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Technical Paper

Investigations on NOx and Smoke Emissions Reduction Potential through Diesel-Water Emulsion and Water Fumigation in a Small Bore Diesel Engine

2020-10-30
2020-32-2312
In the present work, a relative comparison of addition of water to diesel through emulsion and fumigation methods is explored for reducing oxides of nitrogen (NOx) and smoke emissions in a production small bore diesel engine. The water to diesel ratio was kept the same in both the methods at a lower concentration of 3% by mass to avoid any adverse effects on the engine system components. The experiments were conducted at a rated engine speed of 1500 rpm under varying load conditions. A stable water-diesel emulsion was prepared using a combination of equal proportions (1:1 by volume) of Span 80 and Tween 80. The mixture of Span 80 in diesel and Tween 80 in water was homogenized using an IKA Ultra Turrax homogenizer with tip stator diameter 18mm at 5000 rpm for 2 minutes. The water-in-diesel emulsions thus formulated were kinetically stable and appeared translucent. No phase separation was observed on storage for approximately 105 days.
Technical Paper

Free Multibody Cosimulation Based Prototyping of Motorcycle Rider Assistance Systems

2020-10-30
2020-32-2306
Due to the increasing computational power, significant progress has been made over the past decades when it comes to CAD, multibody and simulation software. The application of this software allows to develop products from scratch, or to investigate the static and dynamic behavior of multibody models with remarkable precision. In order to keep the development costs low for highly sophisticated products, more precisely motorcycle rider assistance systems, it is necessary to focus extensively on the virtual prototyping using different software tools. In general, the interconnection of different tools is rather difficult, especially when considering the coupling of a detailed multibody model with a simulation software like MATLAB Simulink. The aim of this paper is to demonstrate the performance of a motorcycle rider assistance algorithm using a cosimulation approach between the free multibody software called FreeDyn and Simulink based on a sophisticated multibody motorcycle model.
Technical Paper

Wall Heat Flux on Impinging Diesel Spray Flame: Effect of Hole Size and Rail Pressure under Similar Injection Rate Condition

2020-10-30
2020-32-2313
The fuel economy of recent small size DI diesel engines has become more and more efficient. However, heat loss is still one of the major factors contributing to a substantial amount of energy loss in engines. In order to a full understanding of the heat loss mechanism from combustion gas to cylinder wall, the effect of hole size and rail pressure under similar injection rate conditions on transient heat flux to the wall were investigated. Using a constant volume vessel with a fixed impingement wall, the study measured the surface heat flux of the wall at the locations of spray flame impingement using three thin-film thermocouple heat-flux sensors. The results showed that the characteristic of local heat flux and soot distribution was almost similar by controlling similar injection rate except for the small nozzle hole size with increasing injection pressure.
Technical Paper

Development of Friction Materials Regulations for Four Latin American Countries

2020-10-05
2020-01-1615
Brakes are the most important safety device in a vehicle, however there are few barriers to manufacture, import, or sell friction materials in most of the countries, including USA. European countries, with the ECE R90 program, are a big exception. International Transport Forum published in 2016 the “Benchmarking of road safety in Latin America” report, it mentions that worldwide 17.5 people in every 100,000 die in road accidents, however Andean countries mortality rate is 23.4 and South American 21.0, considerably higher than the worldwide average.
Technical Paper

Comparison of Particulate Matter and Number Emissions from a Floating and a Fixed Caliper Brake System of the Same Lining Formulation

2020-10-05
2020-01-1633
The particulate emissions of two brake systems where characterized in a dilution tunnel optimized for PM10 measurements. The larger of them employed a fixed caliper (FXC) and the smaller one a floating caliper (FLC). Both used ECE brake pads of the same lining formulation. Measured properties included gravimetric PM2.5 and PM10, Particle Number (PN) concentrations of both untreated and thermally treated (according to exhaust number regulation) particles using Condensation Particle Counters (CPCs) having 23 and 10 nm cut-off sizes, and an Optical Particle Sizer (OPS). The brakes were tested over a novel test cycle developed from the database of the Worldwide harmonized Light-Duty vehicles Test Procedure (WLTP). A series of WLTP tests were performed starting from unconditioned pads, to characterize the evolution of emissions until their stabilization. Selected tests were also performed over a short version of the Los Angeles City Cycle.
Technical Paper

