Faculty Publications
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Item Effect of fuel preheating on performance, emission and combustion characteristics of a diesel engine fuelled with Vateria indica methyl ester blends at various loads(Academic Press, 2022) Kodate, S.V.; Raju, P.S.; Yadav, A.K.; Kumar, G.N.The present study examines the preheated (95 °C) and unheated (35 °C) Vateria indica methyl ester (VIME) blends by studying the engine performance, combustion, and emission characteristics at various loads. A single-cylinder, TV1 Kirloskar direct injection diesel engine is used to carry out the tests. Biodiesel produced from Dhupa fat through the transesterification process is used as a renewable fuel in a diesel engine. In this work, diesel (B0), VIME (B100), and two binary blends (B30 and B50) are used. VIME has a higher viscosity, higher density, and lower calorific value than diesel, resulting in lesser brake thermal efficiency (BTE) and higher brake specific energy consumption (BSEC). Due to high viscosity of the biodiesel, preheating of fuel is done before injecting into cylinder. Preheating reduces the viscosity, and enhances the atomization and vaporization of fuel, resulting in improved engine performance. For a given blend of VIME biodiesel and diesel, the preheated blend has better BTE, decreased BSEC and lesser CO and HC emissions, with a slight increment in NOX emission compared to the unheated blend. The preheated B30 blend has a BTE value of 30.3% which is close to the BTE value of 30.1% of unheated diesel at 100% load condition. CO, HC, and soot emissions are decreased by 16.2%, 34.4%, and 16.5%, respectively, for preheated B100 fuel compared to unheated B100, at full load. © 2021 Elsevier LtdItem The relevance of renewable energy and green innovation in environmental sustainability: evidence from BRICS countries(Inderscience Publishers, 2025) Padhan, L.; Bhat, S.The study examines the significance of green innovation and renewable energy usage in reducing the carbon and ecological footprints in Brazil, Russia, India, China, and South Africa (BRICS) countries. It applies a series of econometric techniques and the Driscoll-Kraay standard errors regression approach to data collected between 1995 and 2018 based on the environmental Kuznets curve (EKC) hypothesis. Important macroeconomic control variables, such as industrialisation, urbanisation, financial development, trade openness, and natural resources, are also used to strengthen the model. Empirical results show that a 1% increase in green innovation reduces the carbon and ecological footprint by 0.229% and 0.226%, respectively. Further, increasing renewable energy consumption by 1% decreases the carbon and ecological footprints by 0.024% and 0.032%, respectively. Furthermore, the empirical findings support the EKC hypothesis. The study has important policy implications for governments and policymakers of emerging countries to invest more in green innovation and promote renewable energy. © © 2025 Inderscience Enterprises Ltd.Item Solar-Driven additive Manufacturing: Design and development of a novel sustainable fabrication process(Elsevier Ltd, 2025) Hazoary, A.; Panwar, M.; Singh Rajput, A.S.; Kapil, S.Additive Manufacturing (AM) is revolutionizing industries by enabling layer-by-layer fabrication of complex components. Among AM techniques, Laser Powder Bed Fusion (LPBF) is widely used but is energy-intensive, limiting its sustainability. This study explores the potential of concentrated solar energy as an alternative heat source for sintering Thermoplastic Polyurethane (TPU) in a solar-powered 3D printing process. A custom-designed solar 3D printer, equipped with stepper motors and an Arduino UNO for precise control, was utilized to evaluate critical process parameters such as feed rate, hatch spacing, and layer thickness. The results indicate that feed rate and hatch spacing are pivotal to energy density, directly influencing sintering quality. Optimal sintering occurred at feed rates between 100–200 mm/min, which provided sufficient energy for uniform layer fusion, balancing surface finish and mechanical strength. Larger feed rates resulted in incomplete sintering and weaker parts, while a hatch spacing of 1.67 mm offered efficient pass binding with reduced build time. The study successfully demonstrated the fabrication of multilayer TPU structures using solar energy, achieving mechanical properties comparable to conventional LPBF techniques. This solar-powered approach underscores the potential for integrating renewable energy into additive manufacturing, offering a sustainable alternative to laser-based systems. Future refinements, such as dynamic solar tracking and real-time parameter adjustments, could further enhance its industrial viability. By leveraging renewable energy, this research represents a significant step toward eco-friendly manufacturing solutions, reducing energy consumption and carbon footprint while maintaining high-quality outputs. © 2025 International Solar Energy SocietyItem Durability performance of one-part alkali-activated self-compacting concrete mixes under aggressive and elevated temperature conditions(Elsevier B.V., 2025) Mahendra, K.; Narasimhan, M.C.; Rathod, S.; Das, A.K.; Prakash, G.B.The growing demand for sustainable, high-performance materials in modern construction has driven the development of advanced concrete technologies. This study introduces one-part alkali-activated self-compacting concrete (OPASC) as a practical, safe, and user-friendly alternative to conventional Portland cement-based concretes. Selected mixes with compressive strengths exceeding 70 MPa were evaluated for durability under aggressive conditions, including extended exposure to 5 % sulfuric acid and 5 % magnesium sulfate up to 180 days. The thermal stability of these candidate mixes was also assessed by subjecting the mixes to sustained temperatures ranging from 200 °C to 800 °C. Chloride-ion resistance of these mixes was examined under bulk diffusion tests. Key durability indicators, including water absorption, permeable voids, and sorptivity, were quantified to evaluate matrix impermeability. The results revealed compressive strength losses of 25–32 % under acid exposure, 7–15 % under sulfate exposure, and 30–42 % under thermal exposure, with chloride diffusion coefficients ranging from 0.21 × 10?12 to 0.32 × 10?12 m2/s, indicating high resistance to ionic ingress. The mixes also exhibited low water absorption (3–4.5 %), lower soptivities (0.0024–0.0013 mm/s1/2), and much reduced permeable voids (4.3–5.5 %), reflecting an impermeable, dense matrix. Microstructural analyses using SEM-EDS and XRD revealed that degradation under acid and sulfate conditions is primarily attributable to the decalcification of C/N-A-S-H gels, accompanied by the recrystallization of stable aluminosilicate phases. Finally, the environmental sustainability evaluation, which considered both embodied energy and carbon footprint, verified the superior environmental friendliness of OPASC mixes relative to conventional concrete. These findings confirm that OPASC exhibits superior chemical and thermal durability, reduced permeability, and enhanced resilience, thereby establishing it as a sustainable and practical solution for modern infrastructure applications. © 2025 Elsevier B.V.