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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.

BSR noise is an important parameters for customer discomfort. According to a market survey, squeaks and rattles are the third most important customer concern in cars after six months of ownership. The high quality acoustic environment of a car, annoying noises like buzz, squeak, and rattle is related to various parameters such as material assembly, tolerance, aging, humidity, surface contact, and surface hardness. BSR is originated from frictional movement between two parts or from the impact between two parts. The rattle noise is caused when surfaces close to each other move perpendicular to each other due to insufficient attachments or insufficient structural strength. In our study, we have shown the impact of various front suspension component in front suspension assembly on BSR noise and also the method to detect and attenuate the same. A methodical analysis process is shown to identify the contributing part and resolve the BSR issue.

Nowadays automotive cabin comfort has become a necessity rather than an optional feature, with customers demanding more comfort features. Thermal comfort becomes an essential part of this expectation. Since steering wheel is the first surface that the driver will touch once he enters the vehicle, maintaining thermal comfort of steering wheel becomes important, especially in tropical countries like India where a car parked in hot weather can get significantly warm inside. In this work, two design concepts for automotive steering wheel thermal control based on thermoelectric effect are depicted along with a detailed mathematical model. Thermoelectric coolers were selected for this purpose as it is solid state, compact & scalable solution to achieve rapid cooling rates. This was the desired feature expected from an integration standpoint in automotive architecture.

This paper presents results from tests using a fuel injection system which uses an ultrasonic atomizer paired with a port fuel injector (PFI). This concept was tested on a four stroke 200 cc spark-ignited two-wheeler engine. A throttle body with a PFI mounted on it was added to the air intake path of the engine, replacing the conventional carburetor. The ultrasonic disc was mounted in such a way, that the injected fuel from the PFI, falls directly on the face of the disc. The atomizer and the PFI were timed and synchronized appropriately using an Arduino® microcontroller, to promote atomization and vaporization of the fuel injected. The atomizer disc was excited using a high frequency oscillator circuit. The engine could be tested at various speeds and loads, corresponding to points which lie on the local drive duty cycle. The engine test results showed improvement in the engine exhaust emissions.

The upcoming Bharat Stage VI (BS VI) emission legislation has put enormous pressure on the future of small diesel engines which are widely used in the Indian market. The present work investigates the emission reduction potential of a common rail direct injection single cylinder diesel engine by adopting a holistic approach of lowering the compression ratio, boosting the intake air and down-speeding the engine. Experimental investigations were conducted across the entire operating map of a mass-production, light-duty diesel engine to examine the benefits of the proposed approach and the results are quantified for the modified Indian drive cycle (MIDC). By reducing the compression ratio from 18:1 to 14:1, the oxides of nitrogen (NOx) and soot emissions are reduced by 40% and 75% respectively. However, a significant penalty in fuel economy, unburned hydrocarbon (HC) and carbon monoxide (CO) emissions are observed with the reduced compression ratio.

Engine performance and emission control are key attributes in the overall engine development in which sealing of the mating components plays an important role to achieve the same. Rubber gaskets are being used for sealing of different Internal Combustion (IC) engine components. Gasket sealing performance needs to be ensured at initial development stage to avoid the design changes at the later part of development cycle. Design changes at later stage of development can potentially influence parameters like optimization, cost and time to market. Demand of utilization of virtual tools (front loading) is growing with the increasing challenges like stringent product development cycle time and overall project cost. This paper describes a procedure to simulate the rubber gasket and groove for different material conditions (dimensional tolerances). This entire simulation is divided into two phases. In the first phase of the simulation, Load Deflection curve (LD curve) is established.

This paper presents the experimental investigation of combustion stability and nano-particle emissions from the CNG-diesel RCCI engine. A modified automotive diesel engine is used to operate in RCCI combustion mode. An open ECU is used to control the low and high reactivity fuel injection events. The engine is tested for fixed engine speed and two different engine load conditions. The tests performed for various port-injected CNG masses and diesel injection timings, including single and double diesel injection strategy. Several consecutive engine cycles are recorded using in-cylinder combustion pressure measurement system. Statistical and return map techniques are used to investigate the combustion stability in the CNG-diesel RCCI engine. Differential mobility spectrometer is used for the measurement of particle number concentration and particle-size and number distribution. It is found that advanced diesel injection timing leading to higher cyclic combustion variations.