Novel Modelling Techniques of the Evolution of the Brake Friction in Disc Brakes for Automotive Applications

2020-10-05
2020-01-1621
The aim of the presented research is to propose and benchmark two brake models, namely the novel dynamic ILVO model and a neural network based regression. These can estimate the evolution of the brake friction between pad and disc under different load conditions, which are typically experienced in vehicle applications. The research also aims improving the knowledge of the underlying mechanism related to the evolution of the BLFC (boundary layer friction coefficient), the reliability of virtual environment simulations to speed up the product development time and reducing the amount of vehicle test in later phases and finally improving brake control functions. With the support of extensive brake dynamometer testing, the proposed models are benchmarked against State-of-the-Art. Both approaches are parametrised to render the friction coefficient dynamics with respect to the same input parameters.
Technical Paper

Enclosure-In-Chamber Setup to Achieve Near-Zero Background Concentrations for Brake Emissions Testing

2020-10-05
2020-01-1634
Measuring brake emission is still a challenging non-standardized task. Extensive research is ongoing. Updates of work in progress are presented at SAE Brake Colloquium and PMP meetings. However, open items include how to achieve lower background concentration and how to design the brake enclosure. A low background concentration is essential as brake events are short and some emit in the range of reported background levels. Hence these emissions are difficult to distinguished from the background level. Even more critical, a high background concentration can result in a wrong particle number emissions value, either overestimated, background counted as emissions, or underestimated, background level subtracted, and low emission events no longer detected and counted. However, reducing the background level to less than 100 #/cm³ appeared to be quite challenging.
Technical Paper

A Priori Analysis of Acoustic Source Terms from Large-Eddy Simulation in Turbulent Pipe Flow

2020-09-30
2020-01-1518
The absence of combustion engine noise pushes increasingly attention to the sound generation from other, even much weaker, sources in the acoustic design of electric vehicles. The present work focusses on the numerical computation of flow induced noise, typically emerging in components of flow guiding devices in electro-mobile applications. The method of Large-Eddy Simulation (LES) represents a powerful technique for capturing most part of the turbulent fluctuating motion, which qualifies this approach as a highly reliable candidate for providing a sufficiently accurate level of description of the flow induced generation of sound. Considering the generic test configuration of turbulent pipe flow, the present study investigates in particular the scope and the limits of incompressible Large-Eddy Simulation in predicting the evolution of turbulent sound sources to be supplied as source terms into the acoustic analogy of Lighthill.
Technical Paper

Engine Sound Reduction and Enhancement Using Engine Vibration

2020-09-30
2020-01-1537
Over the past decade, there have been many efforts to generate engine sound inside the cabin either in reducing way or in enhancing way. To reduce the engine noise, the passive way, such as sound absorption or sound insulation, was widely used but it has a limitation on its reduction performance. In recent days, with the development of signal processing technology, ANC (Active Noise Control) is been used to reduce the engine noise inside the cabin. On the other hand, technologies such as ASD (Active Sound Design) and ESG (Engine Sound Generator) have been used to generate the engine sound inside the vehicle. In the last ISNVH, Hyundai Motor Company newly introduced ESEV (Engine Sound by Engine Vibration) technology. This paper describes the ESEV Plus Minus that uses engine vibration to not only enhance the certain engine order components but reduce the other components at the same time. Consequently, this technology would produce a much more diverse engine sound.
Technical Paper

Extended Solution of a Trimmed Vehicle Finite Element Model in the Mid-Frequency Range

2020-09-30
2020-01-1549
The acoustic trim components play an essential role in Noise, Vibration and Harshness (NVH) behavior by reducing both the structure borne and airborne noise transmission while participating to the absorption inside the car and the damping of the structure. Over the past years, the interest for numerical solutions to predict the noise including trim effects in mid-frequency range has grown, leading to the development of dedicated CAE tools. Finite Element (FE) models are an established method to analyze NVH problems. FE analysis is a robust and versatile approach that can be used for a large number of applications, like noise prediction inside and outside the vehicle due to different sources or pass-by noise simulation. Typically, results feature high quality correlations. However, future challenges, such as electric motorized vehicles, with changes of the motor noise spectrum, will require an extension of the existing approaches.
Technical Paper

