International Journal of Thermal Technologies
Deprecated: preg_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated in /home/u414331547/domains/ijtt.info/public_html/cache/t_compile/6f0e36d0d3bf4065b2ef80f2b18331528665552d^c940d5f8376e6af774deb7e0a5efe41e5bfff906_0.plugins-1-plugins-generic-webFeed-generic-webFeed.rss.tpl.php on line 50
Effects of the combustor size and the molecular diffusion on a methane air premixed microflame stability
In this research work the effects of the cylindrical combustor size and the molecular diffusion on a methane air premixed microflame stability are investigated in order to highlight the parameters that most influence the given stability of the flame during microcombustion. A premixed methaneous–air microflame has been through a simulation-modelisation method was established as in a microreactor with a cylindrical configuration. Variable external diameters have been tested with a fixed thickness e = 200 μm and a length L = 10000 μm. The input dimensions of the micro-reactor considered are 2000 μm, 1000 μm, 500μm, 300μm and 200 μm. The results showed that the molecular diffusion coefficient influences the position, the formation and the shape of the flame along the micro reactor unpreviously. Indeed, when the inlet diameter of the reactants is reduced, the flame is shapely deflected from the inlet of the microreactor towards the inside of the reactor with a more bamboo appearance allowing a certain more or less intensive temperature redistribution along the micro-reactor walls. Nevertheless, the order of magnitude of the temperature does not suffer from any influence because of the stability of the coefficient of the molecular diffusion.
Micro reactor, microcombustion, molecular diffusion, combustion Size, flame stability.
Consideration of Differential Thermal Expansion Rates during Stress Analysis of Cladded Pipes
The application of Corrosion resistance alloy (CRA) cladded pipes has become more customary across the Industry in recent years for high corrosive services (e.g. Sour gas). These pipes serve as a replacement not only to carbon steel pipes (Having high potential to corrosion over a period of time) but also as a replacement to expensive Alloy Steel / Stainless Steel pipes. CRA cladding technology involves application of a metallurgical junction on carbon steel pipes with an inner coating of high corrosion resistance alloy material (e.g. SS316, Alloy 625). This paper’s is intended to study the stress generated in the piping on account of differential thermal expansion Coefficients considering bimetallic approach while satisfying the ASME B 31.3 code requirements per para 301.7.3. Further results obtained are compared using analytical and finite element models.
Corrosion resistance alloy (CRA), Clad, Abaqus
A contribution to a numerical characterization of the thermal transfers in a saw tooth solar collector
In this study, we have developed and modeled a saw tooth solar collector. It is a solar collector with single pass between the transparent cover and the absorber fixed on the insulator. The cover is double glasses with the plane upper glass and the lower glass in the shape from saw teeth. The absorber is also in the shape of saw tooth. After having chosen the mathematical models describing the thermal behavior of the prototype, the equations governing the transfers in the solar collector were based on the analogy between heat transfer and electric transfer. The algebraic systems of equations deduced from a discretization of these equations by an implicit method to finite differences are solved by Gauss algorithm. The theoretical characterization was compared with that experimental particularly for the collector outlet temperature and the absorber temperature. The analysis of the temperature profiles showed that at midday sun for an air velocity of 0.3 m/s, the temperature of the air at collector outlet for a theoretical characterization reaches 79.19 °C whereas that of the practical characterization is only 77.7 °C thus guaranteeing a total output of 22.15 %, and 22 % respectively for the theoretical characterization and the experimental when characterization sunshine is maximum. The results obtained by the models compared, concerning, show that calculations resulting from this study result closer to those from the undertaken experiments.
Solar collector, convection coefficient, saw tooth, thermal transfer, numerical characterization.
Suppression of the Horizontal Temperature Gradient on the Drying Tray in an Artisanal Firewood Dryer
Analyses on many artisanal firewood fish dryers have permitted to say that the operators have good experiencebased processing skills, but loss due to some fish calcination during the process, or other poorly dried, has always been a deep concern amongst the producers. This has been investigated throughout literatures too where few works have been done to acquire an isotherm on the drying surface. By upgrading a selected dryer with an intermediate layer of iron sheet between fire and fish, plus an opening on the back wall of the burning chamber, we successfully achieved an isothermal drying surface which is one prerequisite for standardization of the overall drying process.
