature (80 °C) because DiSOME cannot be vaporized at atmospheric temperature. The obtained with DiSOME-producer gas operated dual fuel mode provided amplified thermal efficiency (BTE) and declined hydrocarbon (HC), carbon monoxide (CO) and marginally augmented smoke and NOx levels compared to HCCI operation.

We are running out of crude oil resources, biodiesel is a promising alternative. However, the usage of biodiesel and its blends are associated with problems in atomization of fuel. The main reason is the high viscosity of oils extracted from green matter. The viscosity of oils is inversely proportional to temperature i.e. as temperature increases the viscosity decreases. Present study discusses the effects of preheated biodiesel and its blends on the performance and emissions of diesel engines. The supply of preheated biodiesel increases thermal efficiency (7.3%) and decreases CO, HC emissions but result in increase in NOx emissions.

In the present-day of world’s economy, the supply of fossil fuels has reduced considerably due to increased growth rate of industrialization and transportation sector. Market economy has a highest impact due to the huge variation in demand and supply of petroleum-based fossil fuels. In this context, biofuels produced from non-edible vegetable seed oil are gaining more attention to use in generators and transportation sectors with less modification in engines. In the present work, Simarouba Oil Methyl Ester (SuOME) is being considered as fuel to run CI engine by advancing and retarding the injection timing (IT). Raw simarouba seed oil is processed and converted to their methyl ester via two stage transesterification process. Use of SuOME at an IT of 190bTDC, 230bTDC, 270bTDC and 310bTDC resulted in Brake thermal efficiency of 24.96%, 25.25%, 26.32% and 25.75% respectively. Reduction in tail pipe HC and CO emissions by 10% and 15% respectively were recorded for engine operating at IT of 270bTDC than standard IT. Marginal increase of NOx by 1.51% was observed due to the increased combustion temperature. Thus, the advancement of IT is a feasible choice to use SuOME in CI engine with higher performance and reduced toxic emission.

In the present work, an effort is carried out to study the effect of load extension in reactivity controlled compression ignition (RCCI) mode of combustion. Compressed natural gas (CNG) and compressed biogas (CBG) are used as low reactivity fuels. Diesel and different blends of thevetia peruviana methyl ester (TPME) are used as high reactivity fuels. The whole experimentation is carried out at 50% and 75% of the rated power. Results showed that RCCI engine operated at 75% load gives higher brake thermal efficiency (BTE) about 29.74% and higher nitric oxide (NOx) emissions along with lower carbon monoxide (CO), hydrocarbon (HC) and smoke emissions. Among various fuel combinations tested D + CNG gives better results in terms of performance and emission characteristics.

A well-known AA7075 alloy used for most of the structural, aerospace, and automobile applications due to its excellent properties such as high strength, corrosion-resistant, and low density. To encourage industrialists, the physical and mechanical properties of the composite has to improve by reinforcing hard ceramic particles. In this investigation varying wt.% of hard ZrO2 (zirconium dioxide) particles (0.75, 1, 1.25, 1.5, 1.75, and 2 wt.%) are reinforced in AA7075 matrix alloy to form a composite. Motorized stir casting technique induced to distribute reinforcement particles homogeneously. The SEM micrographs reveal that uniform distribution of ZrO2 particles can be achieved after inducing motorized stir casting technique into the molten composite. The experimental test results revealed that the addition of ZrO2 particles enhanced the hardness and tensile strength of the AA7075/ZrO2 composite as compared to base matrix material. Among all composites, AA7075/1.5ZrO2 show higher hardness and strength.

Higher fuel economy associated with lower emissions of diesel engines cannot be achieved with conventional low-pressure injection systems. However high-pressure CRDI facilitated diesel engines with electronic control systems can overcome the twin problems of higher emissions of smoke and nitric oxide with acceptable higher brake thermal efficiency as well. Further use of both high-octane fuels like petrol, ethanol as manifold injected fuels along with high pressure CRDI injected high cetane fuels like diesel, biodiesel can successfully overcome the drawbacks of diesel engine emissions. In this direction a newer concept of RCCI operated modified diesel engine was developed in house and was powered with both high octane and high cetane fuels. Comprehensive experiments were conducted on the RCCI engine to obtain its performance, emission characteristics fueled with selected fuel combinations. From the results for B20 and gasoline operation it was concluded that, injection of 10% gasoline drastically reduces the nitric oxide by 6.67% and soot emission by 4.52% compared to diesel mode. However, there was penalty of high hydrocarbon and carbon monoxide emissions by 12.5% and 7.6% respectively.

