Faculty Publications

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    Effect of denatured spirit-water blends on engine performance and exhaust emissions
    (Combustion Institute, 2009) Ashok Babu, T.P.A.; Hubballi, P.A.
    The obj ective of this study was to investigate the effect of using Denatured spirit (DNS = [Ethanol 93.3% + water 6.7%]) and DNS-Water blends as fuels in a four cylinder four stroke SI engine. In the process of investigation, the performance tests were conducted on the engine to analyze brake thermal efficiency (BThE), brake power (BP), engine torque and brake specific fuel consumption (BSFC). Exhaust emissions were also investigated for carbon monoxide (CO), hydrocarbons (HC), oxides of nitrogen (NOx) and carbon dioxide (CO2). The results of the experiments revealed that, both DNS and DNS95W5 (DNS 95% + water 5%) as fuels increase BThe, BP, engine torque and BSFC. The CO, HC, NOx and CO2 emissions in the exhaust decreased. The DNS and DNS95W5 as fuels produced the encouraging results in engine performance and reduced exhaust emissions for all the tested speeds and measured performance parameters. © 2009 Combustion Institute. All rights reserved.
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    Experimental analysis of SI engine performance and emission characteristics with gasoline-denatured spirit blends as alternative fuels
    (2010) Hubballi, P.A.; Ashok Babu, T.P.
    The experimental study focused on investigating benefits of unleaded gasoline (P100) - denatured spirit [DNS (ethanol 93.3% v/v + water 6.7% v/v)] blends as fuel in a four cylinder four stroke SI engine. Performance tests were conducted to study volumetric efficiency (VolE), brake thermal efficiency (BThE), brake power (BP), engine torque (torque), brake specific fuel consumption (BSFC). Engine exhaust emissions were investigated for carbon monoxide (CO), hydrocarbons (HC), oxides of nitrogen (NOx) and carbon dioxide (CO2). Experiments were conducted at different engine speeds between 2500 - 4500 rpm maintaining throttle position of 50% throughout the experiments. The fuel blends used include DNS30P70 (ethanol 28 % + water 2% + gasoline 70 %), DNS50P50 (ethanol 46.65 % + water 3.35 % + gasoline 50 %) and DNS85P15 (ethanol 79.3 % + water 5.7 % + gasoline 15 %) which were compared with base fuel P100. The investigations revealed that blending DNS with P100 increases BThE, VolE, BP, torque and BSFC. The CO, HC, NOx and CO2 emissions in the exhaust decrease when compared to P100 operation. The DNS85P15 blend produced encouraging results in improved engine performance and decreased engine exhaust emission.
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    Ultrasonic velocities, densities, and viscosities of glycylglycine and CoCl2 in aqueous and aqueous ethanol systems at different temperatures
    (2010) Santosh, M.S.; Bhat, D.K.; Bhatt, A.S.
    Ultrasonic velocity (u), density (?), and viscosity (?) have been measured for glycylglycine and CoCl2 in aqueous and aqueous ethanol systems at T = (288.15 to 318.15) K. Using the experimental values, the adiabatic compressibility (?s), molar hydration number (nH), apparent molar compressibility (KS?), apparent molar volume (V?), limiting apparent molar compressibility (KS ?{symbol}0), limiting apparent molar volume (V?{symbol}0), their constants (SK, SV), viscosity coefficients of A and B parameters of Jones-Dole equation, relative viscosity (?r), and excess Gibbs free energy of activation (? G* E) were calculated and the results of all these parameters have been discussed in terms of solute-solvent and solute-solute interactions. © 2010 Elsevier Ltd. All rights reserved.
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    Physico-chemical, acoustic and excess properties of glycylglycine-MnCl2 in aqueous ethanol mixtures at different temperatures
    (2010) Santosh, M.S.; Bhatt, A.S.; Bhat, D.K.
    Volumetric, acoustic, refractometric, excess and deviation properties of glycylglycine-MnCl2 in aqueous ethanol mixtures have been reported at T = (288.15 to 318.15) K. Redlich-Kister equation was used to fit the derivate properties. The experimental data of the constituent binaries were analyzed to discuss the nature and strengths of intermolecular interactions. The interdependence of Lf and u has been evolved from Eyring and Kincaid model. The variations in specific acoustic impedance revealed that hydrogen bonding was predominant in the studied binary mixtures. Solvation number indicated structure-breaking tendency of the solute and weakening of local solvent structure. © 2010 Elsevier B.V. All rights reserved.
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    Excess molar volumes, viscosity deviations and isentropic compressibility changes in glycylglycine-NiCl2 aqueous ethanol mixtures
    (2010) Santosh, M.S.; Bhat, D.K.
    The densities, viscosities and ultrasonic velocities for glycylglycine-NiCl2 in aqueous ethanol mixtures have been studied in the temperature range 288.15-318.15K. The excess molar volumes, viscosity deviations and changes in isentropic compressibility for the binary mixtures have been calculated and discussed in terms of hydrogen bonding and structure-breaking effect. The computed results are fitted to the Redlich-Kister polynomial. The results clearly indicate that there is a strong association in the mixtures studied. © 2010 Elsevier B.V.
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    Refractive indices and isentropic compressibilities of glycylglycine- FeCl2 in aqueous ethanol mixtures
    (2010) Santosh, M.S.; Bhat, D.K.
    The density and refractive index studies have been carried out for glycylglycine-FeCl2 in aqueous ethanol mixtures at four different temperatures in the range T = (288.15 to 318.15) K. A comparative study of the refractive indices obtained experimentally and those calculated by means of Gladstone-Dale and Lorentz-Lorenz relation has been made. Among them, the Gladstone-Dale equation afforded similar values to those obtained experimentally. Isentropic compressibilities, -S, and excess molar isentropic compressibilities, KS,mE, were estimated using the Kirkwood model. Using the Redlich-Kister type equations, excess partial molar isentropic compressibilities, KS,iE, were also obtained. The observed negative values of KS,2E in the water-rich region are due to the structural disorderliness. As infinitely dilute water is hydrogen-bonded to ethanol and glycylglycine, the variation of strength of interaction is not sensed by KS,1E,?. © 2010 American Chemical Society.