Firewood fish dryer, Temperature control, Heat distribution, Isothermal surface, standardization
Experimental Investigation on Performance and Emission characteristics of DI Diesel Engine using Canola oil as Bio-diesel fuel
Experiments are carried out to study performance and emission characteristics of a diesel engine fuelled with diesel fuel, a Canola Biodiesel and its blends 10% by volume(BD10),20%(BD20),30%(BD30),40%(BD40),50%(BD50) and 100%(BD100).Tests have been conducted on four stroke, single cylinder, vertical, water cooled, cold start, compression ignition high speed diesel engine with different loading conditions at a constant speed of 1500 rpm. The results are presented in the form of Brake specific fuel consumption, mechanical efficiency, brake thermal efficiency and emission characteristics of CO, CO2, UHC and NOx. From the results it is observed that BD10, BD20, BD100 biodiesel blends given better Brake specific fuel consumption, mechanical efficiency, brake thermal efficiency than pure diesel. HC, CO, CO2 emissions are lower for BD10 and BD20 blends and NOxemissions are lower for BD100 except at 20% load. Also HC, CO2, NOxemissions are lower for pure biodiesel (BD100) compared to pure diesel and a reverse behavior is observed with respect to CO emissions. The results revealed that the Canola biodiesel showed comparable performance and can be a good replacement to diesel fuel.
Biodiesel, Canola oil, Blending, DI diesel engine, Performance, Emissions.
Numerical analysis of fluid flow and heat transfer in single tube fin arrangement of an automotive radiator
This paper deals with CFD analysis of the fluid flow and the heat transfer of the automobile radiator. Normally existing radiator has multi tube fin arrangement. In those tubes a spring is inserted to delay the flow of the fluid thus it transfers more amount of heat. In this arrangement the water from the engine flow through these tubes and get cooled. Here the heat transfer takes place only the peripheral surface which is contact with the fins only. To increase the heat transfer rate the multi tube of the radiator arrangement is replaced by a single plate tube with wire mesh arrangement. Wire mesh arrangement is used to delay the fluid flow thereby increasing the heat transfer rate. The heat transfer of the existing radiator is 20.57W and the proposed design has 77.13W where the heat transfer rate is increased by 3.74 times.
Radiator, Multi tube, Single tube, Heat transfer, Convection
Economic feasibility of an inverter and conventional air conditioners for residential buildings in Iraq
The use of air conditioners has become a necessity recently in the Republic of Iraq due to the very hot weather of Iraq and the inability of citizens to withstand high temperatures in the summer. This led to an increase in the annual electricity bill, hence the aim of this study is to study the economic feasibility of air conditioners supported by the technology of the inverter and its importance in energy saving. This research presents economic analysis to investigate the Payback period (PP) and net present value (NPV) between a conventional air conditioner and inverter type air conditioner. The selected air conditioners used in this study are from 1800 BTU inverter and non-inverter type spilt unit, residential air conditioner. The mathematical model of economic analysis is developed based on proposed model developed by previous researches. The economic analysis showed that the increase in the percentage of energy saving and the daily operating hours reduces the Payback period in the case of the use of air conditioner supported by an Inverter technology compared to a traditional air conditioner. It is found that an inverter type air conditioner with highest operating time of 15 hours per day has shortest PP of only (3 year), and the net present value(NPV=+900,221.05 IQD ) and internal rate of return (IRR=55%) .
Economic feasibility, payback period, inverter air conditioner, conventional air conditioner, net present value (NPV).
Theoretical prediction of performance of Single and Double pass solar air heaters with artificial roughened absorber plates
Investigations are carried out on artificial roughened absorber plates on Solar air heater. The roughness parameters are identified in to five basic profiles A, B, C, D and E. The profiles A, B and C are basic cubical and cylindrical profiles and the profiles D and E are categorized as rod arrangement of inline and staggered nature. Both frictional and heat transfer characteristics have been studied. Optimum results of frictional and heat transfer characteristics have been arrived out. Results show a higher value of frictional factor for the profile E. All reasons of variations have been justified and discussed. The deviation of friction factor from modified Balsius equation is within the limit of 4.32 %. Results also show higher value of Nusselt number for the inline rod arrangement of SAH than the other profiles .
