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Applied Fluid Mechanics - Volume:10 Issue: 5, Sep-Oct 2017

Journal Of Applied Fluid Mechanics
Volume:10 Issue: 5, Sep-Oct 2017

  • Special Issue
  • تاریخ انتشار: 1396/07/17
  • تعداد عناوین: 11
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  • M. Muruganandam *, P. C. Mukesh Kumar Pages 1-5
    The exciting coolants have reached their limitations of heat dissipating capacity. It is studied from the literature review that nanofluids are the novel and alternate heat transfer medium with significant temperature-dependent thermal conductivity even at very low particle concentrations than the conventional heat transfer fluids. In this experimental investigation, the multi walled carbon nanotube (MWCNT) water is used as a coolant in four stroke single cylinder diesel engine to assess the performance of the engine. The MWCNT/ water nanofluid is prepared with surfactant to get the stable suspension of nanofluid. Tests are performed by constant the mass flow rate 330 LPH of coolant nanofluids and by changing the load and by keeping the speed constant. It is found that the brake thermal efficiency increases by 10 to 15%, exhaust temperature decreases by 8 to 10% decreases and the specific fuel consumption decreases when compared to water as a coolant at the same testing condition.
    Keywords: Nanofluid, Thermal conductivity, Coolant, Mass flow, Brake thermal efficiency
  • K. Palanisamy *, P. C. Mukesh Kumar Pages 7-13
    In this investigation, the heat transfer and pressure drop analysis of a cone helically coiled tube heat exchanger handling MWCNT( Multi Walled Carbon nanotube)/water nanofluid have been carried out experimentally. The MWCNT/water nanofluids of 0.1%, 0.3%,and 0.5% particle volume concentration have been synthesized with the addition of surfactant Sodium dodecylbenzene solfonates by using two step method and characterized. The test runs conducted laminar flow in the Dean number range of 481
    Keywords: MWCNT-water, Cone helically coiled tube, Nusselt number, Thermal conductivity, Secondary flow, Volume concentration
  • A. Parthiban *, S. Sathish, M. Chandrasekaran Pages 15-22
    Abrasive water jet cutting is a advanced manufacturing process to be used cut various type of material economically. The width of AWJC or kerf width is affected by Abrasive flow rate, cutting speed and stand of distance as well as the work-piece material. In this present work AWJC of stainless steel AISI 316L 2mm thickness has been investigated. Design of experiment was implemented by to applying the full factorial design method. In this work to relate the top kerf width and bottom kerf width and the above process parameters. Mathematical models were developed to evaluate the relationship between the process parameters and the top and bottom kerf width. Also, process parameters effects on the edge quality have been defined. Finally, the numerical optimization has been used to found the optimal AWJC conditions at which the highest edge quality like top and bottom kerf width can be achieved.
    Keywords: Water Jet Cutting, Full factorial design, Stainless Steel, Optimization
  • S. K. Lakshmanaprabu *, A. V. Nasir, U. Sabura Banu Pages 23-32
    The mathematical model for two interacting conical frustum tank level (TICFTL) process is proposed. The control of TICFTL process is difficult due to the nonlinearity, interaction effect between input flow and output level of tanks. Hence, the nonlinear process is linearised around proper operating points. Then, the decentralized PI, centralized PI, centralized FOPI controllers are designed and then the control parameters are tuned using genetic algorithm. The closed loop controller performances are simulated and compared in terms of settling time, rise time and integral error criteria. It is found that centralized PI controller has better servo and regulatory response than the decentralized PI, centralized FOPI controller. The liquid inflow rates are optimally manipulated by the centralized PI controller to track the set point variation and to reject the disturbance effectively than centralized FOPI, decentralized PI controller.
