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ThesisItem Open Access Fabrication and characterization of novel liquid rubber modified epoxy(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-11) Gunwant, Dheeraj; Sah, P.L.A series of liquid rubber modified epoxies (LREs) were fabricated by dispersing pyrolysis derived liquid rubber (PLR) with concentrations ranging 0-25 wt. % into a commercially available epoxy resin (CY-230) followed by curing with triethylene tetramine (TETA, HY-951). The qualitative dispersion of PLR into cured epoxy was ascertained through atomic force microscopy (AFM) and DC conductivity. The nature of bonding of PLR with epoxy was studied using FTIR spectra. The LREs were cast into different dimensions according to ASTM D specifications. The effect of PLR on their mechanical and thermal properties has been evaluated. With PLR concentration, a regular decrease in hardness, tensile, flexural and compressive properties has been observed. This is attributed to the increase in size of phase separated rubber particles (RPs) as well as plasticization of epoxy matrix due to PLR addition. The impact strength and fracture toughness (KIC) of LREs improved gradually up to 15 wt. % of PLR concentration. This is attributed to the increase in size of plastic zone due to the presence of in the LREs. In order to correlate the improvement in impact strength and KIC values, specimens recovered from these tests were subjected to fractography using FESEM. Cavitation of RPs followed by shear yielding of epoxy matrix was observed to be the most prominent toughening mechanism in LREs. The effect of PLR on thermo-oxidative stability of cured epoxy as well as LREs was investigated through simultaneous thermogravimetric-differential thermal analysis-differential thermogravimetry (TG-DTA-DTG). Micromechanical modeling of LREs was conducted using a finite element (FE) model assuming bcc arrangement of RPs in epoxy matrix. The model was used to explain the lowering of stiffness using a novel scheme based on isotropic stiffness matrix and numerical homogenization technique (NHT). The model was employed to substantiate the experimental findings through stress analysis. Finally, the model was used to predict the effect of RP properties on the elastic properties and stress distributions in LREs.ThesisItem Open Access Thermo-hydraulic performance studies on solar air heater having rectangular sectioned tapered rib-roughness(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Gupta, Akash Deep; Varshney, L.ThesisItem Open Access Parametric studies on thermal regenerator for VOC incineration(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2015-08) Dalakoti, Akansha; Murthy, D.S.Volatile organic compounds (VOCs) are the most common air pollutants which plays a significant role in creating an environmental imbalance. VOCs are one of the main sources of photochemical reaction in the atmosphere leading to various environmental hazards. Thermal oxidation is the only viable method for controlling toxic and other certain harmful air pollutants. Regenerative thermal oxidation incorporating two regenerators is quite effective in VOC incineration process. In the present work a mathematical model has been studied using the computer code developed in Fortran language. Present work deals with study of various operating parameters like particle diameter, bed cross sectional area and cycle time for different xylene concentrations. Temperature distribution in the bed for different particle diameters and bed cross sectional area is analysed. Effect of particle diameter and bed cross sectional area on regenerator bed length is also studied. Bed length is optimised in each case for attaining operative oxidation temperature of 8600C. Effect of cycle time on average exit temperature of hot gas as well as thermal heat recovery (TER) is also discussed. It is observed that with increase in particle diameter regenerator bed length increases and with increase in bed cross sectional area it decreases. TER remains constant with increase in particle diameter as well as bed cross sectional area. Increasein cycle timeincreases average exit temperature of hot gas which in turn reduces TER. TER remains constant up to cycle time of 600s but after that it starts reducing. The increase in xylene concentration after 1200 ppm significantly reduces TER as well as bed length for corresponding particle diameters and bed cross sectional areas.ThesisItem Open Access Performance and emission characteristics of a CI engine operating on pine oil-n-butanol-diesel blends(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Singh, Kailash; Gupta, V.K.In the present investigation, pine oil and n-butanol blends are used as an alternative fuel for diesel engine. The pine oil is non-edible forest based less viscous oil, which is produced by steam distillation of pine resin and pine needles. Pine oil is rich in high energy content and the production of pine oil does not affect main cultivation land and edible supply. n-butanol is a primary alcohol which has better fuel properties like energy content, kinematic viscosity and cold flow properties compared to methanol and ethanol. In the present study n-butanol is used because of its higher oxygen content and cold flow properties. Diesel fuel is taken as reference fuel in present study. The measured fuel properties of test fuels are found comparable with the diesel fuel. Performance and emission characteristics of a single cylinder, four stroke diesel engine of rated 1500 rpm, are investigated at different engine loads. The engine performance parameters such as fuel consumption and brake specific fuel consumption are decreased with addition of pine oil, however, average brake power and brake thermal efficiency has been increased. Exhaust gas temperature is found higher, while smoke emissions are improved for pine oil-diesel blends, as compared to diesel. When n-butanol is added to pine oil-diesel blends fuel consumption rate, BSFC, average brake power and brake thermal efficiency is increased. Exhaust gas temperature is reported higher at higher percentage of n-butanol, while smoke density reduced significantly for pine oil-n-butanoldiesel blends. From the present investigation, P20B30 fuel is found to give optimum engine performance and emission characteristics.ThesisItem Open Access Theoretical and experimental analysis of CI engine fuelled with Calophyllum inophyllum biodiesel and diesel with ethanol as an additive(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Gautam, Puneet Singh; Gupta, V.K.Energy is a basic contribution for social and economic development. The energy strategy of a nation goes for productivity and security and to give access which being environment friendly and accomplishment of primary resources for energy generation. Petroleum fuels will keep on playing a predominant part in the area of energy in our country in couple of few decades. However, traditional or petroleum fuel resources are