Roughened absorber plates, Solar air heater, Nusselt number, Friction factor
Combustion and Emission Characteristics of Hydrous Ethanol– Gasoline Blends with Co-solvents in Spark-ignited Single cylinder Engine
In Brazil, hydrous ethanol is blended with gasoline and is successfully implemented in flexi fuel engines and it has the potential to directly compete with fossil fuels. However, the Ethanol Blending Program of India has not been successful due to non-availability of sugarcane molasses and could not achieve its 5% blending target based on the literature review study. Hydrous ethanol with co-solvent is proposed in this work as a promising blending oxidant instead of energy-intensive anhydrous ethanol in gasoline. This research work also delves into the challenges of using hydrous ethanol in gasoline blended fuel such as water tolerance, fuel properties, and fuel selection. The selected fuel sample 2EW30TBA10, which contains 30% hydrous ethanol and 10% TBA (t-butyl alcohol), and gasoline was selected based on water tolerance of the blended sample and stability. The combustion and emission characteristics of the selected fuel sample 2EW30TBA10 are studied in 4-stroke, single cylinder, water cooled engine, and the performances are compared to base fuel (E0) and reference fuel (E10). The significant contributions of the present research work are the development of combustion model using MATLAB using: Apparent heat release model (Model1) and Combustion pressure method (Model-2) and the results are validated using modified Wiebe function. There was an increase in brake thermal efficiency by 5% compared to base fuel (E0) and the specific fuel consumption (sfc) for 2EW30TBA10 fuel sample is 290 g/KWh as compared to E10, which is 300 g/KWh and for Petrol (E0), sfc is 360 g/KWh. There was a reduction in CO and HC emission compared to base fuel (E0) and an increase in NOx emissions. The cyclic variations of experimental results are validated using a non-linear regression model.
Combustion, Emission, Hydrous Ethanol, Ethanol-Gasoline, Co-solvents, Combustion modelling, Ethanol Blending Program
Decreasing CPU Time in Simulation of Thermal Recoveries in Hydrocarbon Reservoirs
The work flow of reservoir studies is an integration of interdisciplinary works by the geophysicists, reservoir geologists, petro physicists and reservoir engineers. Reservoir simulation helps to determine initiation of operating controls at the proper time, and to consider all important economic factors. Future improvement in oil recovery with pressure maintenance by re-injection of produced gas or by water injection into an aquifer can also be evaluated. The original fine grids are generated by primary geological blocks which are output of geological software. The upscaling is necessary since geological software by means of statistical methods create models with millions and even billion of grid blocks and dynamic simulation on these models is practically not possible. In this paper we are going to introduce a fast simulation method in high heterogeneous multiphase reservoir which steam injection simulated as a thermal enhanced oil recovery. The principle of multi scale grid generation of this method is base on the trend of streamline which could be as a great map to find effective segments of a reservoir. The simulation results on the geological structure well compared with the results of upscaled models. The results confirm that this method consumes less run time with nearly accuracy of fine model.
Steam Injection, Geological Model, Run Time, CPU Time, Elapsed Time
umerical Evaluation of Pollutants Emissions in a Homogeneous Methane/Air Micro Flame
Exhausting pollutant gas in a plug flow micro reactor are identified, described and predicted in this paper. For this, a premixed methane/air micro flame was simulated by a simplified chemical kinetics mechanism with four equations of Jones and Lindstedt. In addition to the Jones and Lindstedt model, one chemical kinetic mechanism with three equations describing the formation of thermal NO was integrated in Comsol 4.2a code, all that equations describing the production process and disappearance of the major chemical species. Simulations in stoichiometric and lean conditions with equivalent ratio ф equal to 0.9 and 0.7 show that the simulations with Jones and Lindstedt model provide a stable flame with the temperatures of the same order as that obtained with a detailed chemical kinetic mechanism as reported in the literature. Production of carbon dioxide (CO2) varies with the richness of the mixture. It is high with ф = 1 and in the order of 250 ppm, this value remains smaller than the required threshold for breathable air. Carbon monoxide (CO) is not found in the products of combustion due to the high temperatures at the outlet of the microreactor in the three cases.