Experimental tests were performed on homogeneous charge compression ignition (HCCI) with in-cylinder direct injection (DI) of diesel, biodiesel of Ceiba Pentandra oil methyl ester (CPOME) and biodi...

The advantages of common rail direct injection engine, including more power, less noise and vibration, lower specific fuel consumption, precise injection timing and control over the mass of fuel in...

The potential use of aluminium oxide nanoparticles as nanofuel additives was investigated on honge oil methyl ester and diesel fuel blend. The nanofuel blends were prepared by dispersing aluminium oxide in varying quantities in a HOME(B20) (20% biodiesel+80% diesel). Sodium dodecyl sulfate (SDS), an anionic surfactant, was used for a stable dispersion of aluminium oxide nanoparticles in the fuel blends. HOME(B20) fuel with concentration levels of 20, 40, and 60 ppm of aluminium oxide nanoparticles (HOME20, HOME2040 and HOME2060) with varying ratios of SDS surfactants were prepared using ultrasonication technique. The investigated properties of diesel, honge oil biodiesel and nanofuel blends were in agreement with the ASTM D6751-15 standards. The dispersion and homogeneity were established and characterized by using the Ultraviolet–Visible (UV–Vis) spectrometry. The UV–Vis spectrometry results illustrated an increase in absorbance level with a relative increase in the concentration of surfactant. The highest absolute value of UV-absorbency was observed for a mass fraction of 1:4 (Al2O3 NPs to SDS ratio). The investigation was performed at a constant speed of 1500 rpm, and BP of 0 kW, 1.04 kW, 3.12 kW, 4.16 kW and 5.20 kW. The fuel HOME2040 demonstrated an overall improvement in the engine parameters, the brake thermal efficiency (BTE) enhanced by 10.57%, while there was a decline in brake specific fuel consumption (BSFC) by 11.65% and the engine exhaust emission: HC, CO, and smoke reduced by 26.72%, 48.43%, and 22.84%, while the NOx increased by 11.27%. Similarly, the addition of aluminium oxide nanoparticles in HOME(B20) fuel blend resulted in decent reduction in the combustion duration (CD), ignition delay period (ID), improvement in the peak pressure, and a marginal increase in heat release rate (HRR) and cylinder pressure at maximum loading conditions. Based on the experimental results, it is concluded that the aluminium oxide nanoparticles in HOME(B20) fuel demonstrated an overall improvement in the engine characteristics.

Growth in electronic devices comes with a challenge to engineers to provide proficient cooling mechanism in order to evade performance decline. Minichannel heat sinks are one among type of cooling devices to absorb heat formed in the electronic devices. Air is largely employed as cooling fluid in minichannels, but innovative methods are also adopted to enhance the heat transfer during the process. These days with modifications in the fluid flow passage and using liquid coolants such as nanofluids the Nusselt number is enhanced. These structural modifications adopted and different nanofluids employed with various volume concentrations and flow rates passed through minichannels to obtain enhancement in heat transfer rate are compiled in this article. The approach for these investigations is majorly categorized into numerical and experimental works. Numerical studies consisting of wide spread modeling methods like single phase/two phase flow modeling, laminar, transition/turbulent modeling etc. are reviewed. The related in-depth numerical and mathematical models used for computational analyses are detailed out exclusively. Experimental methods consisting of unusual passive techniques such as dimples/protrusions, pin fins, and corrugated channels. to achieve betterment in minichannel thermal performance are also provided. Another prime highlight of this article is compilation (in tabular form) of all the correlations and mathematical models used and developed to analyze different factors/properties during the thermal analyses. This article is concluded by providing an overall idea of different mathematical models and methods adopted in minichannels heat transfer analyses and future aspects to be addressed. Several important areas in minichannels heat transfer analyses exist which demand the optimization of heat and fluid flow processes and the use of machine learning concepts for analysis.

