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Technical Paper

Effects of Compression Ratio and Water Vapor Induction on the Achievable Load Limits of a Light Duty Diesel Engine Operated in HCCI Mode

2019-04-02
2019-01-0962
Among the various Low Temperature Combustion (LTC) strategies, Homogeneous Charge Compression Ignition (HCCI) is most promising to achieve near zero oxides of nitrogen (NOx) and particulate matter emissions owing to higher degree of homogeneity and elimination of diffusion phase combustion. However, one of its major limitations include a very narrow operating load range owing to misfire at low loads and knocking at high loads. Implementing HCCI in small light duty air cooled diesel engines pose challenges to eliminate misfire and knocking problems owing to lower power output and air cooled operation, respectively. In the present work, experimental investigations are done in HCCI mode in one such light duty production diesel engine most widely used in agricultural water pumping applications. An external mixture preparation based diesel HCCI is implemented in the test engine by utilizing a high-pressure port fuel injection system, a fuel vaporizer and an air preheater.
Technical Paper

Development of a Standalone Application in MATLAB to Generate Brake Performance Data

2019-04-02
2019-01-0513
Predicting the brake performance and characteristics is a crucial task in the vehicle development activity. Performance prediction is a challenge because of the involvement of various parts in the brake assembly like booster, master cylinder, calipers, disc and drum brakes. Determination of these characteristics through vehicle level tests requires a lot of time and money. This performance prediction is achieved by theoretical calculations involving vehicle dynamics. The final output must satisfy the regulations. This project involves the creation of a standalone application using MATLAB to predict the various brake performances such as: booster characteristics, adhesion curves, deceleration and pedal effort curves, behavior of brakes during brake and booster failed conditions and braking force diagrams based on the given user inputs. Previously, MS Excel and an application developed in the TK Solver environment was used to predict the brake performance curves.
Technical Paper

Parametric Investigations on the Performance of Diesel Oxidation Catalyst in a Light Duty Diesel Engine - An Experimental and Modelling Study

2019-01-09
2019-26-0299
In order to comply with the stringent future emission mandates of automotive diesel engines it is essential to deploy a suitable combination of after treatment devices like diesel oxidation catalyst (DOC), diesel particulate filter (DPF) and DeNox converter (Lean NOx Trap (LNT) or Selective Catalytic reduction (SCR) system). Since arriving at a suitable strategy through experiments will involve deploying a lot of resources, development of well-tuned simulation models that can reduce time and cost is important. In the first phase of this study experiments were conducted on a single cylinder light duty diesel engine fitted with a diesel oxidation catalyst (DOC) at thirteen steady state mode points identified in the NEDC (New European Driving cycle) cycle. Inlet and exit pressures and temperatures, exhaust emission concentrations and catalyst bed temperature were measured. A one dimensional simulation model was developed in the commercial software AVL BOOST.
Technical Paper

Development of a Polymer Electrolyte Membrane Fuel Cell Stack for a Range Extender for Electric Vehicles

2019-01-09
2019-26-0087
Severe air pollution in cities caused largely by vehicular emissions, which requires urgent remedial measures. As automobiles are indispensable modes of personal and public mobility, pre-emptive efforts are necessary to reduce the adverse effects arising from their operation. A significant improvement in air quality can be achieved through large-scale introduction of vehicles with extremely low emission such as hybrid-electric and zero emission vehicles. Range extension of electric vehicles (EVs) is also of utmost importance to alleviate the handicap of restricted mileage of purely plug-in EVs as compared to conventional vehicles. This paper presents development of a polymer electrolyte membrane (PEM) fuel cell stack used for the range extender electric vehicles. The Fuel cell stack for range extender vehicle operated in a dead end mode using hydrogen and air as open cathode.
Technical Paper

Diesel Engine Cylinder Deactivation for Improved System Performance over Transient Real-World Drive Cycles

2018-04-03
2018-01-0880
Effective control of exhaust emissions from modern diesel engines requires the use of aftertreatment systems. Elevated aftertreatment component temperatures are required for engine-out emissions reductions to acceptable tailpipe limits. Maintaining elevated aftertreatment components temperatures is particularly problematic during prolonged low speed, low load operation of the engine (i.e. idle, creep, stop and go traffic), on account of low engine-outlet temperatures during these operating conditions. Conventional techniques to achieve elevated aftertreatment component temperatures include delayed fuel injections and over-squeezing the turbocharger, both of which result in a significant fuel consumption penalty. Cylinder deactivation (CDA) has been studied as a candidate strategy to maintain favorable aftertreatment temperatures, in a fuel efficient manner, via reduced airflow through the engine.
Technical Paper