limited, non-renewable, polluting and, accordingly, should be utilized judiciously whereas renewable energy sources are indigenous, non-polluting and its availability is unlimited. In this way, their utilization ought to be supported in every possible way. The aim of this present work is to extract biodiesel from a new non edible oil known as calophyllum inophyllum (tamanu oil). The retained finished biodiesel is further blended with the reference baseline fuel i.e. diesel and ethanol in proposed percentage and to test the performance parameters such as brake power, brake specific fuel consumption, brake thermal efficiency, and emission characteristics (exhaust temperature, smoke density) experimentally on 4.4kW rated power, single cylinder four stroke compressed ignition engine. Then few of the experimental results are validated using two zone, zero dimensional model after discretizing empirical correlations with forward difference method and solving the same in matrix laboratory (MATLAB) and some other important theoretical results such as bulk in-cylinder pressure, in-cylinder temperature, heat release rate, power, torque, work done etc. at different loads are analysed.ThesisItem Open Access Experimental investigations on a double pass solar air heater having broken arc shaped ribs combined with staggered ribs(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Joshi, Sumit; Varshney, LokeshThe efficiency of smooth solar air heaters is low due to low heat transfer coefficient of air. The reason for low convective heat transfer coefficient is due to presence of laminar sub layer. Efforts for enhancing heat transfer have been directed towards artificially destroying this boundary layer. The use of artificial roughness in the form of wires and integral ribs on absorber plate of solar air heaters have been used to create turbulence near the heat transferring surface and break laminar sub layer. Double pass solar air heater (DPSAH) with artificial roughness is an approach to further improve the thermal performance of a conventional SAH. Experimental study is done on a DPSAH with ‘broken arc shaped ribs combined with staggered ribs’ as a artificial roughness on lower side of absorber plate for improving the thermo hydraulic performance of the collector. The study has been carried out for Reynolds number (Re) from 3000 to 12000, relative gap position (bꞌ/b) from 0.3 to 0.9 and relative roughness pitch (p/e) from 10 to 14. Other parameters like relative roughness height (e/D) of 0.0354, arc angle (α) of 30˚ and relative staggered rib size (r/e) of 2.5 are kept constant. It is concluded from the experimental results that the value of thermohydraulic performance parameter is higher for ‘broken arc shaped ribs combined with staggered ribs’ as compared to that for a continuous arc ribs. It is found that thermohydraulic performance parameter is highest in case of relative gap position of (bꞌ/b) as 0.6 and relative roughness pitch (p/e) as 10 which ranges from 2.09 to 2.46 for a Reynolds number of 3000 to 12000 respectively. Enhancement in thermo hydraulic performance parameter is estimated to be 33% higher for ‘broken arc shaped ribs combined with staggered ribs’ as compared with continuous arc shape roughness.ThesisItem Open Access Process intensification studies in a fixed bed heat regenerator(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Singh, Siddhartha Kumar; Murthy, D.S.Fixed bed regenerators are the heat exchangers used for transferring heat from hot fluid to cold fluid using solids as intermittent storage medium. The thesis presents the 3D, CFD modelling and analysis of unsteady flow through a fixed-bed regenerator. To account for the detailed flow complexities in porous media commercial Ansys Fluent 14.0 software was used. The predicted results of the temperature profiles were compared with the previous experimental results and a good agreement found between them. In order to carry out intensification of the process of heat transfer in the fixed bed heat regenerator, inlet boundary of the fixed bed heat regenerator was moved thereby simulating moving bed regenerator. Thus, moving bed heat regenerator is simulated without actually moving the solids of the bed. Temperature profiles along bed length and for different planes of regenerator bed are drawn with superficial air velocity of 0.382m/s, for both the fixed and moving bed regenerator. It is observed that by moving the inlet boundary of the fixed bed regenerator temperature difference between the hot effluent gas and cold solids of the regenerator in the heat transfer zone increases resulting in faster heating of the bed. Pressure drop across the regenerator also decreases by moving the inlet boundary. It is observed that bed is heated up to a maximum inlet temperature of 400 °C in 102 minutes while in case of fixed bed it 123 minutes. Thus, the bed heats up 17 % faster in case of moving bed for the flow velocity of 0.382m/s.ThesisItem Open Access Study the performance and emission characteristics of CI engine running on different blends of biodiesel from waste cooking oil with diesel(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Pancholi, Bhawana; Gupta, V.K.ThesisItem Open Access Modelling and buckling analysis of thin plate composite sections(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Singh, Vishal; Saxena, RakeshIn the present work, modelling and buckling analysis of thin plate composite sections has been performed. The buckling study of laminated composite thin plate is performed at two different levels i.e. analysis of lamina to compute its properties and buckling analysis of laminated composite thin plate with various parametric values. In analysis of lamina, relations from previous literature results have been used to determine elastic properties of boron-epoxy, glass-epoxy and jute-epoxy lamina. In analysis of lamina, previous literature relations were incorporated with MATLAB to determine properties of lamina for different values of fiber volume fractions. The buckling analysis have been done with laminated composite thin plate under uniaxial compressive loading. The computational results have been validated with analytical results. We have observed, maximum error in computational and analytical methods is 6.03%. In present buckling study, buckling load of laminated composite thin plate has been computed for various parameters i.e. such as fiber volume fraction (V), ply orientation angle (θ), aspect ratio, thickness ratio, boundary loading conditions and geometry of cut-out with different composite materials. From the results, it has been found that buckling load increases linearly with fiber volume fraction whereas minimum buckling load is observed for ply orientation angle from 15 to 30 degree. The buckling load increases with increase in aspect ratio whereas it decreases with increase in thickness ratio. The buckling analysis has also been done with different boundary conditions and cut-out geometry which are required for various applications.