Search

Inconel 617 alloy has been included in the boiler and pressure vessel (BPV) code of the American society of mechanical engineers (ASME) for its effectiveness in nuclear applications due to its ability to maintain strength at elevated temperatures. This study is based on the optimization of process parameters for activated flux tungsten inert gas (A-TIG) welding of 10-mm thick Inconel 617 material. Process parameters considered in this study include weld current (A), weld torch travel speed (mm/min), arc gap (mm) and flux powder (silicon dioxide (SiO[Formula: see text] and titanium dioxide (TiO[Formula: see text] combination. The bead on plate welding experiment was carried out by varying the combination of process parameters in each experimental trial. The Taguchi L16 orthogonal array was the design matrix used for the design of experiments (DOE). In the bead on plate welding experiment, a total of 16 experimental trials, each having a different set of process parameters was conducted. The weld bead samples corresponding to each trial were prepared for measurement of the responses which were measured from each of the 16 weld bead samples and included depth of penetration (DOP), bead width (BW), depth to width ratio (DWR), weld cross-sectional area (WA), and bead height (BH). The objective of this work was to maximize DOP, DWR, WA, BH and minimize BW. Analysis of variance (ANOVA) was used to identify the significance of process parameters. Optimization techniques including particle swarm optimization (PSO) and genetic algorithm (GA) were used in the study. The optimized process parameters and optimal solutions attained from each optimization technique were compared. It was found from the study that weld current was the most significant process parameter for all responses followed by weld torch travel speed, flux powder combination and arc gap. Optimal process parameters to achieve maximum DOP, DWR and WA were found to be weld current of 290 A, weld torch travel speed of 50[Formula: see text]mm/min along with an arc gap of 1[Formula: see text]mm and 100% TiO2 as flux. The optimal solution for DOP, DWR and WA was found to be 7.04[Formula: see text]mm, 0.437 and 7.619[Formula: see text]mm2 respectively. The optimal solution for BW and BH was 6.302 and 0.677[Formula: see text]mm, respectively. A confirmation test was conducted to validate the optimal solution obtained from this study. The results from the confirmation test agreed with the solution obtained by optimization techniques.

Tungsten Inert Gas welding (TIG) is preferred in the Aerospace Industry where thin sections have to be welded with quality and precision. But, when thick sections are to be welded, conventional TIG welding is not usually preferred due to low penetration depth necessitating more passes. Activated flux Tungsten Inert Gas (A-TIG) welding was invented to improve productivity when welding thick sections. This study reviews the effects of using oxide fluxes in the A-TIG welding.

An experimental study to measure the evaporation rates, engine performance and emission characteristics of cotton seed biodiesel (cotton seed oil methyl ester) and its blends in different volumetric proportions with diesel is presented. The thermo-physical properties of all the fuel blends have been measured and presented. Evaporation rates of neat cotton seed biodiesel, neat diesel and their bends have been measured under slow convective environment of air flowing with a constant temperature. Evaporation constants have been determined by using the droplet regression rate data. The neat fuels and fuel blends have been utilized in a test engine with different load conditions to evaluate the performance, combustion and emission characteristics of the fuels. The specific fuel consumption values of the two blends, viz. B25 and B75 are found to be same. At the highest load, B0 records the lowest CO volume followed by B100. From the observed evaporation, performance and emissions characteristics, it is suggested that a blend of B50 and B75 can be optimally used in standard diesel engine settings.

This paper aims at presenting a new optimization proposal to enhance the flocculation process in Water Treatment (WT) plant using a better flash mixing, located at KELAVERAPALLY, in Krishnagiri district, Tamil Nadu, India. Further, Sludge removal is done efficiently which decreases the water wastage as well as improvement in output water quality. Though WT plants are already equipped with systematic and sequential physicochemical processes, still they need to be optimized to obtain a better treated drinking water to maintain the quality standards as prescribed by World Health Organization. Chaotic behavior in chemical systems has been used to optimize the performance of WT plant. Measurement systems implemented in WT plant yield several chaotic based measurement parameters which are used to control the system operations to maintain the target water quality. This intelligible data extraction through the proposed measurement  systems in a short span of time improves the plant performance without adding any costly systems except few changes in the existing plant setup.  Chaotic behavior is ensured through Lyapunov Exponents and Kolmogorov-Sinai Entropies. Both, water quality improvement and water wastage reduction is achieved simultaneously in the proposed work when a dosage prediction is done using Feed Forward Neural Networks. The treatment plant investigated has a maximum capacity of 14 MLD (Million litres per day) using two parallel streams with 7 MLD each

In order to degrade the waste dyes, a nanocomposite thin film based on Zinc oxide nanoparticles (ZnONP) and conducting polymer was synthesized by adopting simple ionic layer adsorption reaction( SILAR) method. ZnO was synthesized via green synthetic method by employing cucum sativa fruit pulp an environmental friendly biosolvent which acts as reducing and capping agent. Characterization of the ZnONP reveals enhanced crystallinity, spherical morphology and low bandgap which has a higher influence in the Photoluminescence(PL) quenching of the nanocomposite thin film. The antibacterial activity was performed for green synthesized ZnONP which exhibited better activity due to the presence of oxygen interstitials. ZnO/NaI-PPy thin film exhibited higher conductivity than ZnO/PPy thin film due to the higher mobility of NaI and charge transfer mechanism. The oxygen interstitial in ZnONP is responsible for the reduced PL intensity in nanocomposite thin film. The photocatalytic property of the nanocomposite thin film was evaluated using the degradation of rhodamine 6g dye under visible light. The photocatalytic reaction of the ZnO/NaI-PPy nanocomposite thin film in visible light is 65% higher than that of pure NaI-PPy thin film catalyst.

An experimental investigation of diesel engine performance fuelled with cotton seed oil methyl ester (COME), pumpkin seed oil methyl ester (POME) and its blends with neat diesel using Exhaust Gas Recirculation technique have been carried out. An optimum nozzle opening pressure of 250 bar and lower static injection timing of 20° bTDC is considered as it has been observed that these conditions offer better performance and are lower in emissions. From the experimental results, it could be observed that there is a decreasing trend of emission characteristics of Hydro Carbon, smoke density and NOx for Exhaust Gas Recirculation (EGR) for both COME and POME at full load with respect to blend ratio. The percentage reduction in oxides of nitrogen for B100 COME-EGR is 1.39% and for B100 POME-EGR is 1.11% as compared to B100 conventional method. The percentage reduction in oxides of nitrogen for B25 COME-EGR is 0.94% and for B25 POME-EGR is 0.13% as compared to B25 conventional method at full load condition. The sam...

An experimental investigation of diesel engine using cottonseed oil biodiesel and its blends with exhaust gas recirculation (EGR) techniques has been carried out. An optimum nozzle opening pressure of 250 bar and lower static injection timing of 20° before top dead centre (bTDC) are considered because it has been observed that these conditions only give minimum emissions. From the test results, it could be noted that there is an increasing trend of emission characteristics of HC, smoke density and NOx for both cold and hot EGR for all blends of fuel with respect to brake power. As compared with cold EGR, the hot EGR gives lower emissions at all loads. In hot EGR, among the blends, at no-load and full-load conditions, the B100 gives the highest reduction in NOx of 14.23% and 7.91%, respectively. However, the use of EGR leads to a rise in soot emission because of soot–NOx trade-off for both the cases.