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    Acoustical and compressibility parameters of glycylglycine-FeCl3 in aqueous ethanol mixture at T = (293.15, 303.15, and 313.15) K
    (2010) Santosh, M.S.; Bhat, D.K.
    Ultrasonic velocity measurement is a reliable procedure that allows quick and easy determination of solvent concentrations in mixtures. This paper presents data of ultrasonic velocities and isentropic compressibilities of (glycylglcyine-FeCl3) in aqueous ethanol mixture at T = (293.15, 303.15, and 313.15) K. Various acoustical parameters were calculated, because of their importance in the study of specific molecular interactions. A less-compressible phase of the fluid and a closer packing of molecules is observed with changes in the intermolecular free length. Quantitative investigation suggests that the mixing of ethanol with an aqueous glycylglycine-FeCl3 solution causes the rupture of hydrogen bonds, with increasing S and Lf values (where the former represents the change in isentropic compressibility and the latter represents the intermolecular free length). Theoretically computed values of isentropic compressibility in the studied mixture using different models indicate the superiority of the very complex procedure. © 2010 American Chemical Society.
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    Spectrophotometric determination of platinum(IV) in alloys, complexes, environmental, and pharmaceutical samples using 4-[N,N-(diethyl)amino] benzaldehyde thiosemicarbazone
    (2010) Naik, P.P.; Karthikeyan, J.; Nityananda Shetty, A.N.
    4-[N,N-(Diethyl)amino] benzaldehyde thiosemicarbazone (DEABT) is proposed as an analytical reagent for the spectrophotometric determination of platinum(IV). The DEABT forms 1:2 yellow complex with Pt(IV), which is sparingly soluble in water and completely soluble in water-ethanol-DMF medium. The Pt(IV)-DEABT complex shows maximum absorbance at 405 nm. Beer's law is valid up to 7.80 ?g cm-3, and optimum concentration range for the determination of platinum(IV) is 0.48-7.02 ?g cm-3. The molar absorptivity and Sandell's sensitivity of the method are found to be 1.755 × 104 dm3 mol-1 cm-1 and 0.0012 ?g cm-2, respectively. The relative error and coefficient of variation (n=6) for the method does not exceed ±0.43% and 0.35%, respectively. Since the method tolerates a number of metal ions commonly associated with platinum, it can be employed for the determination of platinum in environmental samples, pharmaceutical samples, alloys, catalysts, and complexes. The method is rapid as the Pt(IV)-DEABT complex is soluble in water-ethanol-DMF medium and not requiring any time consuming extraction method for the complex. © 2010 Springer Science+Business Media B.V.
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    Performance characteristics of a dual fuel engine operated with Mahua biodiesel and liquefied petroleum gas
    (ASTM International, 2011) Kapilan, N.; Ashok Babu, T.P.; Reddy, R.P.
    Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed the interest of the scientific community to look for alternative fuels of bio-origin such as vegetable oils and ethanol. India is looking at biodiesel derived from Mahua oil (MO), as one of the renewable alternative fuels for compression ignition (CI) engine. Although MO biodiesel (MOB) has several advantages over fossil diesel, in the present scenario, the use of biodiesel is restricted due to its high cost. In India, liquefied petroleum gas (LPG) is easily available and is one of the cheapest gaseous fuels. Hence, use of LPG to fuel a CI engine along with MOB seems to be an option for substitution of fossil diesel. In the present work, LPG, which was fumigated along with the air and biodiesel was admitted into the engine cylinder through conventional fueling device as an igniter. A single cylinder CI engine was modified to work in dual fuel mode and engine tests were carried out at rated speed under variable load conditions. The performance of the engine in dual fuel mode was compared with the diesel. The dual fuel operation results in thermal efficiency close to the diesel and also reduces the NOx and smoke emissions significantly. From the experimental results, we concluded that biodiesel in dual fuel mode with cheaper gaseous fuel induction is an option for reducing the operating cost of the biodiesel fuelled CI engine. Copyright ©2011 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.
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    Performance characteristics of a dual fuel engine operatedwith mahua biodiesel and liquefied petroleum gas
    (2011) Kapilan, N.; Ashok Babu, T.P.A.; Reddy, R.P.
    Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed the interest of the scientific community to look for alternative fuels of bio-origin such as vegetable oils and ethanol. India is looking at biodiesel derived from Mahua oil (MO), as one of the renewable alternative fuels for compression ignition (CI) engine. Although MO biodiesel (MOB) has several advantages over fossil diesel, in the present scenario, the use of biodiesel is restricted due to its high cost. In India, liquefied petroleum gas (LPG) is easily available and is one of the cheapest gaseous fuels. Hence, use of LPG to fuel a CI engine along with MOB seems to be an option for substitution of fossil diesel. In the present work, LPG, which was fumigated along with the air and biodiesel was admitted into the engine cylinder through conventional fueling device as an igniter. A single cylinder CI engine was modified to work in dual fuel mode and engine tests were carried out at rated speed under variable load conditions. The performance of the engine in dual fuel mode was compared with the diesel. The dual fuel operation results in thermal efficiency close to the diesel and also reduces the NOx and smoke emissions significantly. From the experimental results, we concluded that biodiesel in dual fuel mode with cheaper gaseous fuel induction is an option for reducing the operating cost of the biodiesel fuelled CI engine. Copyright © 2011 by ASTM International.