Micro reactor, microcombustion, simplified chemical kinetic, pollutant emissions, equivalent ratio
Modelling and transient simulation of a regenerative open Joule cycle reciprocating Ericsson engine for micro-CHP applications
The open Joule cycle reciprocating Ericsson engine shows promising results as regards small-scale cogeneration applications using renewable energies such as biomass or solar energy. Integrating a regenerative heat exchanger into a simple open Joule cycle helps to improve the engine performance thanks to the recovery of the waste heat of hot gases downstream the expander. A dynamic model of a small open Joule cycle Ericsson engine with a shell-andtube counter-flow regenerative heat exchanger is developed and simulated in order to study the operation stability, the system behaviour especially during transient phases, and the control strategies. Compared to the engine configuration without regeneration, simulation results predict a slower hot start-up transient followed by a stable operation of the engine with 21% increase of the engine thermal efficiency, 14.3% increase of the engine power output and a 529.5K exhaust air flow suitable for cogeneration purposes. Subjected to a selected perturbation (10kPa compressor inlet pressure drop) the engine reacts well and the operation is stabilized after a much longer transient phase. Valve settings are also addressed to maintain the system set pressure.
Joule cycle reciprocating engine, recuperator, modelling, transient simulation, micro-CHP
Investigation on Performance and Emission Characteristics of Low Heat Rejection Diesel Engine using Alternate Fuels
Petroleum based fuels play a vital role in rapid depletion of conventional energy sources along with increasing demand and also major contributors of air pollutants. Major contributors of today’s energy demand in India is being met with fossil fuels hence it is high time that alternative fuels for engines should be derived from indigenous sources .The enormous growth of world population, increased technical development and standard of living in industrial nations has led to this intricate situation in the field of energy, supply and demand. As India is agricultural country there is wide scope for the production of vegetable oils (both edible & non edible oils) from different oil seeds. The present work is focused only on non-edible oils as fuels for engines, as the edible oils are in great demand and far too expensive. All neat oils are to be collected and converted into their respective methyl esters through transesterification process. Thermal barrier coatings are becoming increasingly important in providing thermal insulation for heat engine components. Thermal insulation reduces in-cylinder heat transfer from the engine combustion chamber as well as reducing component structural temperatures. Likewise, Bio-diesel too has a potential as a promising alternative fuel to their diesel counterparts while being renewable, sustainable, and environmental friendly. In this work, the comparative effect of performance and emission characteristics of a standard compression ignition engine (STD) with Magnesium stabilized Zirconia (MSZ) coated (LHR) engines are investigated. Fuel-related properties have to be calculated and analyzed with those of conventional diesel engine. The effect of use of bio-diesel fuel on engine power, fuel consumption and thermal efficiency has to be calculated and analysed with that of conventional diesel engine.
Magnesium Stabilized Zirconia (MSZ), Bio-Diesel, Animal Tallow Methyl Ester, Low Heat Rejection Engines.
Investigation on the Tensile Strength of the Friction Stir Welded similar joint of Al/Al alloy using high thermal diffusivity backing plate material
Friction Stir Welding process is a novel green solid state joining process for soft materials such as aluminium alloys. The weld quality is governed by the proper selection of parameters such as forge force rotational speed of the tool, welding speed, backing plate material etc. Thermal boundary condition at the bottom of the work piece plays an important role for obtaining the sound joint. The backing plate material governs these thermal conditions. In this case study, high thermal diffusivity backing plate material which consisted of AA2099 was used for joining of the plates of Structural Aluminium alloy. It was observed that the tensile strength was improved.
Friction Stir Welding; Magnesium alloy; Backing plate; Tensile Strength
Experimental Investigation of Drag Reduction with polymer of Kerosene flow in a horizontal pipe
flow, where adding certain amount of drag reducing agent, such as polymer. From addition of that agent, it causes a dramatic frictional drag reduction. This work shows the effect of the pressure drop on a drag reduction along pipe in a horizontal placing with kerosene flow is investigated. The tested fluid was kerosene and poly isobutylene polymer (PIB) with 50 ppm (part per million), 75 ppm, and 100 ppm weight concentration of polymer: Experimental investigation gives more description of this phenomenon. The experimental results illustrate that pressure drop and pressure gradient decreases with increasing of polymer concentration and volume flow rate. The friction factor decreases with increasing of additive concentration and velocity. The drag reduction percentage increases with increasing the mean velocity, polymer concentration and temperature. The experimental results show that maximum drag reduction (DR %) about 19%.
