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This paper will summarize the theoretical and experimental achivements in the thermal load studies which have been done, especially determination of the heat exchange boundary conditions, some new methods will be proposed. This made it possible to predict the distributions of the temperature and the heat flux in heated components, when the engine is still in the design stage. Using the aformentional achievements in the thermal load studies, several types of the engines have been designed and developed. Those high speed small air-cooled diesel engines have been successfully applied to the agricultural and industrial multipurpose utilities in the wide area.

Nano Enhanced Phase Change Material (PCM) is proposed as Battery Thermal Management System. by nature, the pure paraffin has low thermal conductivity and sub-cooling characteristics. In order to increase the thermal conductivity of PCM, thermal conductive substance such as nanoparticles are added to PCM, SiO2 nanoparticles were dispersed into paraffin wax tosynthesisSiO2 –PCM nanocomposites. The chemical, physical and thermal properties of CPCMs were determined by various material characteristic techniques. The TGA and DTG results show that all CPCMs have good thermal and chemical stability. With the addition of SiO2 improved the thermal and chemical stability of pure paraffin The latent–heat of fusion was decreased with increasing the loading of SiO2 and also the thermal conductivities of CPCM increased.

Reduction of the drag torque and longevity of the clutch assembly are the most important factors for vehicle transmission improvement. The decreasing trend of the drag torque with speed after its peak is a common characteristic of the clutch assembly. Several theoretical models have been presented by the researchers describing the drag torque characteristics at lower clutch speed. However, very little study has been made on the drag torque behavior at very high clutch speed (6000∼10000+ rpm). The alarming jump of the drag torque at high speed operating condition remains unexplained till date. In this paper, we investigated the possible reasons of torque jump up at high rotation speed and solution to overcome this problem. We presented an analytical correlation of torque jump up with the excessive decrease of local static pressure and assumed that vacuum formation is the possible reason of high speed torque rising and associated vibration.

Transient emissions of a turbocharged three-litre V6 diesel engine fuelled by hydrogenated vegetable oil (HVO) blends were experimentally investigated and compared with transient emissions of diesel as reference. The transient emissions measurements were made by highly-dynamic emissions instrumentations including Cambustion HFR500, CLD500 and DMS500 particulate analyzer. The HVO blends used in this study were 30% and 60% of HVO in diesel by volume. The transient conditions were simulated by load increases over 5 s, 10 s and 20 s durations at a constant engine speed. The particulate, NO, HC concentrations were measured to investigate the mechanism of emission formation under such transient schedules. The results showed that as the load increased, NO concentrations initially had a small drop before dramatically increasing for all the fuels investigated which can be associated with the turbocharger lag during the load transient.

The paper presents the comparative study on the antiwear properties of zinc oxide and Cu-Zn mixed oxide nanoparticles, as additive in SAE20W40 engine oil. The nanoparticles were prepared using precipitation method and characterized using scanning microscopy imaging technique and XRD analysis. The particle size was found to be between 70-80 nm.The stability of the nanosuspension play a vital role in the antiwear performance. Therefore the stability studies were carried out by dispersing varying concentration of nanoparticle between 0.01wt% - 0.05wt% in the engine oil using surface modifiers and sonication. Nanosuspensions above 0.02 wt% of nanoparticles showed sedimentation on long standing for 36h. Based on this, the concentration of nanoparticle in the engine oil was optimized as 0.01 and 0.02wt%.The nanosuspensions with optimized concentration i.e.0.01wt% ZnO, 0.02 wt% ZnO, 0.01wt% Cu-Zn and 0.02 wt% Cu- Zn mixed oxides were tested for antiwear property using four ball tester.

Austempered ductile iron (ADI) is an alternative to hardened steel for machined parts with high hardness, ductility, strength and fatigue strength. The optimal cutting parameters to perform turning operation on ADI with PCBN insert are predicted through the response surface methodology (RSM) approach. Design Expert Software was used to design fifteen experiment trials by changing cutting parameters including speed (N) rpm, feed (f) mm/min, and depth of cut (d) mm. The outcomes of the experiments were then examined. The mathematical model determined in the Analysis of Variance (ANOVA) satisfied output responses concerning the input parameters. The optimal turning parameters, N: 1039.11 rpm, f: .5 mm/min and d: 0.0974 mm is revealed the both responses. The confirmation experiment results revealed that the predicted value of responses is better in agreement with experimented responses.

