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Magnesium alloy, known for its high strength and lightweight properties, finds widespread utilization in various technical applications. Aerospace applications, such as fuselages and steering columns, are well-suited for their utilization. These materials are frequently employed in automotive components, such as steering wheels and fuel tank lids, due to their notable corrosion resistance. The performance of magnesium alloy components remains unimproved by normal manufacturing methods due to the inherent characteristics of the material. This work introduces a contemporary approach to fabricating complex geometries through the utilization of Wire-Electro Discharge Machining (WEDM). The material utilized in this study was magnesium alloy. The investigation also considered the input parameters associated with the Wire Electrical Discharge Machining (WEDM) process, specifically the pulse duration and peak current.

Performance of a compression ignition engine fuelled with animal fat and its emulsions as fuel is evaluated. A single cylinder air-cooled, direct injection diesel engine developing a power output of 2.8 kW at 1500 rev/min is used. Base data is generated with standard diesel fuel. Subsequently, animal fat is modified into its emulsions using water and methanol. Comparison is undertaken with diesel, neat animal fat and its emulsion as fuels. Results show improved performance with animal fat emulsions as compared to neat fat. Peak pressure and rate of pressure rise are increased with animal fat emulsions due to improved combustion rate. Heat release pattern shows higher premixed combustion rate with the emulsions. Higher ignition delay and lower combustion duration are found with animal fat emulsions than neat fat. Drastic reduction in black carbon smoke and NO are found with the emulsions as compared to neat animal fat and neat diesel.

The objective of this investigation was to evaluate the effects of a variable intake and exhaust valve timing in terms of opening, closing, opening duration, lift curve and number of active valves per pair on a four cylinder direct-injecting SI engine for the catalyst heating idling phase at the beginning of an NEDC emission test procedure. The first step evaluated the engine behavior at a reference point of operation. Its parameters in valve timing were adjusted to match the valve timing of the base production engine. The second step investigated the effects of an earlier exhaust valve opening while the exhaust valve closing time was kept and the exhaust valve opening duration was extended. The third step was to answer the question for the optimum number of exhaust valves in order to minimize the wall heat losses inside the cylinder head. The optimum 3V exhaust valve timing has been defined as the basis for exhaust valve timing for steps four and five.

The carbon-neutral biodiesel is a promising renewable substitute for fossil diesel that renders the traditional oxides of nitrogen-particulate matter (NOx-PM) trade-off into a unidirectional NOx control problem. Low-temperature combustion (LTC) modes such as homogenous charge compression ignition (HCCI) are attractive for obtaining ultra-low NOx and PM emissions. Studies on utilizing biodiesel fuel for HCCI combustion mode are sparsely available. Moreover, biodiesel emulsions in the HCCI combustion mode have not been attempted so far. Based on this premise, the present work explored the potential to utilize biodiesel and its emulsions having 20% and 25% water by volume under HCCI operating conditions. Biodiesel was prepared from a non-edible Karanja oil. The biodiesel emulsions were prepared using a heated magnetic stirrer apparatus with 3% by volume of the raw Karanja oil as a surfactant.

New energy scenarios for decentralised stationary energy supply based on Liquid Organic Hydrogen Carriers (LOHC) offer an attractive application for hydrogen engines and are a reason why hydrogen engines become topical again. Since hydrogen stored in LOHCs is released under ambient pressure and temperatures of over 200°C, compression and cooling of the hydrogen is needed, lowering the system's overall efficiency. Direct injection of hydrogen is advantageous due to its low volumetric energy density and the tendency towards pre-ignition. The development objective is an injection and combustion strategy for an engine in the performance category below 15 kW and the described fuel supply scenario. Therefore, an one dimensional simulation model of the engine and the hydrogen supplying compressor was built. The simulation results show a large influence of the injection pressure on engine efficiency due to the hydrogen supplying compressor.

Single-cylinder engines in mass production are generally not turbocharged due to the pulsated and intermittent exhaust gas flow into the turbocharger and the phase lag between the intake and exhaust stroke. The present work proposes a novel approach of decoupling the turbine and the compressor and coupling them separately to the engine to address these limitations. An impulse turbine is chosen for this application to extract energy during the pulsated exhaust flow. Commercially available AVL BOOST software was used to estimate the overall engine performance improvement of the proposed novel approach compared to the base naturally aspirated (NA) engine. Two different impulse turbine layouts were analyzed, one without an exhaust plenum and the second layout having an exhaust plenum before the power turbine. The merits and limitations of both layouts are compared in the present study.

