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In the second option gas fuel is injected into the main chamber by a direct injector and ignited by the direct injection of a small quantity of Diesel fuel. Injection and ignition may be tuned to control the amount of premixed and diffusion combustion to produce the best fuel conversion efficiency vs. load and speed requirements within the prescribed pressure and temperature constraints. ...The paper presents a novel concept of a very efficient transportation engines for operation with CNG, LNG or LPG. The paper considers the options of single fuel design with jet ignition and dual fuel design with Diesel and gas. ...Injection and ignition may be tuned to control the amount of premixed and diffusion combustion to produce the best fuel conversion efficiency vs. load and speed requirements within the prescribed pressure and temperature constraints.

It is well known that carbonitriding can bring benefits compared to standard carburising particularly for shallow case depths. The major benefits are an increased effective case depth in a given time and a higher case hardenability. The major drawback of the process is that it can only be carried out at relatively low temperatures. If ammonia is used as the source of nitrogen, the time required to achieve deeper cases can be significantly longer than for the equivalent higher temperature carburising process. For carbonitriding to be effective at higher temperatures, another source of nitrogen is required that so that it can produce the nascent nitrogen necessary for diffusion at higher processing temperatures. Several sources of nitrogen were investigated. One was found that produced a significant carbonitriding effect at higher temperatures. Samples of SAE8720 and SAE9315 were carburised and carbonitrided under identical conditions and the case depths compared.

Laser scanners are typically used in vehicle accident reconstruction and forensic applications to measure roadway and vehicle details. However, laser scanners used near congested roadways can digitize unwanted passing vehicles, which produces a scan with noisy and poor image quality point clouds. On the other hand, small Unmanned Aircraft System (sUAS) images of reflective objects may result in a less accurate mesh, and capturing vertical surfaces such as telephone poles, traffic lights, and building faces is more difficult. Prior research has tested the accuracy of sUAS-captured images processed with commercially available software, such as AgiSoft or Pix4D, as well as in comparison to the accuracy of laser scan data. Research still has yet to be conducted on combining the laser scans and sUAS images for use in accident reconstruction and other forensic settings.

To enable the exploitation of such high EGR rates with acceptable soot penalties, a two-stage turbocharger and an extremely high-pressure fuel injection system (up to 3000 bar) were adopted. Moreover, post injections events were also exploited to further mitigate soot emissions with acceptable Brake Specific Fuel Consumption (BSFC) penalties. ...In this paper, a numerical and experimental assessment of post injection potential for soot emissions mitigation in an off-road diesel engine is presented, with the aim of supporting hardware selection and engine calibration processes. ...Since the selection of the post injection calibration parameters (such as injected quantity and dwell time) is crucial to maximizing its efficacy, a 3D-CFD engine model was built and calibrated to evaluate its effects on soot emissions and fuel consumption.

Additionally, a crank angle resolved in-cycle NOx formation model is utilized to calculate the urea injection duration for each individual injection event. A gas temperature model based on the cylinder pressure is also used to decide the timing of the urea injection, although always occurring after the combustion and during the expansion stroke. ...A gas temperature model based on the cylinder pressure is also used to decide the timing of the urea injection, although always occurring after the combustion and during the expansion stroke. A parameter sweep is conducted to evaluate the concept where also an SCR-catalyst has been introduced to the engine system. ...The parameter sweep done in the study contains sweeps of engine speed, rail pressure, engine load, EGR levels and timing of the urea injection (by changing the gas temperature limit at which the injection of urea is initiated). The engine tested is a modified single cylinder Scania D13 engine, rebuilt from a six-cylinder engine.

This paper present some data on air flow in the model combustion chamber, some films of fuel injection spray, combustion flame propagation, using high speed camera, and test datas of combustion characteristics. ...In order to investigate the combustion process of a Direct Injection Stratified Charge Rotary Engine (DISC-RE), a statical model combustion chamber was made and 2 stroke diesel engine was used as a Rapid Compression Machine (RCM) for the purpose of fundamental study of some characteristics of DISC-RE operation. ...Generally to take a photograph inside of combustion chamber is very difficult using actual engine, because the combustion chamber moves toward rotational direction, so, using the static combustion chamber is very effective in the study of the fundamental process.