The objective of this work is to examine the suitability of cooling airflow non-uniformity on radiator frontal surface as a factor to evaluate three attributes: airflow distribution, front fascia geometry and deterioration in heat rejection. In literature, the effect of front end design is investigated by evaluating the volume of cooling airflow passing through the radiator and cooling drag of a vehicle. In this study, it was demonstrated that airflow distribution on radiator frontal surface can also be considered as one of the parameters while choosing the front-end design. Using the basic equations for modeling the cooling airflow through a front-end opening, CFD approach is developed to quantify the airflow distribution over the heat exchanger(radiator) as a function of flow statistics of the upstream cooling air. Further, this work is extended to study the impact of airflow non-uniformity on the thermal performance of radiator using the empirical equation available in literature.

When developing diesel exhaust aftertreatment systems the often constrained packaging envelope is a challenge. In addition, the stringent emission legislation can necessitate the injection of additives, for example urea and/or hydrocarbons, to achieve performance targets. In such cases, a good distribution of reactants over the catalyst surface is beneficial but might be difficult to achieve. The uniformity of these distributions is often studied separately using a non-dimensional measure denoted as the Uniformity Index (UI). However, a combination of the exhaust gas UI and the UI for the additive is also interesting to study. In this work the origin, applicability and advantages of the uniformity index is discussed as a guide for developing diesel exhaust aftertreatment systems. Moreover, a matching index (UIα) is proposed for the analysis of systems where additives are injected. It is found that two skew distributions can give a good conversion if the profiles match.

In automobile, NVH has been playing an important role in defining the overall quality of the vehicle. Continuous efforts are being put in globally by engineers to make the travel experience as comfortable as possible for both commercial and passenger segment vehicles. The front wiping system being a critical safety feature in an automobile is one of the sources of structural vibrations/noise due to numerous moving child parts. Therefore, the layout of the wiper motor in the vehicle is an important aspect of Vehicle NVH. These vibrations and noise levels become more pronounced if the wiper motor is mounted inside the passenger compartment, a layout that is commonly seen in commercial vehicles. This paper focuses on measures to improve the NVH while having the layout of the wiping system inside the passenger compartment of the vehicle.

As automobiles become increasingly quieter, the wiper operation noise becomes more noticeable by the customer. This paper deals with the experimental approach and the methodology to investigate the Friction induced wiping noise. Role of design in a wiper system plays a very imperative task in meeting the performance of wipers but at the same time it does not cater to the NVH issues. Some of the important design parameters which affect the NVH properties of the wiper system are highlighted in this paper. For better understanding of the system some of the best in class vehicles for SUV category were tested and compared with our test vehicle. In this study more importance given to analytical part which is more important to investigate and in depth study of the friction induced noise. For analytical study some techniques such as time frequency domain i.e. Wavelet transforms, frequency domain and time domain where extensively used.

An investigation on the sequential turbocharging (ST) of a Kelvin TFSC6 medium speed diesel engine developing 320 kW at 1200 r/min is reported in this paper. The sequential turbocharging (ST) system, utilising turbochargers of unequal size, resulted in significant improvement when compared with previously designed systems. The engine test results show that the new ST system improves the engine performance at both high and low speeds except, at or near to, the ‘transfer’ speed. The engine low speed performance is improved with fuel saving of up to 7 g/kwh for the 1st sequence. However, the improvement of the high engine speed performance at the 2nd sequence was limited by some boost air leakage from a flexible connecting pipe from the peak unit compressor outlet to the intercooler inlet. An optimised sequence transfer control mode is also proposed in this research.

It is well known that the catalytic efficiency and durability of an automotive catalytic converter can be significantly affected by its design. This paper demonstrates the potential for further improvement in both the durability and efficiency by using a novel catalytic converter concept based on a large frontal area, high cell density substrate. This concept requires that attention be paid to optimization of the flow as well as of the mounting system. The converter design is determined with a computational fluid dynamic (CFD) simulation and the effect of this design on the temperature distribution in the substrate is calculated and measured. Due to this novel converter concept the maximum substrate temperature is reduced, which results in a better aging behavior. This improvement allows a reduction in precious metal content without a loss in efficiency.