There remains a large scope for new micro filler materials in metal matrix to be used as a composite for structural applications which enhance the mechanical properties of the material. Among the range of available materials for engineering applications metal matrix composites (MMCs) are important engineering materials. Amid the different random reinforcement techniques fly ash is known for its economic viability and near to the ground density factor. Hence composites reinforced with fly ash are an important class of materials. The dispersion characters of filler material are reviewed and studied. Aluminium 6063 alloy was used as the matrix for the fabrication of composites. MMCs were prepared by dispersing fly ash content of 5%, 10%, 15% and 20% by volume of metal matrix. Tensile testing of the samples was carried out. After comparing the composites with aluminium alloy increase in tensile strength of about 58% used for 15% fly ash content was observed. Similar results were obtained when hardness of 10% fly ash reinforced MMC was established 75% higher than parent aluminium alloy. There was also improvement in the wear resistance of the samples compared to its parent alloy. Scanning Electron Microscopy analysis (SEM) analysis was done to observe the dispersion of the fly ash content in aluminium (Al) matrix. Hence enhancement in mechanical properties was observed which are important for structural applications

Reduced cost and mass scale production of nano-composites in the future can provide economic feasibility for realizing their applications. In this work the effect of both synthetic filler graphene (GA) and organic filler henquen fiber (HF) infused in polymer matrix to study mainly the strength aspects for intended structural applications is carried out. This work also aims at determining the effect of nano and micro level reinforcement offered by graphene and HF as individual and combination in modifying the strength aspects for intended structural application. The addition of HF in the control beams was varied from 0.5 to 1% by weight of polymer matrix keeping graphene proportion constant. Dispersion of graphene was carried out by ultrasonic energy. Modified beams were subjected to tensile test to determine the efficacy of the reinforcement. These outcomes were then compared with the plain polymer beams. This study also aims at determining the best combination between these two fillers that leads to optimized mechanical performance. In order to enhance strength of the modified beams an effort was also made to treat natural fibers with alkaline and potassium permanganate treatment as individual and combination. Among the surfactant coatings made the fibers treated with both alkaline and permanganate treatment has shown enhanced results. An increase in the ultimate strength of the composite with a value of 27.13 N/mm2 for 0.5% natural fiber by weight of epoxy resin was noted. An increase in ultimate strength by 74% for graphene filler reinforcement when compared to plane epoxy was recorded. Similarly an increase in strength by 67% was observed when optimized proportions of HF and Graphene were used as reinforcements in holding matrix when compared to plain epoxy samples. Scanning Electron Microscopy was conducted to study the dispersion of these micro and nano fillers in the holding matrix at different proportions.

In this research work, experiments were conducted on a diesel engine powered with dual fuel using neem oil methyl ester, biodiesel and producer gas (PG). A diesel engine was operated with varied co...

With the growing demand of economically feasible, clean, and renewable energy, the use of solar photovoltaic (PV) systems is increasing. The PV panel performance to generate electrical energy depends on many factors among which tilt angle is also a crucial one. Among hundreds of research work performed pertinent to solar PV panels performance, this work critically reviews the role of tilt angles and particularly locating the optimum tilt angle using different methods. The past data collected for analysis can be categorized mainly into mathematical model based, experimental based, simulation based, or combination of any of these. Single-axis tracking, dual-axis tracking, simple glass cover, hydrophobic glass cover, soiled glass, clean glass, partial shadow, use of phase-change material, computational fluid dynamic analysis, etc., are the novel methods found in the literature for analysis and locating the optimum tilt angle. For illustration purpose, few figures are provided in which the optimum tilt angle obtained on monthly, seasonally, and annual basis is shown. Research works are growing in the field of computations and simulations using online software and codes. Pure mathematical-based calculations are also reported but the trend is to combine this method with the simulation method. As the PV panel performance is found to be affected by number of parameters, their consideration in any single study is not reported. In future, work is required to carry out the experiment or simulation considering the effect of soiling, glass material, temperature, and surrounding ambience on the location of optimum tilt angle. As a whole, the optimum tilt angles reported for locations exactly on the equator line, i.e., 0° latitude, ranges between − 2.5° and 2.5°, for locations just above the equator line, i.e., latitude 2.6°–30° N ranges between 5° and 28°, for 40°–70° N, it is 29°–40°, and for 71°–90° N, it is 41°–45°. For locations at 2.6°–30° S, optimum tilt angles range between − 4° and − 32°, 30°–46° S, it is − 33° to − 36°, 47°–65° S, it is − 34° to − 50°, and for 66°–90° S it is − 51° to − 62°.