This work focuses on the transition from HCCI to PPC and combustion and emissions characteristics during the process are investigated. Injection strategies, EGR and boost pressure were the main parameters used to present the corresponding effect during the transition. ...Partially premixed combustion (PPC) is a promising way to achieve high efficiency and low engine-out emissions simultaneously in a heavy-duty engine. ...Compared to Homogeneous Charge Compression Ignition (HCCI), it can be controlled by injection events and much lower HC and CO emissions can be achieved. This work focuses on the transition from HCCI to PPC and combustion and emissions characteristics during the process are investigated.

The combustion process of methanol is then observed by the method of high-speed Schlieren photography to clarify the mode of methanol combustion. A new methanol DISC combustion system having a protrusion in the combustion chamber is devised based on such results. ...For the purpose of developing direct injection heavy-duty methanol engines which surpass diesel engines in purformace, this paper first clarifies the methanol concentration around the spark plug for achieving a high ignition stability by sampling the gas near the spark plug using a sampling valve. ...For the purpose of developing direct injection heavy-duty methanol engines which surpass diesel engines in purformace, this paper first clarifies the methanol concentration around the spark plug for achieving a high ignition stability by sampling the gas near the spark plug using a sampling valve. The combustion process of methanol is then observed by the method of high-speed Schlieren photography to clarify the mode of methanol combustion.

To cope with these mandates, developers of engines and related equipment are aiming to break new ground in the fields of combustion, fuel and hardware technologies. In this work, a novel diesel fuel injector, Delphi’s DFI7, is utilized to experimentally investigate and compare the performance of ramped injection rates versus traditional square fueling profiles. ...In this work, a novel diesel fuel injector, Delphi’s DFI7, is utilized to experimentally investigate and compare the performance of ramped injection rates versus traditional square fueling profiles. The aim is specifically to shift the efficiency and NOx tradeoff to a more favorable position. ...Tests were carried out at 1200 and 1425 rpm; for the latter engine speed peak efficiency was attained at considerably lower NOx levels by applying a ramped injection rate. Particulate matter emissions, on the other hand, are generally lower with the use of square profiles.

A combustion system has been developed to burn neat (pure) methanol in a direct-injection four-stroke-cycle engine. ...A glow plug was placed in a modified quiescent combustion chamber to ensure reliable methanol ignition at all engine operating conditions. The methanol engine provides thermal efficiency nearly equal to the diesel engine from which it is derived, in addition, nitrogen oxide emissions are reduced by 50 percent and exhaust smoke is negligible.

A novel Blended Hydraulic Hybrid transmission architecture is presented in this paper with benefits over conventional designs. ...A novel Blended Hydraulic Hybrid transmission architecture is presented in this paper with benefits over conventional designs. This novel configuration combines elements of a hydrostatic transmission, a parallel hybrid, and a selectively connectable high pressure accumulator using passive and actively controlled logic elements. ...To explore the novel blended hybrid architecture six transmissions were modeled and simulated. These included baseline manual and automatic transmissions, conventional series hybrid and series hybrid power split transmissions, and the novel blended hybrid and blended hybrid power split transmissions.

The paper takes the hybrid track-type dozers (TTDs) as an example and proposes an optimal design of a novel power-split powertrain for TTDs. The commercial hybrid TTD usually adopts the series hybrid powertrain, and sometimes with an extra steering mechanism, which has led to low efficiency and made the structure more complicated. ...The control results show that the novel design has better drivability and fuel economy than the series hybrid benchmark. The proposed new kind of powertrain has shown good potential which can be considered for future industrial application.