Kerosene flows, polymer, pressure drop, drag reduction
Performance Analysis of Solar Air Heater using CFD Simulation
Solar energy has emerged as one of the alternate to conventional sources of energy. Solar air heaters are one of the important devices to utilize solar energy. But, poor heat transfer coefficient is one of the major problem in solar air heater. In this research article, an attempt is made to increase heat transfer coefficient of solar air heater by putting Hollow bodies over the absorber plate. These resulted in increase in heat transfer coefficient, efficiency and increase in outlet temperature of air simultaneously.
Solar Air Heater, Heat Transfer Coefficient, Efficiency, CFD Simulation.
Experimental Investigation on Performance, Combustion Characteristics of Diesel Engine by using Sunflower Oil
Biodiesel with fuel additives has been gaining increased attention from engine researchers in view of the energy crisis and increasing environmental problems. The present work is aimed at experimental investigation on bio diesel is the Sunflower oil which is obtained from the seeds by using the transesterification process. In the initial stage tests are to be conducted on the four stroke single cylinder direct ignition diesel engine and base line data is generated. Further in second stage the test was conducted on the same engine at same operating parameters by using the diesel blended with the sunflower oil esters with different blending ratios such as S10, S20, S30 and the performance parameters (Brake Thermal Efficiency, Brake Specific Fuel Consumption) and also emission parameters (CO, HC, NOx, CO2, unused oxygen and smoke density) are evaluated. Among all the blends S30 has shown the better performance in the parameters and also in the emissions. So S30 is taken as the optimum blend. Finally the performance and emission parameters obtained by the above test are compared with the base line data obtained earlier by using diesel.
Combustion characteristics, sunflower oil, Diesel-Biodiesel blends, Transesterification process, performance, emissions
Examination of Thermal Performance for Solar Air Heater with Modified Absorber
Everyday sun delivers enormous amount of energy towards earth. Solar energy received by earth in a day is equal to total energy consumed by us in whole year. Plenty of research has been done in utilizing solar energy efficiently. Solar air heater is always a hot topic between the researchers. Different configurations of absorber plate with roughness has been prepared and tested to increase efficiency. In this article, a Computational Fluid Dynamic analysis of solar air heater having triangular shaped bodies place over the absorber plate had been performed. Enhancement in the performance of solar air heater is resulted.
Copyright (c) 2018 International Journal of Thermal Technologies
Effective numerical model for flow boiling of a nanofluid
Flow boiling of Al2O3-Water nanofluid has been investigated numerically using the Eulerian multiphase model in ANSYS FLUENT. The physical properties have been computed using the two phase mixture model. In the Eulerian multiphase model, Rensselaer Polytechnic Initiative (RPI) nucleate boiling model has been used for modeling boiling. Axial vapor fraction has been computed in case of flow boiling of water and heat transfer coefficient has been computed in case of flow boiling of Al2O3-Water nanofluid. The numerical results obtained were in good agreement with experimental results. The RPI model predicts the heat transfer characteristics quickly.
Nanofluid, Flow boiling, RPI modeling, FLUENT
Effect of rib height on heat transfer and friction factor in a square channel roughened by inclined ribs with a gap
This work concentrates on experimental investigation of forced convection heat transfer and friction factor (pressure drop) characteristics of a rib-roughened surface with varying rib height of discrete inclined ribs. The test section of the square duct (AR=1) is roughened on its top and bottom wall with Inclined square ribs having a gap on its length. Reynolds number (Re) based on duct hydraulic diameter varied from 5,000 to 40,000, relative roughness pitch (p/e) is 10, relative gap width (g/e) is 1 and relative gap position (d/W) is taken as 1/3. The rib attack angle (α) is taken as 600 .The effects of five rib height to hydraulic diameter ratios (e/Dh) of 0.047, 0.060, 0.074, 0.087 and 0.10 on heat transfer in terms of Nusselt number and friction loss in the form of friction factor are experimentally investigated. The results show that there is significant effect on the Nusselt number and friction factor when (e/Dh) has changed. It is observed that the heat transfer augmentation in the channel increase with decrease in the rib height to hydraulic diameter ratio (e/Dh) (from 0.10 to 0.060) but only at the cost of the pressure drop across the test section. Maximum heat transfer enhancement is associated with ribs of (e/Dh) = 0.060 which also produces the maximum pressure drop penalty in the range of parameters investigated. The thermal hydraulic performance for all (e/Dh) ratios is also presented. The thermal hydraulic performance of ribs with (e/Dh) = 0.060 has found maximum and is about 2.18.