    Keywords: Two interacting conical frustum tank level process, Flow control, Level control, Centralized PI, FOPI, Decentralized PI controller
  • R. Srinivasan *, V. Vijayan, K. Sridhar Pages 33-39
    This paper elucidates the outcomes of an experimental study validating a methodology for applying aerodynamic coefficients for a missile with grid fins. A grid fin is an unconventional lifting and control surface that consists of an outer frame supporting an inner grid of interesting planar surfaces of small chord. As a part of the experimentation, determinations were made based on the calculations at a match number of 0.2 and angle of attack 10o for a missile with grid fins. The simulations were found to be efficacious as well as probable in determining the flow structure around the fin in the separated-flow region at the higher angles of attack. This was impeccably apparent in the successful calculation of nonlinear behavior viscous computational fluid dynamic simulations to calculate the flow field and for that fin, which indicated negative normal force at the higher angle of attack. The modeling of unconventional grid fin missile is done in CAD software named catia V5. The enmeshing of geometry is accomplished in a pre-processor named Gambit. In addition to that, the solving and the post processing are experimented in a solver called Fluent.
    Keywords: Horizontal stabilizer, Pitch, Lift, Induced drag, Angle of attack
  • T. Sathish* Pages 41-50
    This paper presents an important analysis on the fuel extracted from waste plastic using the process of pyrolysis. Here, the plastics collected from local municipality are used for conversion of solid plastic waste to liquid fuel. The fuel prepared is blended with mixtures of oxygenated compounds to test the performance of the fuel. The bio-diesel or waste plastic oil (WPO) from the waste solid plastic is tested with other blended mixtures to find the mechanical efficiency, emission rate, brake test efficiency and total fuel consumption. Here, the efficiency between the pure diesel mixture and WPO with different blends that varied between 10-50% of pure diesel oil is tested. The performance of the produced WPO-diesel blended oil performs with better efficiency than the other fuels.
    Keywords: IC engine, Plastic oil, Brake test, Pyrolysis
  • P. C. Mukesh Kumar *, M. Muruganandam Pages 51-59
    The technological development for industries faces the challenges in meeting out the cooling demand due to the existing coolants have reached their limitations. The nanofluids are the dispersion of the nanomaterials into base fluids have been developed to solve the problems associated with the existing coolants in the thermal systems. The stability of nanofluids is a crucial issue for both scientific research and practical applications to provide better cooling. In this investigation, seven Multi walled Carbon Nano Tube MWCNT nanofluids have been prepared by using two step method with Distilled water, Coolant oil, Engine oil, Gear oil, Vegetable oil, Coconut oil, and Grown oil as base fluids at the volume concentration of 0.1% and without adding any stabilizing agent. The UV-Vis spectrophotometers, measure of pH values, and photograph capturing techniques have been used for stability analysis in this investigation by keeping the nanofluids under static condition period of 30 days. It is found from the three stability analysis techniques that the stability of nanofluids are in the increasing order of MWCNT / Distilled water nanofluid, MWCNT / Coolant oil nanofluid, MWCNT / Coconut oil nanofluid, MWCNT / Vegetable oil nanofluid, MWCNT / Engine oil nanofluid, MWCNT /Gear oil nanofluid and MWCNT/Grown oil nanofluid. The MWCNT / Distilled water nanofluid has poor stability and MWCNT/Grown oil nanofluid has good stability.
    Keywords: Nanofluids, Base fluids, Stability, MWCNT, Sonication
  • V. Sivakumar *, K. Visagavel, A. Selvakumar Pages 61-68
    On this era of increasing energy demand, natural ventilation appears to be the proper solution as it provides the necessary ventilation required for the room by means of the natural forces, such as wind. It ensures salubrity and pleasant indoor climate through least possible energy consumption at least possible cost. Our project aims to identify the air velocities and air change per hour in a cross ventilated room through numerical predictions. The standards for natural ventilation are taken into account along with the heat transfer concepts and the analysis is carried out on different shapes of inlets and outlets at different heights. The models were analyzed using CFD software by using SIMPLE and SIMPLEC algorithm to solve the equations and the results are compared.
