Prediction of Stability and Thermal conductivity of MgO Nanofluids using CCRD Statistical Design Analysis

Magnesium oxide nanopowders were synthesized by chemical reduction method in which sodium hydroxide solution was used as a reducing agent. Magnesium nitrate (MgNO3.6H2O) precursor was used for the synthesis of MgO nanopowders. Solid state characterizations of synthesized nanopowders were carried out by infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. Using two step method, synthesized nanopowders were prepared as nanofluids by adding water and ethylene glycol (55:45). Thermal conductivity measurements of prepared nanofluids were studied using transient hot wire apparatus in which maximum thermal conductivity enhancement was observed in nanofluid. CCRD design has been applied to optimize the performance of nanofluid systems. In this regard, the performance was evaluated by measuring the stability and thermal conductivity ratio based on the critical independent variables such as temperature, particle volume fraction and the pH of the solution. A total of 20 experiments were accomplished for the construction of second-order polynomial equations for both target outputs. All the influential factors, their mutual effects and their quadratic terms were statistically validated by analysis of variance (ANOVA). The optimum stability and thermal conductivity of MgO nanofluids with various temperature, volume fraction and particle fraction were studied and compared with experimental reults. The results revealed that, at increase in particle concentration and pH of nanofluids at certain point would increase thermal conductivity and become stable at nominal temperature.  According to the results, the predicted values were in reasonable agreement with the experimental data as more than 95%  of the variation could be predicted by the CCRD model for thermal conductivity ratio and zeta potential

Mechanical Properties of Luffa Fiber and Ground nut Reinforced Epoxy Polymer Hybrid Composites

AbstractThis paper presents the study of the tensile, compressive, flexural, impact energy and water absorption characteristics of the luffa fiber and Ground nut reinforced epoxy polymer hybrid composites. Luffa fiber and Ground nut reinforced epoxy resin matrix composites have been developed by hand lay-up technique with luffa fiber treated conditions and Ground nut with different volume fraction of fibers as in 1:1 ratio (10%, 20%, 30%, 40% and 50%). Effects of volume fraction on the Tensile, Compressive, Flexural, Impact strength were studied. SEM analysis on the composite materials was performed. Tensile strength varies from 10.35MPa to 19.31MPa, compressive strength varies from 26.66MPa to 52.22MPa, flexural strength varies from 35.75MPa to 58.95MPa and impact energy varies from 0.6 Joules to 1.3 Joules, as a function of fiber volume fraction. The optimum mechanical properties were obtained at 40% of fiber volume fraction of treated fiber composites. Fractures surface of the composite shows the pull out and de-bonding of fiber is occurred

Analysis of formability and twist angle in AA5052 alloy by single point incremental forming process

163-168The incremental forming process is highly characterized by its degree of flexibility and mainly suggested for rapid prototyping. Formability of the sheet metal mainly depends on the properties of the metal sheet, forming process and forming conditions. This paper focuses on the development of FLD for AA5052 alloy at room temperature. In this study a truncated square pyramid is formed by single point incremental process. The formed part was analyzed for its formability and thickness distribution along with the twist induced during incremental forming process. To evaluate the system accuracy a numerical model of a truncated square pyramid is developed by means of FE simulation code Abaqus and validated experimentally. The assessment of finite element simulation with experimental work shows a good agreement between the computed and measured values. The angle of twist is less at lower and more at higher forming heights

Integrating lean and agile practices for achieving global sustainability goals in Indian manufacturing industries

The rising global pressure from stakeholders regarding climate change and its implications for the various aspects of manufacturing have pressured industrial leaders to develop greater environmental responsibility. This has motivated companies and researchers to identify and incorporate various strategies for ecologically sustainable operations. Analyzing the relationship between 'lean' and 'agile' (leagile) practices appears to be a tangible way to become more sustainable, specifically in an emerging economy such as India. The literature has investigated lean and agile practices for enhancing sustainability, although most studies have not adequately framed their analyses of both aspects simultaneously. This limitation of previous studies is the motivation for the present work. The current study expands the scope of previous literature by identifying and prioritizing leagile practices through the lens of sustainability. This study uses a combination of fuzzy set theory and the best-worst method (BWM) for identifying and prioritizing the leagile practices that are effective for Indian industrial leaders. The study is validated for the Indian automotive sector so that industry leaders can implement the requirements of the 'Green India Movement', as recommended by governmental decrees

An investigation into cut surface quality of Al6061/Al2O3/B4C composite using hydro-abrasive machining process

The modern era has realized the tremendous potential of metal matrix composites (MMCs) in slowly substituting the traditional materials used in automotive and aerospace industries. Traditional machining of second generation MMCs is quite challenging due to heat generation, tool wear, and low cut surface quality. This work presents an analysis on hydro-abrasive machining (HAM) of the Al6061/Al2O3/B4C composite by using an amalgamated method of gray incidence based response surfaces (GIRS) to produce a good surface quality. The influence of HAM variables [abrasive flow rate (FA), waterjet pressure (PWJ), jet traverse speed (SJT), and stand-off distance (DS)] on various cut surface characteristics [surface roughness (Ra), striation-free zone (SFZ), striation angle (ΘS), and kerf angle (ΘK)] is examined using L27 OA and response surface plots. A hybrid approach of the GIRS method is presented for necessary polynomial modeling and simultaneous optimization. The reduction of response values is primarily influenced by the waterjet pressure and jet traverse speed. An optimal cutting condition resulted in a significant reduction in surface roughness by 19.22% and striation angle by 10.82%. The improvements in striation-free zone and kerf angle were also notable with reductions of 7.89% and 4.74%, respectively. FESEM images of machined surfaces, profile graphs of surface roughness, and images observed using atomic force microscopy were also studied