Nusselt number, Friction factor, Rib height to hydraulic diameter ratio, Reynold’s number, thermal performance
Experimental Analysis of Hybrid Earth Air Tunnel Heat Exchanger in Series Connection Coupled with Water Cooled Heat Exchanger Installed at Bikaner
EATHE is a system which maintains surroundings temperature comfortable to human body and has no bad impact on environment of earth like other air-conditioning system i.e. works on VCRC which uses CFCs as refrigerant i.e. causes global warming and ozone layer depletion. In this research paper, Thermal Performance of Simple EATHE is developed by introducing new concept i.e. Hybrid EATHE in Series Connection Coupled with Water Cooled Heat Exchanger in which outlet air temperature of Simple EATHE is further decreased by using wastage water of water cooler i.e. flowing inside the Water Cooled Heat Exchanger which is coupled at outlet of EATHE in Series Connection. The setup of system is installed at Mechanical Engineering Department Government Engineering College Bikaner. Experimental Analysis was carried out on the system in the month of September. The Minimum, Average & Maximum Air Temperature Diff c respectively.
EATHE, Summer Cooling, Series Connection, Hybrid System, Heat Exchanger, Thermal Performance.
Performance and Analysis of Two Stroke Dual and Triple Spark plug Single Cylinder SI Engine with Gasoline fuel
In two stroke spark ignition engines due to some losses there is high exhaust emissions and low brake thermal efficiency and some time it will be occur because of incomplete combustion, which has an effect on the engine as a high load in operating condition. By improving some parameters we can improve the engine’s efficiency i.e. specific fuel consumption rate and Thermal Efficiency of the engine. This performance is achieved by using dual spark plug in two stroke gasoline also its effect on the engine parameter is analyzed. For experiment a spark-ignition engine was used to study the effects of spark plug location on a four spark plug SI engine performance. Constructed simulation can be used for either single- or four-spark plug configuration. Here we consider arrangement that the plug is located center of the head. To make a comparison, property of single spark plug were also considered on different spark plug locations.
1-Twin spark plug and Tri spark plug, 2- S.I engine, 3- Combustion chamber
CFD Analysis of Waste Heat Boiler Duct for Maximum and Even Flow Distribution of Hot Gases
Waste heat boiler power plants are widely used throughout the world for recovering waste heat from sources like exhausts gases of gas turbines, heat generated during some process in a plant or heat absorbed by cooling fluid from high temperature equipment etc. The duct which is the object of study was a part of waste heat boiler of a working power plant. Cracks, pits and overheating of duct casing was observed after some time of service of this duct. The theoretical studies as well as simulation with the help of available CFD software have been carried out in this work for finding the root cause and its solution. Commercially available computational fluid dynamics (CFD) software ANSYS-FLUENT15.0 is used for numerical simulation of duct. Results of simulation revealed that duct design was creating swirl inside the duct and flow of gases was unevenly distributed inside it. Un even distribution of flow of hot gases was the main reason of uneven distribution of heat which caused overheating and failure of duct. The solution is to get maximum and even flow distribution of hot gases inside the duct .Duct model was modified by modeling guide plate sin side its two inlets i.e. GT(gas turbine) inlet and RA (regenerative air) inlet in different numbers, configurations and angles to get distributed flow of hot gases inside the duct.
Waste heat boiler (WHB), Gas turbine (GT), Steam turbine (ST), Computational fluid dynamics (CFD), Swirl, Flow distribution.
