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In today’s automobile industry where BS6 emission is posing a high challenge for aggregate development, cost control and with limited timeline. The main target is to provide the cooling system to have less impact on the in terms of cost, weight and to meet the challenging engineering requirement. Thus, the frugal engineering comes into the picture. This paper shows the application of thermosyphon principle for UDM injector cooling thereby reducing the rotation parts and power consumption such as an electric pump. Thermosyphon is a method of passive heat exchange and is based on natural convection, which circulates a fluid without the necessity of a mechanical or electric pump. The natural convection of the liquid commences when heat transfer to the liquid gives rise to a temperature difference from one side of the loop to the other.

Turbocharged common rail direct injection engines offer multiple benefits compared to their naturally aspirated counterparts by allowing for a significant increase in the power and torque output, while simultaneously improving the specific fuel consumption and smoke. They also make it possible for the engine to operate at a leaner air/fuel mixture ratio, thereby reducing particulate matter emission and permitting higher EGR flow rates. In the present work, a two cylinder, naturally aspirated common rail injected engine for use on a load carrier platform has been fitted with a turbocharger for improving the power and torque output, so that the engine can be used in a vehicle with a higher kerb weight. The basic architecture and hardware remain unchanged between the naturally aspirated and turbocharged versions. A fixed geometry, waste gated turbocharger with intercooling is used.

This study on optimum magnification at which Retained austenite to be evaluated by comparing the difference in determining the retained austenite in low carbon carburizing alloy steel using the optical metallurgical micrographic method and X-ray diffraction method. The retained austenite phase will be in surface and color is white in nature also its presented in between the martensite needles. It can be distinguished as separate micro-constituents by using image analyzing software. In another method the RA measurements were carried out on the surface by PROTO iXRD Retained austenite measuring system using Cr K radiation. The (211) and (200) reflections of Martensite and (220) and (200) reflections of Austenite were made for this estimation. However, the calculated values of retained austenite by metallurgical microscope in different magnifications are not identical.

The automobile industry is going through one of the most challenging times, with increased competition in the market which is enforcing competitive prices of the products along with meeting the stringent emission norms. One such requirement for BS6 phase 2 emission norms is monitoring for partial failure of the component if the tailpipe emissions are higher than the OBD limits. Recently PM (soot) sensor is employed for partial failure monitoring of DPF in diesel passenger cars.. PM sensor detects soot leakage in case of DPF substrate failure. There is a cost factor along with extensive calibration efforts which are needed to ensure sensor works flawlessly. This paper deals with the development of an algorithm with which robust detection of DPF substrate failure is achieved without addition of any sensor in the aftertreatment system.

In this paper, Authors tried to investigate the influence of Low Temperature EGR (LtEGR) on NOx, PM emissions and fuel efficiency in NEDC 120 cycle. Sports Utility Vehicle (SUV) less than 3.5T vehicle selected for investigation of LtEGR. The existing water cooling circuit modified to suitable to handle the LtEGR concept without changing the existing EGR cooler. Cooled EGR technology has two benefits in terms of handling high EGR ratios and more fresh air within the engine displacement. Under this assumption separate LtEGR layout was prepared for the evolution of superior EGR cooling technologies and low pressure EGR.

The BS6 norms (phase 1) were implemented in India from April 1, 2020 and replaced the previous BS4 norms. Phase 2 of the BS6 norms, which came into effect on April 1, 2023. In accordance with the regulation requirement, effective performance of after treatment systems like DPF and SCR demands critical hardware implementation and robust monitoring strategies in the extended operating zone. Effective OBD monitoring of DPF, which is common to all BSVI certified vehicles, such that the defined strategy detects the presence or absence of the component is imperative. A robust monitoring strategy is developed to detect the presence of the DPF in the real world incorporating the worst possible driving conditions including idling, and irrespective of other environmental factors subject to a location or terrain. The differential pressure sensor across the DPF is used to study the actual pressure drop across the DPF.

In recent time, with inception of BS VI emission regulation with more focus on fuel economy and emission, many engine parts which were conventionally made from metal are getting replaced with plastic components for reducing weight to attain better fuel economy. EGR is commonly used technique to reduce emissions in diesel engine along with after treatment devices. EGR reduces peak combustion temperature inside the combustion chamber thereby reducing NOx. EGR is bypassed from the exhaust manifold, cooled down in EGR cooler and mixed with intake air at upstream of the intake manifold. Throttle valve is used for controlling the charged air flow to cylinders for different vehicle operating conditions. With compact engine layout EGR mixer are often located near to throttle valve thereby increasing the possibility of soot deposition on throttle valve.