The research presented in this paper focuses on the use of novel, non-contact torque sensors to measure the driveline torque distribution. The example vehicle is a four wheel drive (4WD) agricultural tractor - but it is proposed that the same measurement techniques could be applied to any off-road vehicle.

This paper focuses on the development of a new mode-switching hybrid which is a novel combination of a hydrostatic transmission and a series hybrid. This architecture initially operates in hydrostatic mode offering a stiff response and later when the system demands higher pressure, the mode of operation can be switched to secondary control like in series hybrid using an on-off valve.

A robust control method applied to a DC-motor the actuator of a steering system installed on a radio-controlled multiloader truck is developed Requirements for the control system are robustness and stability against disturbances and change in plant characteristics, and rapid and accurate response to steering commands To comply with these requirements, we applied a robust model matching (RMM) control method to the steering actuator Results of simulation analyses and a hardware-in-the-loop simulation show the effectiveness of this control method

Conventional electric vehicles adopt either single-speed transmissions or direct drive architecture in order to reduce cost, losses and mass. However, the integration of optimized multiple-speed transmissions is considered as a feasible method to enhance EVs performances, (i.e. top speed, acceleration and grade climbing), improving powertrain efficiency, saving battery energy and reducing customer costs. Perfectly in line with these objectives, this paper presents a patented fully integrated electric traction system, as scalable solution for electrifying light duty passenger and commercial vehicles (1.5-4.2 tons), with a focus on minibuses (<20 seats). The adoption of high-speed motor coupled to multiple-speed transmission offers the possibility of a relevant efficiency improvement, a 50% volume reduction with respect to a traditional transmission, superior output torque and power density.

Reliability research in hybrid ceramic bearings involves life testing of hybrid bearings and ceramic specimens. New materials for bearings like advanced ceramics have emerged for evaluation in recent years. In fatigue testing to determine the stress-life relationship, the number of sample size in life testing can be limited by consideration of cost and testing time. In the testing of ceramics, some researchers have relied on the use of a stepwise multiple loading approach to increase the failure data points. In this paper, a maximum likelihood method is applied to test data with multiple loads to estimate the stress-life exponent. This method treats the data at different loads or steps at once. Test data from three fatigue experiments using silicon nitride materials have been analyzed to obtain the stress-life exponents. Also, Weibull plots of the ‘equivalent lives' have been presented for all test specimens tested at different loads and load steps.

Gear tooth friction directly influences power losses and temperature rise as well as system dynamic behavior. Recently it attracted many attentions as friction is considered one of the main sources of power losses in geared systems, such as in automotive transmissions. Coefficient of friction has been found not a constant but varies with different contact conditions, which partly makes the measurement of friction a difficult and expensive process. Therefore an analytical model that is capable of predicting it accurately becomes very much demanded. A few empirical formulae based on experimental data and analytical models based on lubrication theory are found in the literature. However, they are either not suitable for a general gear contact or too complex to adapt in gearing. In this paper, a new coefficient of sliding friction based on a thermal Elastohydrodynamic Lubrication (EHL) model is developed by a multiple linear regression analysis.

Four cases were identified: a) main injection during the mixing phase of pilot injection; b) main injection during the premixed phase of pilot combustion; c) main injection during the diffusive phase of pilot combustion and d) main injection after pilot combustion was completed. ...Combinations of pilot injection parameters i.e. pilot start of injection, pilot mass, pilot-main injection separation, and rail pressure were studied for various operating conditions and combustion phases. ...It was concluded that the effect of pilot-injection combustion on main injection can be studied based on the phase of pilot combustion at the start of main injection. Four cases were identified: a) main injection during the mixing phase of pilot injection; b) main injection during the premixed phase of pilot combustion; c) main injection during the diffusive phase of pilot combustion and d) main injection after pilot combustion was completed.

To study diving accidents of passenger cars into water, staged experiments with full-scale vehicles driven by a professional stunt-man and a corresponding 1/10 scale model were performed. ...The paper shows that diving accidents of automobile into the water can be studied with scale models and makes few suggestions how to escape for survival.