Effect on Performance and Emission Characteristics of C.I Engine by Preheating of Intake Air Using Heat Wheel
The air pollution is one of the major problems I’m now days throughout the world. The main causes of air pollution are exhaust products of automobiles and industries. Exposure to air pollution can lead to respiratory and cardiovascular diseases, which is estimated to be the cause for 6.2 lakhs early deaths in 2010. To control air pollution from the automobiles, the Indian government implement some emission standards i.e. BSES. Bharat stage emission standards (BSES) are emission standards instituted by the Government of India to regulate the output of the air pollutants from the Internal Combustion Engines. The standards based on European regulations were first introduced in 2000. Progressively stringent norms have been rolled out since then. Up to March 2017 the automobiles are run under the Bharat stage 3 (BS-3). After then Bharat stage 4 (BS-4) were implemented by the Government of India. BS3 emits are more pollutants (CO, HC, CO2 etc.) to the Environment then BS-4. That is the main reason behind banning the BS-3. In my thesis, I focused on how to control the emission levels as per the BS-4. Heat wheel is a rotary air to air heat exchanger. It comprises porous wire mesh as a matrix material and electric motor for driving wheel. The effect of preheated air on standard diesel fuel engine indicate a good result in performance of engine and on emission control. Higher intake air temperature increases Brake Thermal efficiency and decreases the specific fuel consumption. Easy vaporization and better mixing of air and fuel occur due to warm up of inlet air, which causes lower CO emissions. Better Combustion is occurred due to preheating of intake air, which also causes lower engine noise. The experiment was carried out at different loads (No load, half load, and Full load) at engine speed of 1500 rev/min on single cylinder 4 -stroke variable compression ratio engine. A Test was applied in which the working fuel as pure diesel and blend of diesel and kerosene (90% diesel and 10% kerosene) and results were analyzed. From the results, I observed that by preheating of intake air, emissions are reduced in both the conditions of fuel as pure diesel and blend of diesel and kerosene.
CI Engines, Emission Control, BSES standards, Pre heating, blended fuels.
Experimental Investigations on Exhaust Emissions with Low Heat Rejection Diesel Engine with Crude Vegetable Oil with Magnetic Induction
In the scenario of fast depletion of fossil fuels and increase of pollution levels the search for alternative fuels has become pertinent. Particulate emissions and oxides of nitrogen are exhaust emissions from diesel engine cause health hazards once they are inhaled in. They also cause environmental impact. Hence control of these pollutants is an immediate task and urgent. Crude vegetable oils are important substitutes for diesel fuel, as they are renewable, and have comparable properties with diesel fuel. However, drawbacks associated with crude vegetable oil of high viscosity and low volatility which cause combustion problems, call for low heat rejection (LHR) engine with its significant characteristics of maximum heat release and ability to handle the low calorific value fuel. LHR engine consisted of ceramic coated cylinder head. A hydrocarbon fuel was polarized by exposure to external force such as magnetism. Exhaust emissions of particulate emissions and oxides of nitrogen (NOx) were determined at full load operation with conventional engine (CE) and LHR engine with and without magnetic induction with vegetable oil operation. LHR engine with crude vegetable oil operation with magnetic induction improved exhaust emissions when compared with CE with vegetable oil operation.
Alternative fuels, Vegetable oil, Low heat rejection, Exhaust emissions
Performance Improvement of Window Air Conditioner by using Bottle Neck Arrangement
In present scenario human comfort is the main criteria. For that purpose many Air conditioners are introduced in the market like window AC, split AC and central AC. Not only for human purpose it is become an essential need for Industrial purpose for both small scale and large scale industries. For common household purposes maximum we use Window AC. But during actual use it is not possible to evaluate the performance of an AC with all the parameters like coefficient of performance and cooling effect. Since these are the main parameters for an air conditioner. Without these calculations it is also not possible to know the factors that affecting on the performance of an air conditioner. So in this thesis main concentration is on investigation on performance parameters of air conditioner, for this purpose window AC test rig is prepared. By using this test rig easy to find out the Actual COP. By adding Bottle Neck Arrangement, in order to improve the performance of air conditioner without any extra amount by using of this simple arrangement, with this theses we save the power improve the cooling effect of wind air conditioner especially in summer user can feel more comfort with this type of air conditioner.
Air Conditioner, COP, Performance Improvement, Bottle Neck set up.