The analyses of more than 2000 spectro-temporal receptive fields (STRFs) obtained from the ferret primary auditory cortex revealed their dominant encoding properties along time and frequency domains. Results showed that the peak responses of the STRFs were roughly aligned along the time axis, and enhanced low modulation components of the signal around 3 Hz. On the contrary, the peaks of the STRF population along the frequency axis varied and were distributed widely. Further analyses revealed that there were some general properties along the frequency axis around the best frequency of each STRF. The STRFs enhanced modulation frequencies around 0.25 cycles/octave. These findings are consistent with techniques that have been reported in the literature to result in improvements in speech recognition performance, highlighting the significant potential of biological insights into the design of better machines.

The power factor is a significant concern in power systems. The significant power loss occurred due to electronic and electrical equipment damages affected by the deviation of physical characteristics, including voltage, current, and frequency parameters.The power loss and quality issues were resolved by introducing filtering techniques in electronic and electrical equipment. Many filtering techniques include passive filtering (PF), Active power filter (APF), and many hybrid approaches are already available. Most of these methods use proper compensation controlling approaches and failed to minimize the total harmonic distortion (THD), and harmonic mitigation in power systems has its best. In this article, an efficient Hybrid-APF using Artificial-Neuro Fuzzy interface system (ANFIS) for software and hardware perspective is designed. The proposed approach uses hybrid controlling strategies which include PI with artificial intelligence (ANFIS) controller, to control the power losses for H-APF. Additionally, current compensation is achieved by PQ-theory, followed by Hysteresis-Current- Controller (HCC). The hardware architecture of ANFIS with HCC is designed to improve the chip-area for real-time power applications.The present work analyzed by simulating the voltage and current waveform. The proposed-H-APF using ANFIS controller, both software and hardware approaches, is compared with other control techniques like H-APF with PI and Fuzzy logic controller by concerning THD,Reactive power, and Different Harmonics and loads improvements.

Epoxy resins, due to their high stiffness, ease of processing, good heat, and chemical resistance obtained from cross-linked structures, have found applications in electronics, adhesives coatings, industrial tooling, and aeronautic and automotive industries. These resins are inherently brittle, which has limited their further application. The emphasis of this study is to improve the properties of the epoxy resin with a low-concentration (up to 0.4% by weight) addition of Multi-Walled Carbon Nanotubes (MWCNTs). Mechanical characterization of the modified composites was conducted to study the effect of MWCNTs infusion in the epoxy resin. Nanocomposites samples showed significantly higher tensile strength and fracture toughness compared to pure epoxy samples. The morphological studies of the modified composites were studied using Scanning Electron Microscopy (SEM).

The present paper focuses on the effect of nano thin film coating on cutting tool tip for tribological applications. Chemical Vapor Deposition (CVD) technique was employed to coat nano thin film composed of graphene and molybdenum disulphide nanoparticles on to the cement carbide cutting tool tip surface. An optimum design in microstructure of the coating was made to inhibit dislocation because of the difference in the elastic modulus of the two materials used as reinforcements could lead to enhancement in the mechanical properties such as compressive stress, resistance against crack propagation and high thermal stability of the modified composite. An increase in 63% Hardness, 58% Young’s modulus, 56% Elastic recovery and 72% increase in plastic deformation was observed in case of modified tool tips as compared to the cutting tips without coating.