Attaining better acoustic performance and back-pressure is a continuous research area in the design and development of passenger vehicle exhaust system. Design parameters such as tail pipe, resonator, internal pipes and baffles, muffler dimensions, number of flow reversals, perforated holes size and number etc. govern the muffler design. However, the analysis on the flow directivity from tail pipe is limited. A case study is demonstrated in this work on the development of automotive muffler with due consideration of back pressure and flow directivity from tail pipe. CFD methodology is engaged to evaluate the back pressure of different muffler configurations. The experimental and numerical results of backpressure have been validated. The numerical results are in close agreement with experimental results.

This paper deals with new trends in materials & heat treatment in automotive transmission shafting. The material is S48C a low carbon alloy steel and material for automotive shaft special significance as it reduces overall cost in vehicle transmission shafts. Conventional method of shaft heat heat-treatment is case hardening for 20MnCr5. S48C is low-carbon alloy steel. This is an alternate proposal to 20MnCr5.There are lot of advantages in induction hardening over case hardening. Also induction hardening process with S48C material becomes cheaper than case-hardening with 20MnCr5.Strength and resistance to stress must therefore be carefully considered during the material selection and heat-treatment process. We have done Static torsion test for 20MnCr5 (case hardened steel) and S48C (induction hardened shaft). Test results were comparable with 20MnCr5 (case hardened steel). Also after test a metallurgical inspection was done on an S48C (induction hardened shaft).

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.

Lubrication systems play a major role not only in the durability of modern IC engines but also in performance and emissions. The design of the lubrication system influences the brake thermal efficiency of the engine. Also, efficient lubrication reduces the engine's CO2 emissions significantly. Thus, it is critical for an IC engine to have a well-designed lubrication system that performs efficiently at all engine operating conditions. The conventional lubrication system has a fixed-displacement oil pump that can cater to a particular speed range. However, a fully variable displacement oil pump can cater to a wide range of speeds, thereby enhancing the engine fuel efficiency as the oil flow rates can be controlled precisely based on the engine speed and load conditions. This paper primarily discusses the optimization of a lubrication system with a Variable Displacement Oil Pump (VDOP) and a map-controlled Piston Cooling Jet (PCJ) for a passenger car diesel engine.

Stringent emission legislations increase the significance of emission reduction through crankcase ventilation systems in combustion engines. Oil mist separation efficiency of the CCV systems directly impacts the emissions of diesel engines. The CCV systems retain the oil with soot and carbon particles and return them to the oil sump. CCV thus reduces engine oil consumption and emissions. Contemporary technology enables usage of highly efficient CCV systems. However, the filtration efficiency of the CCV system is limited to keep crankcase pressure under limits. Oil particles which escape from CCV system result in soot deposit on turbocharger compressor leading to deterioration of turbocharger performance. Performance variation of turbocharger has a substantial impact on engine emissions. Therefore, it is essential to understand the effect of CCV system design and different engine operating conditions which accelerate the Oil mist deposits on turbocharger Compressor.

Tractors in the field are exposed to adverse operating conditions and are surrounded by dust and dirt. The tiny, thin and sharp broken straw and husks surround the system in reaper operation. The tractors which are equipped with air conditioning system tend to show detrimental effects in cooling performance. The compressor trips frequently by excess pressure developed in the system due to condenser clogging and hence cooling performance is reduced considerably. The air conditioning performance reduces due to the clogged condenser located on the top roof compartment of operator’s cabin, which is better design than keeping in front of radiator where clogging happens every hour and customer need to stop the tractor to clean it with specific blower.

As the FTP-75 drive cycle does not have a prescribed gear shift pattern, automotive OEMs have the flexibility to design. Conventionally, gear shift pattern was formulated based on trial and error method, typically with 10 to 12 iterations on chassis dynamometer. It was a time consuming (i.e. ~ 3 to 4 months) and expensive process. This approach led to declaring poor fuel economy (FE). A simulation procedure was required to generate a gear shift pattern that gives optimal trade-off amongst conflicting objectives (FE, performance and emissions). As a result, a simulation tool was developed in MATLAB to generate an optimum gear shift pattern. Three different SUV/UV models were used as test vehicles in this study. Chassis dyno testing was conducted, and data was collected using the base and optimized gear shift patterns. Dyno test results with optimized gear shift pattern showed FE improvement of ~ 4 to 5% while retaining the NOx margin well above engineering targets.