Stringent emission regulations on one hand and increasing demand for better fuel economy along with lower noise levels on the other hand require adoption of advanced common-rail direct-injection technologies in diesel engines. In the present work, a small 0.9-l, naturally aspirated, two-cylinder, common-rail direct-injection diesel engine is used for the analysis of combustion noise at different engine operating conditions. Experiments are conducted at different loads and engine speeds, incorporating both single and multiple (i.e. pilot and main) injections along with different injection timings. In the case of multiple injections, the influence of pilot injection quantity is also evaluated on the combustion noise while maintaining the same load. In-cylinder pressure was recorded with the resolution of 0.1 crank angle degree, and it was used for the quantitative analysis of noise assessed from the resulting cylinder pressure spectra, and sound pressure level.

In a direct-injection (DI) engine, charge motion and mixture preparation are among the most important factors deciding the performance and emissions. This work was focused on studying the effect of injector positioning on fuel-air mixture preparation and fuel impingement on in-cylinder surfaces during the homogeneous mode of operation in a naturally aspirated, small bore, 0.2 l, light-duty, air-cooled, four-stroke, spark-ignition engine modified to operate under the DI mode. A commercially available, six-hole, solenoid-operated injector was used. Two injector locations were identified based on the availability of the space on the cylinder head. One location yielded the spray-guided (SG) configuration, with one of the spray plumes targeted towards the spark plug. In the second location, the spray plumes were targeted towards the piston top in a wall-guided (WG) configuration so as to minimize the impingement of fuel on the liner.

The proposed paper describes the hardware and software method used for detection of wash fluid level in water tank used in automotive; thereby eliminating the need for sensor (Reed type switch mounted on washer bottle) for low wash fluid detection. Wash motor is used for water spray on windscreen during wash and wipe operation. The proposed system makes use of hardware circuit used to drive the wash motor usually of DC (Direct current) type and a feedback circuitry to read back the current consumed by motor during particular wash operation. This hardware system is coupled with software algorithm such that during IGNITION ON instance wash motor will be turned on such as to get motor current readings to determine amount of load operated by motor which is related to wash fluid inside the washer bottle. Motor operation is optimized so as to avoid water spray causing nuisance to user.

In the past five years, Indian cities have been consistently appearing in the list of top 15 world’s most polluted cities. Every day, a common man in India spends more than 2 hours on the road due to numerous reasons, thus exposed to inhale highly polluted air. Further, the passenger car users is exposed to ~ 6 times more polluted air as compared to ambient air reason being the air is recirculated through the air conditioning system. Prolonged exposure to such polluted/ recirculated air shows increasing trend in respiratory illnesses, breathing discomfort and fatigue. This paper discusses the key challenges involved in incorporating cabin air filter as cabin air quality enhancer in current mobility solutions.

Non-Asbestos Organic (NAO) brake- material research has been significant in the last decade in an attempt to replace the conventional semi-metallic and asbestos based materials. Influence of ingredients in this multi-ingredient (generally 10-25 in different proportions) system on performance properties, however, is still not thoroughly researched area because of complexity involved and needs intensive efforts to understand this aspect. Graphite is one of the most important and almost inevitable ingredients in friction materials. A wide variety of graphite varying in origin, particle size, crystallinity, thermal conductivity etc. is used by the industry. An in-depth and systematic study on the influence of size of graphite on tribo-performance, however, is not available.

The effect of variation in injection pressure and Injection timing on the performance and exhaust emission characteristics of a direct injection, naturally aspirated Diesel engine operating on Diesel and Diesel-Biodiesel Blends were studied. A three-way factorial design consisting of four levels of injection pressure (150,210, 265,320 bar), four levels of injection timing (19° btdc, 21.5° btdc, 26° btdc, and 30.5° btdc) and five different fuel types (D100, B10, B20, B40, and B60) were employed in this test. The experimental analysis shows that when operating with Linseed Oil Methyl Ester-Diesel blends, we could increase the injection pressure by about 25% over the normal value of 20MPa. The engine performance and exhaust emission characteristics of the engine operating on the ester fuels at advanced injection timing were better than when operating at increased injection pressure.

Biodiesel developed from non- edible seeds grown in the wasteland in India can be very effectively utilized in the existing diesel engines used for various applications. This paper presents the results of investigations carried out in studying the fuel properties of mahua oil methyl ester (MOME) and its blend with diesel from 20% to 80% by volume. These properties were found to be comparable to diesel and confirming to both the American and Indian standards. The performance of mahua biodiesel (MOME) and its blend with diesel in a Kirloskar DAF8 engine has been observed. The addition of MOME to diesel fuel has significantly reduced CO, UBHC and smoke emissions but increases the NOx emission slightly. The reductions in exhaust emissions could help in controlling air pollution. The results show that no significant power reduction in the engine operation when operated with blends of MOME and diesel fuel.