A Generic Testbody for Low-Frequency Aeroacoustic Buffeting

2020-09-30
2020-01-1515
Raising demands towards lightweight design paired with a loss of originally predominant engine noise pose significant challenges for NVH engineers in the automotive industry. From an aeroacoustic point of view, low frequency buffeting ranks among the most frequently encountered issues. The phenomenon typically arises due to structural transmission of aerodynamic wall pressure fluctuations and/or, as indicated in this work, through rear vent excitation. A possible workflow to simulate structure-excited buffeting contains a strongly coupled vibro-acoustic model for structure and interior cavity excited by a spatial pressure distribution obtained from a CFD simulation. In the case of rear vent buffeting no validated workflow has been published yet. While approaches have been made to simulate the problem for a real-car geometry such attempts suffer from tremendous computation costs, meshing effort and lack of flexibility.
Technical Paper

Experimental Investigation on the Effects of Cooled Low Pressure EGR and Water Injection on Combustion of a Turbocharged GDI Engine

2020-09-27
2020-24-0003
This work focuses on the effects of cooled Low Pressure EGR and Water Injection observed by conducting experimental tests consisting mainly of Spark Advance sweeps at different cooled LP-EGR and WI rates. The implications on combustion and main engine performance indexes are then analysed and modelled with a control-oriented approach, showing that combustion duration and phase and exhaust gas temperature are the main affected parameters. Results show that cooled LP-EGR and WI have similar effects, being the associated combustion speed decrease the main cause of exhaust gas temperature reduction. Experimental data is used to identify control-oriented polynomial models able to capture the effects of LP-EGR and WI on both these aspects. The limitations of LP-EGR are also explored, identifying maximum compressor volumetric flow and combustion stability as the main ones.
Technical Paper

An Active Safety System Able to Counter Aquaplaning, Integrated with Sensorized Tires, ADAS and 5G Technology for both Human-Driven and Autonomous Vehicles

2020-09-27
2020-24-0019
Autonomous vehicles must guarantee safety in all road conditions, including driving on wet roads. Aquaplaning (or hydroplaning) is a phenomenon known since the beginning of automotive history, never solved by an active safety system. Currently, no countermeasure system on the market is able to effectively counteract aquaplaning: ABS, ESP or TCS are still inefficient in overcoming this situation. Latest statistical data confirm that the higher percentage of accidents, injuries and deaths are caused by wet road conditions. The aquaplaning happens when the water on the road is too much and the tires start to float causing the instantaneous loss of control. Such phenomenon occurs in human-driven vehicles, with the responsibility of the driver, but in autonomous vehicles (e.g. Level 5), the responsibility for the safety depends on the car and the reduction of the speed is not a solution.
Technical Paper

Modeling and Simulation of a Fighter Aircraft Cabin Temperature Control System Using AMESim

2020-09-25
2020-28-0497
Environmental Control System (ECS) of an aircraft is a complex system which operates classically in an air standard refrigeration cycle. ECS controls the temperature, pressure and flow of supply air to the cockpit, cabin or occupied compartments. The air cycle system of ECS takes engine bleed air as input. Parameters like bleed air pressure and temperature, mass flow, the external factors like ambient temperature, pressure, and aircraft attitude affect the performance of ECS to a large extent especially during transient. So, it is very important to consider the transient characteristics of these parameters in the design stage itself in order to ascertain the dynamic response of the system. This paper explains in detail the importance of transient input characteristics during the detailed design of ECS. A typical temperature control scheme for combat aircraft ECS has been studied and modeled in LMS AMESim.
Technical Paper

Modular Design and Analyze of Air Intake Manifold for Formula Vehicle

2020-09-25
2020-28-0485
The SAE formula student car organization constrained a rule to place a restrictor of diameter 20mm in between the throttle body and the engine inlet. The restrictor is a component that reduces and regulates the mass flow of air into the engine inlet. For this, a venture nozzle will be used as a restrictor in a vehicle to decrease the air pressure and increase the velocity in the intake manifold. Our proposed work aims to minimize the pressure drop by changing the convergent and divergent angles in the restrictor. For this by using solidworks eight various combinations of models with convergent angle as 13, 15 degrees, and divergent angle as 5,7 degrees was designed and analyzed using CFD fluent in ansys work bench. In this, 13 degree as convergent and 5 degree as a divergent model was found to have laminar airflow throughout with optimum pressure drop. The plenum is a large duct that equalizes the pressure drop caused by the restrictor in order to improve the efficiency of the engine.
Technical Paper