Comparison of combustion characteristics of Petcoke and Indian sub bituminous coal in a CFB Test facility
Fluidized Bed Combustion (FBC) is one of the best suited combustion technologies for petcoke combustion owing to its capability of handling fuels with low volatile and high sulphur content. In this study, petcoke and Indian sub bituminous coal (coal from Singareni mines, Telengana, India) are fired separately in Circulating Fluidized Bed (CFB) test facility and its combustion characteristics are studied and compared. Even though petcoke is a low reactive fuel compared to Indian coal, temperature profile shows petcoke has a stable combustion. Significant post combustion in cyclone is noticed while combusting petcoke. Around 40-60o C rise in the cyclone temperature is noted during combustion of petcoke compared to 20-30o C while burning sub bituminous coal. Compared to Indian sub bituminous coal petcoke has high sulphur content (4-9 %) and low ash content, therefore it requires limestone addition for in situ sulphur capture and for maintaining bed inventory. Owing to the limestone addition, petcoke firing shows a better material distribution among the splash zone. Although CFB boilers are fuel flexible, and petcoke can be fired in CFB boilers designed for Indian coals, test results show that combustion efficiency of petcoke is lower than that of Indian coal. Combustion efficiency can be improved by certain design modifications such as higher furnace height, higher cyclone efficiency and higher refractory zone. The present study explore the opportunities of using 100% petcoke in CFB boiler.
Petcoke combustion, Indian coal, CFB, Cyclone post combustion, Combustion efficiency
Dual Source Solar Powered Combined-Cycle Multi-Temperature Refrigeration System for Cold Production in the Context of Off-Grid and Rural Energy Access
It is proposed and analyzed the coupling of a dual source solar PV & T with a combined compression/ejection multitemperature refrigeration cycle intended for the simultaneous production of cold for refrigeration and freezing, in the context of off-grid and rural energy access. The developed simulation model helped to perform the system performances for environment friendly refrigerants R290, R152a and R134a. It is shown that for a 1.5 kW domestic fridge-freezer applications, using the developed system should require surface area PV panels and 3.1 m2 surface areas solar collector; while equipping a 15kW multi-temperature cold room with this system leads to 44 m2 surface area PV panels and 31 m2 surface area solar collector. In addition to the effect of the incident solar irradiance, the influence of the ambient temperature on system performance was also analyzed when using a flatplate solar collector
: Combined-cycle refrigeration system, multi-temperature, solar PV & T, coefficient of performance, off-grid and rural energy access
Integral Method for Flat Non-Isothermal Turbulent Jet
In the current work has developed an integrated solution on a flat vertical turbulent two-phase non-isothermal flow. It represents a model of ascending convective flow over the fire, which also brings smoke and combustion products.
Integral method; vertical, turbulent, two-phase
Efficiency Improvement, Emission Control & Energy Saving in NGCC Power Plant by using Advanced Solar Techniques
fficiency Improvement, Emission Control and Energy Saving i.e. Fuel Consumption (EEE) these three factors are play a very key role in every power generation Industries but as per the Surveys majority of industries world over are still failure to achieve these factors at a time once the industries are really ignore these factors, future generation face a lot of problem so theses mainly concentrate on this area to saving this EEE at a time with some endless natural resources i.e. solar energy. A solar thermal assisted NGCC power plant was developed to investigate the impact on plant efficiency, output and CO2 emission with addition of solar thermal energy. An exemplary NGCC power plant was selected as Base Case of this study it is a Saudi Electricity Company PP12 Combined Cycle Power Project. Here I conducted an audit to know about the efficiency of power plant and identify, where the losses located and reasons for that & Find the end solutions to that problem. The power plant capacity is 2050.9 MW. In this Model a solar thermal energy input of 26 MW to the Heat Recovery Steam Generation (HRSG), the duct firing should be shut off, up to 2350 kg/h natural gas would be saved and 6.5 t/hr. CO2 emission would be eliminated. However, there would also be some loss in power from combined cycle i.e. approximately 4.08 MW. Another solar input approach shows 14.30 MW additional electricity would be generated with 42 MW solar thermal addition. The thermodynamic analyses in this theses demonstrated the possibilities to utilize the solar thermal energy to reduce fuel consumption and CO2 emission at the same time to increase the efficiency of a NGCC power plant.
NGCC Power Plant, Solar Assisted, Efficiency Improvement, Emission Control, Energy Saving