The high frequency of fatal head injuries is one of the important issues in traffic safety, and Traumatic Brain Injuries (TBIs) without skull fracture account for approximately half of them in both occupant and pedestrian crashes. In order to evaluate vehicle safety performance for TBIs in these crashes using anthropomorphic test dummies (ATDs), a comprehensive injury criterion calculated from the rotational rigid motion of the head is required. While many studies have been conducted to investigate such an injury criterion with a focus on diffuse brain injuries in occupant crashes, there have been only a limited number of studies focusing on pedestrian impacts. The objective of this study is to develop a comprehensive injury criterion based on the rotational rigid body motion of the head suitable for both occupant and pedestrian crashes.

Natural gas as a fuel for internal combustion engines is a combustion technology showing great promise for the reduction of CO2 and particulate matter. To demonstrate the potential of natural gas direct injection, especially in combination with supercharging, some experimental investigations were carried out using a single-cylinder engine unit with lateral injector position. For this purpose different injection valve nozzles, piston crown geometries as well as operating strategies were investigated. First experimental results show that it is also possible to better support the combustion process by providing a late injection of a part of the fuel, near ignition point, so that the additional induced turbulence can speed up the flame propagation 1 Mixture formation with gaseous fuels due to its low mass density is more critical than in gasoline engines, because even high injection velocities still produce very low fuel penetration.

The strength and wear resistance of four alloyed cast irons with elements like Ni. Mo, Cu, Cr and Al have been compared and analyzed. The increased hardness is reducing the wear resistance of the alloy due to graphite flakes. Higher carbon produces more graphite flakes which act as weak points for reducing strength and wear resistance. The wear rate increases for harder cast iron sample with more graphite flakes. Wear rate drastically increases with increase in carbon equivalent. Strength was found to decrease for samples with higher graphite flakes. The wear debris consisted of graphite flakes in platelet like morphology along with iron particles from the matrix. The presence of carbon at the sliding interface also sometimes decreases wear rate.

Particulate matter (PM) emission from direct-injection (DI) gasoline engines are caused by pool combustion of fuel adhering on a piston wall. It is necessary to clarify the formation process of liquid fuel film. In this study, temporal change of fuel mass adhered on the wall was evaluated to understand the adhesion process of a liquid fuel film by using total internal reflection laser-induced fluorescence (TIR-LIF) technique. As a result, the mass of the liquid film increased during the fuel injection period, and it decreased rapidly during the period that spray tail after the end of injection reached the wall surface.

Different solutions for trunk floors recently presented on the market have been collated and investigated in order to better define the possible features integrated and the acoustic performance of trunk load floors. A description protocol has been devised and applied to systematically categorize the whole set of features potentially characterizing a trunk floor, and the wide range of solutions used with respect to materials, processes and design configurations. The acoustic performance has been specifically addressed with the evaluation of the acoustic absorption on both sides and a specific testing procedure to evaluate the noise insulation capability provided by actual parts.

The authors carried out a basic and systematic investigation on diesel combustion processes using three different experimental apparatuses. This paper summarized the experimental results obtained from the three devices. Among the data contained in this paper are; (1) The structure and shape of diesel spray, the air movement around diesel spray and the spatial and temporal distributions of the size of droplets in diesel spray injected into the high pressure and room temperature charge. (2) The shape of diesel spray injected into the high pressure and high tempertaure charge. (3) The characteraistics of flame, and illumination delay, and ignition delay in the high pressure and high temperature charge.

The deformation of injector components cannot be disregarded as the pressure of the system increases. Deformation directly affects the characteristics of needle movement and injection quantity. In this study, structural deformation of the nozzle, the needle and the control plunger under different pressures is calculated by a simulation model. The value of the deformation of injector components is calculated and the maximum deformation location is also determined. Furthermore, the calculated results indicates that the deformation of the control plunger increases the control chamber volume and the cross-section area between the needle and the needle seat. A MATLAB model is established to The influence of structural deformation on needle movement characteristics and injection quantity is investigate by a numerical model. The results show that the characteristic points of needle movement are delayed and injection quantity increases due to the deformation.

In order to clarify certain aspects of the combustion process in differentially cooled engines, a special engine was built in which the surface temperatures of the piston crown, cylinder liner and cylinder head bottom could be varied independently. A computer programme to calculate the swirl and turbulence intensity in the combustion chamber was developed. Investigations showed that in order to improve the mixing process, the liner temperature should be kept low while the piston temperature may be increased only if the cylinder head temperature is kept low, and vice versa. A low coefficient of regression in the plotted results indicated that the flow parameters Investigated were not the determining parameters but only one among many others which need further investigation. The present investigation however Indicates that the high piston temperature found desirable earlier should preferably be combined with low cylinder head and liner temperatures.