Effect of Fuel Injector Location and Nozzle-Hole Orientation on Mixture Formation in a GDI Engine: A CFD Analysis

2018-04-03
2018-01-0201
Gasoline direct injection (GDI) engines have gained popularity in the recent times because of lower fuel consumption and exhaust emissions compared to that of the conventional port fuel injection (PFI) engine. But, in these engines, the mixture formation plays an important role which affects combustion, performance and emission characteristics of the engine. The mixture formation, in turn, depends on many factors of which fuel injector location and orientation are most important parameters. Therefore, in this study, an attempt has been made to understand the effect of fuel injector location and nozzle-hole orientation on the mixture formation, performance and emission characteristics of a GDI engine. The mixture stratification inside the combustion chamber is characterized by a parameter called “stratification index” which is based on average equivalence ratio at different zones in the combustion chamber.
Technical Paper

Use of Water-Butanol Blends in a Turbocharged Common Rail Dual Fuel Engine for Enhanced Performance and Reduce Smoke Levels

2018-04-03
2018-01-0251
Experiments were conducted on a turbocharged three cylinder automotive common rail diesel engine with port injection of butanol. This dual fuel engine was run with neat butanol and blends of water and butanol (up to 20% water by mass). Experiments were performed at a constant speed of 1800 rpm and a brake mean effective pressure of 11.8 bar (full load) at varying butanol to diesel energy share values while diesel was either injected as a single pulse or as twin pulses (Main plus Post). Open engine controllers were used for varying the injection parameters of diesel and butanol. Water butanol blends improved the brake thermal efficiency by a small extent because of better combustion phasing as compared to butanol without water. When the butanol to diesel energy share was high, auto-ignition of butanol occurred before the injection of diesel. This lowered the ignition delay of diesel and hence elevated the smoke level.
Technical Paper

Effect of Fuel Injection Parameters on Performance and Emission Characteristics in HCCI Engine - A CFD Study

2017-11-05
2017-32-0096
Today, homogenous charge compression ignition (HCCI) engines are becoming very popular because of their potential to reduce soot and nitric oxides (NOx) emissions simultaneously. But, their performance and emission characteristics are very much dependent upon fuel injection strategy and parameters. However, they also have many challenges viz., improper combustion phasing, high rate of pressure rise and narrow operating range. Therefore, addressing them is very essential before making them a commercial success. This study focuses on evaluating the effect of fuel injection strategy and parameters on the performance and emission characteristics of a HCCI engine by computational fluid dynamics (CFD) analysis. In this study, a four-stroke engine operating in the HCCI mode is considered and the CFD analysis is carried out by using the CONVERGE.
Technical Paper

A Comparison of Different Low Temperature Combustion Strategies in a Small Single Cylinder Diesel Engine under Low Load Conditions

2017-10-08
2017-01-2363
Advanced low temperature combustion (LTC) modes are most promising to reduce green house gas emissions owing to fuel economy benefits apart from simultaneously reducing oxides of nitrogen (NOx) and particulate matter (PM) emissions from diesel engines. Various LTC strategies have been proposed so far and each of these LTC strategies have their own advantages and limitations interms of precise ignition control, achievable load range and higher unburned emissions. In the present work, a small single cylinder diesel engine is initially operated under conventional combustion mode at rated speed, varying load conditions to establish the base line reference data. Then, the engine is modified to operate under different LTC strategies including Homogenous Charge Compression Ignition (HCCI), Premixed Charge Compression Ignition (PCCI) and Reactivity Controlled Compression Ignition (RCCI).
Technical Paper

A Comparison of Conventional and Reactivity Controlled Compression Ignition (RCCI) Combustion Modes in a Small Single Cylinder Air-Cooled Diesel Engine

2017-10-08
2017-01-2365
Reactivity controlled compression ignition (RCCI) is one of the most promising low temperature combustion (LTC) strategies to achieve higher thermal efficiencies along with ultra low oxides of nitrogen (NOx) and particulate matter emissions. Small single cylinder diesel engines of air-cooled type are finding increasing applications in the agriculture pump-set and small utility power generation owing to their lower cost and fuel economy advantages. In the present work, a small single cylinder diesel engine is initially operated under conventional combustion mode at rated speed, varying load conditions to establish the base line reference data. Then, the engine is modified to operate under RCCI combustion mode with a newly designed cylinder head to accommodate a high pressure, fully flexible electronically controlled direct diesel fuel injection system, a low pressure gasoline port fuel injection system and an intake air pre heater.
Technical Paper