Investigations on the suitability of various alcohol fuels as alternatives to conventional diesel fuel were carried out on a passenger car swirl-chamber diesel engine. The test results with a methanol and an ethanol diesel fuel blend show that without alteration of the engine adjustment a good performance behaviour is obtained. In addition to a reduced soot emission and a considerably lower particulate emission the thermal efficiency mainly in the upper load range is higher than with pure diesel operation. The increased HC and CO emissions occuring at low loads can be avoided and a further improvement in energy consumption can be realized by adapting the injection timing for alcohol blend operation. A complete substitution of the diesel fuel with a methanol-ignition improver mixture necessitates an adapted and alcoho-resistent fuel injection system.

Modern automobile applications such as petrol, diesel, and gaseous fuel injection system use dissimilar Inconel 718 (IN718) and Stainless Steel 304 (SS 304) joints. IN 718 is a precipitation-hardened austenitic nickel-based superalloy with exceptional qualities such as high strength, resistance to corrosion, greater toughness, as well as resistance to thermal induced fatigue at elevated temperatures (between 150 and 1500oC), while SS 304 is a T 300 Series austenitic stainless steel alloy that can be used successfully in wide range of applications due to greater resistance to corrosion, good high and low temperature strength and ductility with excellent weld ability and formability. To get a better understanding of the mechanical characteristics of these heterogeneous weldments, these alloy joints were created using laser beam welding, one of the most modern joining techniques for high-strength materials.

Hydrogen engines represent an economic alternative to fuel cells for future energy scenarios based on Liquid Organic Hydrogen Carriers (LOHC). This scenario incorporates LOHCs to store hydrogen from fluctuating renewable energy sources and deliver it to decentralised power generation units. Hydrogen engines were deeply investigated in the past decade and the results show efficiencies similar to CI engines. Due to the low energy density and tendency towards pre-ignition of hydrogen, the key element to reach high efficiency and a safe operation is a direct injection of the hydrogen. Because high injection pressure is not available in practical applications or would reduce the possible driving range, a low injection pressure is favourable. The low density leads to large flow cross sections inside the injector, similar to CNG direct injectors. So far, some research CNG and hydrogen low pressure direct injectors were investigated, but no commercial injector is available.

This study focuses on the phenomenon of lap belt slip on the iliac spines of the pelvis, commonly named “submarining ”. The first objective was to compare the interaction between the pelvis and the lap belt for both dummies and Post Mortem Human Subjects (PMHS). The second objective was to identify parameters influencing the lap belt hooking by the pelvis. For that purpose, a hydraulic test device was developed in order to impose the tension and kinematics of the lap belt such that they mimic what occurs in frontal car crashes. The pelvis was firmly fixed on the frame of this sub-system test-rig, while the belt anchorages were mobile. Fourteen tests on four Post-Mortem Human Subjects (PMHS) and fifteen tests on the THOR NT, Hybrid III 50th and Hybrid III 95th percentile dummies were carried out. The belt tension was kept constant while a dynamic rotation was imposed on the belt anchorages.

This work aims at investigating the effect of oxygen enriched combustion with water injection at the intake on engine’s performance, emission and combustion characteristics of a MO (mahua oil) fueled diesel engine. Initially, experiments were conducted with ND (neat diesel) and neat MO as fuels under variable power output conditions. Subsequently experiments were followed with MO as fuel with different oxygen concentrations such as 21.8%, 22.4%, 23.8% and 24.7% by volume. The optimal oxygen concentration was found based on the engine’s BTE (brake thermal efficiency) as 23.8%. At the optimal oxygen concentration water injection was carried out at 1%, 2%, 3% and 4% by volume. The optimal amount of water injection was obtained as 2%. A comparative study was made for the optimal oxygen concentration and optimal water injection conditions. The maximum BTE was noted as 25.4% and 32.8% with neat MO and ND respectively at the maximum engine power output.

The deposition behavior of brake wear particles on the surface of a wheel and the mechanisms on it have not been fully understood. In addition, the proportion of brake wear particles deposited on the wheel surface compared to the total emitted particles is almost unknown. This information is necessary to evaluate the number- and mass-related emission factors measured on the inertia dynamometer and to compare them with on-road and vehicle-related emission behaviour. The aim of this study is to clarify the deposition behavior of brake particles on the wheel surface. First, the real deposition behaviour is determined in on-road tests. For particle sampling, collection pads are adapted at different positions of a front and rear axle wheel. In addition to a Real Driving Emissions (RDE)-compliant test cycle, tests are performed in urban, rural and motorway sections to evaluate speed-dependent influences.

