http://localhost:8080/xmlui/handle/123456789/217 2026-04-26T08:14:37Z 2026-04-26T08:14:37Z Ojha, Shakuntala Acharya, Samir Kumar Raghavendra, Gujjala http://localhost:8080/xmlui/handle/123456789/3258 2025-05-02T09:43:07Z 2015-01-01T00:00:00Z

Title: Mechanical properties of natural carbon black reinforced polymer composites Authors: Ojha, Shakuntala; Acharya, Samir Kumar; Raghavendra, Gujjala Abstract: This article describes the development of new carbon black material from agricultural waste (wood apple shells) by usingpyrolysis method at various carbonization temperatures (400, 600, and 800 C) and used as reinforcement in polymer composites.The wood apple shell carbon black (WAS-CB) particulates are characterized by proximate analysis, energy dispersive spectroscopy(EDS), and scanning electron microscope (SEM). Results showed that due to increases in carbonization temperature the percentageof carbon improved in the carbon black particles. Furthermore, various tests were performed to determine the effect of new carbonblack material on the mechanical properties of composite at different filler loading. The results indicated that mechanical propertieslike tensile strength, tensile modulus, flexural strength, and flexural modulus are improved as the increase in the carbonization tem-perature and filler loading. The filler-matrix bonding was analyzed by SEM. Description: NITW

2015-01-01T00:00:00Z V R K, Raju http://localhost:8080/xmlui/handle/123456789/3228 2025-02-26T10:00:53Z 2014-01-01T00:00:00Z

Title: Taylor vortices in the flow between two coaxial cylinders one of which has a step change in radius Authors: V R K, Raju Abstract: A numerical study of the flow between two coaxial cylinders, where one of the cylinders has a step change in radius, is carried out. The inner cylinder rotates and the outer cylinder is stationary. Computation is restricted to axisymmetric motion since instability in flow between coaxial cylinders is found to first occur in the form of axisymmetric Taylor vortices. In the presence of a step, Taylor vortices are found to appear first in the region where the gap between the cylinders is larger and approximately when the local Taylor number in this region reaches the critical Taylor number for onset of instability. Subsequently, Taylor vortices appear in the region where the gap is narrower, and when the local Taylor number in that region exceeds the critical Taylor number. The Taylor vortices have inward flow at a stationary end plate, and outward flow at an end plate which rotates with the same angular velocity as the inner cylinder. Similar results were obtained by Sprague et al (2008 Phys. Fluids 20 014102) for a step on inner cylinder configuration. The step functions as another end plate, if the step size is large. Whereas, it has no effect, if the step size is small. In most situations, these determine whether the number of Taylor vortices in the wide and narrow gap regions is even or odd. When the end plates rotate synchronously, but at a different speed from the inner cylinder, a change from even to odd or odd to even number of vortices in each region occurs at certain rotation rates of the end plates by sudden appearance or disappearance of a vortex at the end of the column. For a certain range of rotation rates of the end plates, the total number of vortices in the entire fluid column is odd, although the end conditions are symmetrical. Description: NITW

2014-01-01T00:00:00Z Raj Kumar Gupta, Raj Kumar K. A., Sankeerth T., Karthikeya Sharma G., Amba Prasad Rao K., Madhu Murthy http://localhost:8080/xmlui/handle/123456789/3227 2025-02-26T09:57:28Z 2014-01-01T00:00:00Z

Title: Effects of Water-Diesel Emulsion on the Emission Characteristics of Single Cylinder Direct Injection Diesel engine - A Review Authors: Raj Kumar Gupta, Raj Kumar; K. A., Sankeerth; T., Karthikeya Sharma; G., Amba Prasad Rao; K., Madhu Murthy Abstract: Diesel engines generate undesirable emissions during the combustion process. Various control methods have been developed to reduce nitrogen oxides (NOx) and particulate matter (PM) emissions from diesel engines so that the strict emission regulations can be fulfilled. Oxides of nitrogen (NOx) and particulate matter (PM) are the main pollutants from diesel engines and it has been proven that the method of introducing water with fuel to be a powerful and economical technique for reducing these pollutants. Water-Diesel emulsion is a new type of fuel which can be used in place of diesel fuel for the purpose to get the reduction in emissions of diesel engines. Many studies have been done on emulsion fuels and have concluded that this technique has the potential to significantly reduce the formation of NOx and PM and improve combustion efficiency. The emulsified fuel contains water and diesel fuel with some suitable surfactants to stabilize the system. An important aspect pertaining to water-diesel emulsion as a fuel for diesel engines is that it can be used without any modification in the existing engine. This paper presents an overview of recent progress in research of using water-diesel emulsion for the purpose of improving emission characteristics of a single cylinder direct injection diesel engine. Description: NITW

2014-01-01T00:00:00Z Ojha, Shakuntala Gujjala, Raghavendra Acharya, Samir Kumar http://localhost:8080/xmlui/handle/123456789/3224 2025-02-26T06:28:45Z 2014-01-01T00:00:00Z

Title: Effect of Filler Loading on Mechanical and Tribological Properties of Wood Apple Shell Reinforced Epoxy Composite Authors: Ojha, Shakuntala; Gujjala, Raghavendra; Acharya, Samir Kumar Abstract: During the last century, natural fibers and particulates are used as reinforcement in polymer composite that has been continuously growing in the composite industry. This polymermatrix composite haswide range of applications in hostile environmentwhere they are exposed to external attacks such as solid particle erosion. Also, the mechanical properties of different polymer composites show the best alternate to replace the metal material. In the present investigation, an attempt has been made to improve the mechanical and tribological behaviour of polymer matrix composite using wood apple shell particles as a filler material in polymer matrix. Also the temperature variation of the dynamic-mechanical parameters of epoxy matrix composites incorporated with 5, 10, 15, and 20 wt% of wood apple shell particles was investigated by DMA test. It is clearly observed that the incorporation of wood apple shell particles tends to increase the tensile strength, flexural strength, erosive wear resistance, and viscoelastic stiffness of the polymer composite. To validate the results, SEM of the polymer matrix composite has been studied. Description: NITW

2014-01-01T00:00:00Z