    Keywords: Ventilation, Aperture shaped window, Computational fluid dynamics, Less energy consumption
  • G. Balaji *, S. Nadaraja Pillai, C. Senthil Kumar Pages 69-77
    Circular cylindrical towers which are sporadically seen in engineering structures such as buildings, towers, etc are basically considered as bluff body. The flow around the circular cylindrical structures gained interest among the researchers. Since there has been lot of development in infrastructure, transport, telecommunication in the last two decades. Such cylindrical towers invite more attention, since the failure of circular cylindrical tower/ structures is not only due to the surface pressure distribution but also due to the effect of wake induced by the flow separations. Even though there are engineering challenges in circular cylindrical structures, different designs of structures such as stepped cylinders, rough cylinder and taper cylinder etc. are used in various applications. The flow field downstream is relatively less explored for the tapered circular cylinder than other cylinders. Effects of downstream wake due to such cylindrical structures are not only affecting other structures downstream but also induce vibration on itself. In this paper, circular cylinders of various taper ratios are considered for the study at various sub critical Reynolds number. Extensive wind tunnel studies were performed on various taper ratios ranging from 0.6 to 1 in the increment of 0.1 for various x/D and h/D locations using hot wire anemometer. Various parameters like wake width, dissipation length, wind speed ratios were measured downstream for various taper ratios. The result shows that the magnitude of wake width gradually increases with increase in downstream distance along with increase in taper ratio whereas dissipation length and wind speed ratio increases with decrease in taper ratio.
    Keywords: Wind speed ratio, Dissipation length, Wake width, Velocity deficit, Tower wake
  • M. Vijayakumar *, P. C. Mukesh Kumar Pages 79-84
    An experimental investigation is conducted to evaluate the effects of using blends of 1-Butanol, n-Propanol and biodiesel with base diesel fuel, with 5% and 10% (by vol.) each alcohol fuel (1-Butanol and n-Propanol), on the diesel engine performance and exhaust gas emissions. The experimental investigation of the above fuel blends, with the engine working at different loads. Engine performance and exhaust gas emissions such as nitrogen oxides, carbon monoxide, carbon dioxide, unburned hydrocarbons and smokiness are measured. The measured results of alcohol fuel blends with different concentration compared with base diesel fuel results. It is revealed that this fuel, which can be produced from alcohol fuel blend with biodiesel and base diesel blends, is very promising biodiesel performance enhancement of diesel engine operations. The present work proved that the 5% of alcohol fuel blend with 25% of biodiesel and diesel produced maximum efficiency and minimize the exhaust emission level compare with 10% of alcohol blend and base diesel.
    Keywords: Diesel engine, 1-Butanol, N-Propanol, Emission, Performance
  • P. Lakshmanan*, P. Kaliyappan, M. Ranjithkumar, K. Aravinth, D. Vakkachan, C. Moorthy, S. Kumar Pages 85-91
    The importance of biodiesel as a renewable and economically available alternative to fossil fuel for applications in Compression Ignition (CI) engines has led to intense research in the field over the last two decades. This is predominantly due to the depletion of petroleum resources and increasing awareness of environmental and health impacts from the combustion of fossil fuel. Biodiesel is favored over other biofuels because of its compatibility with present day CI engines, with no further adjustments required to the core engine. Such as carbon monoxide, Sulphur oxides, unburnt hydrocarbons and particulate matters are potentially reduced. The effects of biodiesel on nitrogen oxides emission require further tests and validations. The improvement in most of the diesel emission species comes with a trade-off in a reduction of brake power and an increase in fuel consumption. The outcomes completely corroborate the assumption which claims that adding biodiesel to conventional diesel fuel has a strong influence on lowering CO2, CO, HC, Oxides of Nitrogen and smoke.
    Keywords: Compression Ignition engine, Carbon dioxide, Carbon monoxide, Hydrocarbon