Use of methanol and ethanol in conventional diesel engines is associated with problems on account of the high self ignition temperature of these fuels. The Hot Surface Ignition (HSI) method wherein a part of the injected fuel is made to touch an electrically heated hot surface for ignition, is an effective way of utilizing these fuels in conventional diesel engines. In the present work two types of HSI engines, one using a large ceramic base and the other using a conventional glowplug were developed. These engines were tested with methanol, M.spirit (about 90 % methanol and 10 % ethanol) and diesel. The results of performance, fuel economy emissions and combustion parameters including heat release rates for these fuels with both the types of HSI engines are presented. Diesel engines are commonly used as primemovers in the mass transportation and agricultural sectors because of their high brake thermal efficiency and reliability.

LNG is a fuel that is under increasing discussion for transport purposes. It differs from CNG because it often has a higher concentration of hydrocarbons > C4. This affects knocking in a negative way. The knocking properties of a gaseous fuel are characterized by the Methane Number (MN) which is defined as the methane content in a mixture of methane and hydrogen which has the same knocking properties as the gas under investigation. It was defined by AVL in the late 1960s. In contrast to the Octane or Cetane Number there is no standardized measurement procedure for the MN, because the equipment AVL used was unique and does not exist anymore. But AVL created a calculation methodology based on the large amount of data they had measured. There are several software implementations of this methodology. Further there are other algorithms which are not based on the AVL data. If an MN is measured on an arbitrary engine the result is called a Service Methane Number (SMN).

In this present investigation, combustion, noise and vibration characteristics were studied in a direct injection compression ignition engine by blending of 20% Pongamia biodiesel with neat diesel. Experiments were conducted with different fuel injection pressures and injection timings. The brake thermal efficiency of the biodiesel blend found increased to 1.75% when the fuel was injected at 200 bar and 23° before top dead center. Higher engine vibration of 5.5% was observed in Y-axis at the fuel injection pressure of 250 bar with the injection timing of 25° bTDC when comparing to the standard operating condition of the engine. The combustion noise level found decreased to 4% when the fuel injection time increased from 21 to 23° bTDC. From Artificial Neural Network analysis, two metrics, such as Coefficient of correlation (R) and Mean Square Error (MSE), were found as 0.99 and 12.6, respectively.

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.

In today's world, there is an increasing emphasis on the responsible use of fiber reinforced materials in the automobile applications, construction of buildings, machinery, and appliances as these materials are effectively reused, recycled, or disposed with minimum impact on the environment. As such, it has become mandatory to incorporate sustainable, environmental friendly and green concepts in the development of new materials and processes. The primary objective of this study is to manufacture composites using fibers obtained from Thespesia Lampas plants, which are known for their soft, long fibers that are commonly used in various domestic products. The composites are made by combining these fibers with a general purpose polyisocyanurate resin, and their potential applications in both domestic and commercial products are explored. To evaluate the properties of these composites, tests are conducted for tensile strength, flexure, and water absorption.

Controlled Autoignition (CAI) is a very promising technology for simultaneous reduction of fuel consumption and engine-out emissions [3, 4, 9, 16]. But the operating range of this combustion mode is limited on the one hand by high pressure gradients with the subsequent occurrence of knocking, increasing NOX-emissions and cyclic variations, and on the other hand by limited operating stability due to low mixture temperatures. At higher loads the required amount of internal EGR decrease to reach self-ignition conditions decrease and hence the influence of the ignition spark gain. The timing of the ignition spark highly influence the combustion process at higher loads. With the ignition spark, pre-reactions are initialized with a defined heat release. Thus the location of inflammation and flame propagation can be strongly influenced and cyclic variations at higher loads can be reduced.

In this work, heat loss was investigated in two different HCCI single cylinder engines. Thermocouples were adapted to the surfaces of the cylinder heads and the temperature oscillations were detected in a wide range of the engine operation conditions. The local heat transfer is analyzed with port fuel and direct injection, for different engine parameters and operating points. It is shown that the spatially averaged measured heat loss in HCCI operation represents the global heat loss well. The spatial variations are small in the operation map presuming stable operating points with low cyclic variations and good engine performance. Furthermore, the heat loss measured in HCCI operation is compared to the heat loss detected in homogeneous and stratified DI-SI operation in the same engine. It is shown that the local heat losses in stratified DI-SI operation show large variations, depending on the direction of the flame propagation.

In this work, heat loss was investigated in homogeneous and stratified DI-SI operation mode in a single cylinder research engine. Several thermocouples were adapted to the combustion chamber surfaces. The crank angle resolved temperature oscillations at the cylinder head and piston surface could thereby be measured in homogeneous and stratified operation mode. A grasshopper linkage was designed and adapted to the engine, to transfer the piston signals to the data acquisition device. The design of the experimental apparatus is described briefly. For both operation modes the average steady-state temperatures of the combustion chamber surfaces were compared. The temperature distribution along the individual sensor positions at the cylinder head and piston surface are shown. Furthermore, the curves of the crank angle resolved temperature oscillations in stratified and homogeneous operation mode were compared.