Ergonomic Study of Occupant Seating Using Near-Vertical Posture for Shared Mobility Applications

2020-09-25
2020-28-0519
Transportation system is at the brink of revolution and many new ways of mobility are arising in the market to ease the pressure on the established transportation infrastructure. Many companies and governments around the world are exploring innovative options in the space of shared mobility to reduce the overall carbon footprint. To expedite the adoption of shared mobility in India, it is necessary to make such options comfortable and cost-effective. One of the most effective way to make shared mobility options cost effective is to comfortably increase occupancy per vehicle footprint. This paper aims to evaluate a novel method of occupant seating to identify the maximum number of passengers a vehicle can accommodate without significant impact on occupant comfort. It is assumed that shared mobility options are used for a short duration of commute, and hence the comfort of the seat can be marginally compromised to increase the total number of occupants.
Technical Paper

Influence of Injection Parameters on Performance and Emission of DI Diesel Engine Fuelled by 1,4-Dioxane Emulsified Fuel

2020-09-25
2020-28-0518
The pattern of utilizing the water/diesel emulsion fuels in engines had been given great importance due to its ecological and exhaustion of petroleum reserves. This investigation displays the impact of 1,4-dioxane emulsified fuel on performance and emissions at various operating pressures. 1,4-dioxane emulsified fuel (DWSD10) was prepared with 10% 1,4-dioxane, 10% water, 0.2% surfactant and 79.8% diesel. To estimate the engine performance and emissions, the engine was operated with 180 bar, 200 bar and 220 bar operating pressures and the output was equated with diesel fuel operating on normal pressure of 200 bar. BTE of 1,4-dioxane emulsified fuel at 220 bar was higher when compare with diesel fuel. CO, HC and BSEC were lower at 220 bar on par with diesel fuel. However, NOx was increases for the higher operating pressure. Overall, except NOx, at higher injection pressure (@220 bar) the 1,4-dioxane emulsified fuel outperforms the diesel fuel in terms of emission and performance.
Technical Paper

Investigations on the Effect of Synchronizer Strut Detent Groove Profile on Static and Dynamic Gear Shift Quality of a Manual Transmission

2020-09-25
2020-28-0319
Automotive manufacturers are constantly working towards enhancing the driving experience of the customers. In this context, improving the static and dynamic gear shift quality plays a major role in ensuring a pleasant and comfortable driving experience. Moreover, the gear shift quality of any manual transmission is mainly defined by the design of the synchronizer system. The synchronizer sleeve strut detent groove profile plays a vital role in defining the performance of the synchronizer system by generating the minimum required pre-synchronization force. This force is important to move the outer synchronizer ring (blocker ring) to the required index position and to wipe-out the oil from the conical friction surfaces to build rapid high cone torque. Both these functional requirements are extremely critical to have a smooth and quick synchronization of the rotating parts under dynamic shift conditions.
Technical Paper

Experimental and Numerical Investigation of Contact Pressure Existence in Sealing Structure

2020-09-25
2020-28-0343
Sealing is one of the important components in the automotive and aerospace industry. The primary function of the lip seal is to protect contamination and retaining the lubricant. This investigation relates to a study of contact pressure existence on sealing structure between there mating region. Sealing for steering intermediate shaft should sustain sliding motion between shaft and seal as well as protection of lubricant from contamination and retention. Contact pressure analysis of Steering intermediate shaft with hyper elastic rubber seal is done at static condition using ABAQUS. Experiments were also conducted to check contact pressure between seal and shaft by using Fuji-pressure film sensor. The result from CAE analysis was compared with experimental data with 75% of the correlation with respect to CAE. This analysis of contact pressure helps to support on giving enough interference between seal and shaft which satisfies the need of sealing for an intermediate shaft.
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