Tomographic PIV Evaluation of In-Cylinder Flow Evolution and Effect of Engine Speed

2016-04-05
2016-01-0638
In this study, 3D air-flow-field evolution in a single cylinder optical research engine was determined using tomographic particle imaging velocimetry (TPIV) at different engine speeds. Two directional projections of captured flow-field were pre-processed to reconstruct the 3D flow-field by using the MART (multiplicative algebraic reconstruction technique) algorithm. Ensemble average flow pattern was used to investigate the air-flow behavior inside the combustion chamber during the intake and compression strokes of an engine cycle. In-cylinder air-flow characteristics were significantly affected by the engine speed. Experimental results showed that high velocities generated during the first half of the intake stroke dissipated in later stages of the intake stroke. In-cylinder flow visualization indicated that large part of flow energy dissipated during the intake stroke and energy dissipation was the maximum near the end of the intake stroke.
Technical Paper

Evaluation of Lanthanum Based Diesel Oxidation Catalyst for Emission Reduction with and without Ceria Support

2016-02-01
2016-28-0023
Diesel particulates are mainly composed of elemental carbon (EC) and organic carbon (OC) with traces of metals, sulfates and ash content. Organic fraction of the particulate are considered responsible for its carcinogenic effects. Diesel oxidation catalyst (DOC) is an important after-treatment device for reduction of organic fraction of particulates. In this study, two non-noble metal based DOCs (with different configurations) were prepared and evaluated for their performance. Lanthanum based perovskite (LaMnO3) catalyst was used for the preparation of DOCs. One of the DOC was coated with support material ceria (5%, w/w), while the other was coated without any support material. Prepared DOCs were retrofitted in a four cylinder water cooled diesel engine. Various emission parameters such as particulate mass, particle number-size distribution, regulated and unregulated emissions, EC/OC etc., were measured and compared with the raw exhaust gas emissions from the prepared DOCs.
Technical Paper

In-Cylinder Air-Flow Characteristics Using Tomographic PIV at Different Engine Speeds, Intake Air Temperatures and Intake Valve Deactivation in a Single Cylinder Optical Research Engine

2016-02-01
2016-28-0001
Fuel-air mixing is the main parameter, which affects formation of NOx and PM during CI combustion. Hence better understanding of air-flow characteristics inside the combustion chamber of a diesel engine became very important. In this study, in-cylinder air-flow characteristics of four-valve diesel engine were investigated using time-resolved high-speed tomographic Particle Imaging Velocimetry (PIV). For visualization of air-flow pattern, fine graphite particles were used for flow seeding. To investigate the effect of different operating parameters, experiments were performed at different engine speeds (1200 rpm and 1500 rpm), intake air temperatures (room temperature and 50°C) and intake port configurations (swirl port, tangential port and combined port). Intake air temperature was controlled by a closed loop temperature controller and intake ports were deactivated by using a customized aluminum gasket.
Technical Paper

An Experimental Study of Microscopic Spray Characteristics of a GDI Injector Using Phase Doppler Interferometry

2016-02-01
2016-28-0006
Gasoline Direct Injection (GDI) engine is known for its higher power and higher thermal efficiency. Researchers are steadily determining and resolving the problems of fuel injection in a GDI engine. In order to meet the stringent emission norms such as PM and NOx emitted by a GDI engine, it is necessary to investigate the microscopic spray characteristics and fuel-air mixing process. This paper aims to share the fundamental knowledge of the interacting mixture preparation mechanisms at the wide range of fuel injection pressures. The investigations were carried out at five different fuel injection pressures viz: 40, 80, 120, 160, 200 bar, for 24 mg fuel per injection. A high speed CCD camera was used to determine the macroscopic spray characteristics of the GDI injector. It was found that spray penetration length increased with increasing fuel injection pressure. Phase Doppler Interferometry (PDI) was used to determine the droplet size and droplet velocity for different test fuels.
Technical Paper

Experimental and Numerical Study on Automotive Pleated Air Filters

2016-02-01
2016-28-0100
Nowadays, the automotive engines are downsizing, thus offering limited space for engine intake air filter media. This results in higher aerosol velocity through the filter media. At a higher velocity, the aerosol particles reenter into the fluid stream and thereafter penetrate through the filter media. This causes significant reduction in filtration efficiency. Here, an attempt is made to understand the particle penetration behavior of automotive engine intake air filter media. To establish the flow field, numerical simulations are carried out on a panel type pleated air filter with pleat height 26 mm, pleat pitch 4.5 mm and pleat angle 2.50 degree. A series of tests are conducted using ISO 12103 A2 fine dust on a flat cellulosic paper filter media at a range of velocities derived numerically. The methodology followed for modeling the fibrous media using finite volume commercial CFD code for analyzing the flow field is presented.
Technical Paper