EU directive 2005/64/EC on type approval of motor vehicles with respect to their Reusability, Recyclability and Recoverability ( RRR ) requires vehicle manufacturers to put in place the necessary arrangements and procedures for Parts, Materials and Weight (PMW ) data collection from full chain of supply. This is required to perform the calculations of recyclability rate and recoverability rate in line with ISO 22628. Commonly practiced data collection methodologies included spreadsheet and use of internationally available IT support system for collection of material data. Data complexity and prohibitive cost for using Internationally available IT Support systems like IMDS (International Material Data System) has led to the in-house development of IT enabled Solution customizing Siemens PLM software product (Team centre Enterprise) and SAP (SRM suite).

A large number of metal cutting inserts are used in the manufacturing of automobile parts. These are made from hard metals like Carbide, Ceramic, Cermet, PCD and CBN. Since making of these hard metal inserts involve a high amount of energy in addition to natural resources namely Titanium, Tungsten, Cobalt etc, any attempt made therefore for reusing of the used up inserts will benefit environment because this reuse will lower down the demand on natural resource. Reuse can be done in a number of ways [ 1 ]. Many of these recycling techniques involve removing the dull portion developed during the first use by re sharpening [ 2 ]. A different approach is being suggested here in which used up inserts can be used directly. This approach leads to use of the unused cutting edges /corners of the insert without any re sharpening. Thus the cost of machining becomes half of the original cost or even more depending on the application for reuse.

A single cylinder, direct injection diesel engine was run on water diesel emulsion at a constant speed of 1500 rpm under variable load conditions. Water to diesel ratio of 0.4 on the mass basis was used. Tests indicated a considerable reduction in smoke and NO levels. This was accompanied by an increase in brake thermal efficiency at high outputs. HC & CO levels, ignition delay and rate of pressure rise went up. The heat release rate in the premixed burn period was higher. When the oxygen concentration in the intake air was enhanced in steps up to 25% along with the use of water diesel emulsion, the brake thermal efficiency was improved and there was a further reduction in the smoke level. HC and CO levels also dropped. NO emission went up due to increased temperature and oxygen availability. An oxygen concentration of 24% by volume was optimal as the NO levels were near about base diesel values.

Performance of a Current generation catalytic converter using Pd/Rh (10:1) as binary catalyst impeded on an ultra thin ceramic substrate and alumina wash coat is modeled for performance prediction and parametric optimization. Kinetic rates for the catalyst are reduced after conducting series of experiments on a passenger car engine. A new concept in mass transfer coefficient is introduced for improving accuracy of the model prediction. In order to take care of the precious metal resources and to become independent of precious metal price fluctuation, a new pattern of loading of precious metal is suggested for optimum performance and metal savings about 46 percent was observed. Experimental investigations were carried out to validate the established kinetic rates over a wide range operation of the engine and for the model validation. Satisfactory agreements are observed for the model prediction and experimental results.

With increased awareness about environmental issues, the trend of automobile industry is to use ‘Recycled’ or ‘Biodegradable’ or ‘Energy Recoverable’ material. As a part of this programme, to make the vehicle ‘Green’ in nature, many automobile OEMs have taken the initiative to make use of natural fibre composite in their vehicles. Natural fibre based composite has been successfully proven for less critical as well as for semi-structural applications in an automobile. These typical applications are insulations, headlining, carpets, door pad etc. There is a demanding task for automotive OEMs to meet 85% Recyclability and 95% Recoverability targets by year 2015. To meet the RRR (Reuse, Recycle & Recover) and the ELV (End of Life) regulatory requirements, increased use of natural fibre based composite/ biopolymers is unavoidable. Natural fibre can offer potential advantages such as weight saving and improve overall green rating of the vehicle.

This paper quantifies and compares the cooling performance and refrigerant and fuel cost savings to automobile manufacturers and owners of secondary-loop mobile air conditioners (SL-MACs) using refrigerants hydrofluorocarbon (HFC)-134a and the available alternatives HFC-152a and HFO-1234yf. HFC-152a and HFO-1234yf are approved for use by the United States Environmental Protection Agency (US EPA) and satisfy the requirements of the European Union (EU) F-Gas Regulations. HFC-152a is inherently more energy efficient than HFC-134a and HFO-1234yf and in SL-MAC systems can generate cooling during deceleration, prolong comfort during idle stop (stop/start), and allow powered cooling at times when the engine can supply additional power with the lowest incremental fuel use. SL-MAC systems can also reduce the refrigerant charge, emissions, and service costs of HFO-1234yf.