Reducing NO in a Biodiesel Fueled Compression Ignition Engine - An Experimental Study

2015-09-06
2015-24-2483
The replacement of fossil diesel with neat biodiesel in a compression ignition engine has advantage in lowering unburned hydrocarbon, carbon monoxide and smoke emissions. However, the injection advance experienced with biodiesel fuel with respect to diesel injection setting increases oxides of nitrogen emission. In this study, the biodiesel-NO control is attempted using charge and fuel modification strategies with retarded injection timing. The experiments are performed at maximum torque speed and higher loads viz. from 60% up to full load conditions maintaining same power between diesel and biodiesel while retarding the timing of injection by 3 deg. crank angle. The charge and fuel modifications are done by recycling 5% by volume of exhaust gas to the fresh charge and 10% by volume of methanol to Karanja biodiesel.
Technical Paper

Unregulated and Regulated Emissions from Biodiesel Fuelled CRDI SUV Engine

2015-04-14
2015-01-0889
Use of biodiesel from non-edible vegetable oil as an alternative fuel to mineral diesel is attractive economically and environmentally. Diesel engines emit several harmful gaseous emissions and some of them are regulated worldwide, while countless others are not regulated. These unregulated species are associated with severe health hazards. Karanja biodiesel is a popular alternate fuel in South Asia and various governments are considering its large-scale implementation. Therefore it is important to study the possible adverse impact of this new alternate fuel. In this study, unregulated and regulated emissions were measured at varying engine speeds (1500, 2500 and 3500 rpm) for various engine loads (0%, 20%, 40%, 60%, 80% and 100% rated load) using 20% Karanja biodiesel blend (KB20) and diesel in a 4-cylinder 2.2L common rail direct injection (CRDI) sports utility vehicle (SUV) engine.
Technical Paper

Transient Spray Characteristics of Air Assisted Fuel Injection

2015-04-14
2015-01-0920
Gasoline direct injection (GDI) technology is already in use in four wheeler applications owing to the additional benefits in terms of better combustion and fuel economy. The air-assisted in-cylinder injection is the emerging technology for gasoline engines which works with low pressure injection systems unlike gasoline direct injection (GDI) system. GDI systems use high pressure fuel injection, which provides better combustion and reduced fuel consumption. It envisages small droplet size and low penetration rate which will reduce wall wetting and hydrocarbon emissions. This study is concerned with a CFD analysis of an air-assisted injection system to evaluate mixture spray characteristics. For the analysis, the air injector fitted onto a constant volume chamber (CVC) maintained at uniform pressure is considered. The analysis is carried out for various CVC pressures, mixture injection durations and fuel quantities so as to understand the effect on mixture spray characteristics.
Journal Article

Tomographic Particle Image Velocimetry for Flow Analysis in a Single Cylinder Optical Engine

2015-04-14
2015-01-0599
Better understanding of flow phenomena inside the combustion chamber of a diesel engine and accurate measurement of flow parameters is necessary for engine optimization i.e. enhancing power output, fuel economy improvement and emissions control. Airflow structures developed inside the engine combustion chamber significantly influence the air-fuel mixing. In this study, in-cylinder air flow characteristics of a motored, four-valve diesel engine were investigated using time-resolved high-speed Tomographic Particle Imaging Velocimetry (PIV). Single cylinder optical engine provides full optical access of combustion chamber through a transparent cylinder and flat transparent piston top. Experiments were performed in different vertical planes at different engine speeds during the intake and compression stroke under motoring condition. For visualization of air flow pattern, graphite particles were used for flow seeding.
Technical Paper

Effect of Crystallographic Texture on Formability of Some FCC Metals and Alloys

2014-04-28
2014-28-0033
Formability of metals and alloys in general and aluminium alloys and steels in particular is of paramount importance in sheet metal forming in automobile industry. It is well understood that the evolution of preferred crystallographic orientation of crystallites or texture during prior thermo-mechanical processing of sheets plays an important role in determining formability. The formability of sheet is measured in terms of the Lankford parameter or the plastic strain ratio which is defined as the ratio of strain in width direction to that in the thickness direction (R = εw/εt). The variation of Lankford parameter with the rolling direction and standard and ΔR value is widely used in industry as a standard for estimating the formability of the rolled sheets.
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