Increasing of automatic transmissions in passenger cars is based on pleasure of driving, smooth acceleration and easy operation makes the customer satisfaction. Challenges beyond 2020 is BS VI emission norms in India - a very tough goals on CO2& NOx reduction in Gasoline & Diesel vehicles. But its setback in lower fuel economy. To support & enhance fuel economy in Automatic transmissions as part of drivetrain technologies, this article discusses about the power losses in torque converters and experiments on the actual Automatic transmission (AT) vehicle on-road to understand the real city driving behavior in the aspects of gear utilization & gas pedal utilization throughout the entire traffic conditions. With that data research, slip area and slipping conditions is determined & clutch slip control is enabled at area in torque converter by ensuring that NVH parameters are not affected.

The given paper presents the main elements of frictional power loss distribution in an automotive axle for passenger car. For reference two different axles were compared of two different sizes to understand the impact of size and ratio of gear and bearings on power loss characteristics. It was observed that ~50% of total axle power loss is because of pinion head-tail bearing and its seals, which is very significant. Roughly 30% of total power loss is contributed by pinion-ring gear pair and differential bearings and remaining ~20% by wheel end bearing and seals. With this study the automotive companies can take note of the area where they need to focus more to reduce their CO2 emissions to meet the stringent BS6, CAFÉ and RDE emission norms.

With the implementation of stringent PM emission norms in various countries for diesel vehicles, the legislation demands a PM mass limit as low as 4.5mg/km in the NEDC cycle, starting from Euro5. This makes the usage of Diesel particulate filters (DPF) mandatory. The same is going to be mandated for upcoming BSV emission norms in India. Thus it becomes imperative to know the functional aspects of a DPF and their impacts. Basically there are two major functions of a DPF- Soot mass estimation and Soot burning or Regeneration. This paper highlights usage of DPF in Indian context from the perspective of one of the major aspects of DPF regeneration-Regeneration Interval, which is basically governed by vehicle/engine out smoke. Regeneration interval also has direct or indirect influence on life of engine of a vehicle and average fuel economy of a vehicle which will also be touched upon herein.

In recent times diesel powered vehicles are becoming popular due to improved performance and reduced exhaust emission with this the market share of diesel passenger cars expected to approach 60 % over the next few years. In compliance with future emission standards for diesel powered vehicles, it is required to use diesel particulate filters (DPF) along with other exhaust emission control devices. There is a need for more optimized DPF cell structure to collect maximum soot load with low pressure drop and improved exhaust performance from diesel vehicles in Indian driving conditions. In this thesis paper a detailed parametric study have been carried out on different DPF cell structures like Square, Hexagonal and combined cell geometry. The performances of different cell structure has been evaluated for maximum soot loading capacity and regeneration rate, pressure drop, temperature distribution across cell structure.

As the emission targets are getting tighter, efforts are made to improve the emission by all possible means. This work emphasis the potential of intercooler to reduce exhaust gas emissions (CO, HC, NOx and PM). A detailed analysis of experimental results on emissions is presented. The effect of intercooler efficiency on emissions is explained. A multi-utility vehicle equipped with common rail diesel engine was tested in NEDC cycle in chassis dynamometer. Ideally the vehicle emission lab should replicate a flat straight road condition & natural airflow. To obtain the airflow a variable velocity fan is used. The velocity of air emerging from the fan and relative position of the fan with vehicle has a significant role in intercooler efficiency and hence on emissions. This work explains the exercise carried out to correlate the intercooler efficiency and exhaust emissions with fan position and velocity.

For meeting upcoming BS IV & BS V emission norms in Heavy Commercial Vehicles, most of the manufacturers are taking SCR after treatment route. Though SCR system is more complex and involves higher cost impact, an optimized SCR system can bring down the payback period to about one year due to improved fuel economy. For development of an SCR after treatment system, selection of a correct SCR catalyst and its position in the system is very important. NOX conversion efficiency of catalyst depends on exhaust gas temperature at the catalyst and the velocity distribution over the face of the catalyst. Generally catalysts are evaluated for the conversion efficiency in engine test bed. In a drive to have a first-time-right solution, a CFD analysis was carried out considering the low and high flow rate conditions. CFD simulation models and the corresponding results were used as a predictive tool in the exhaust system development process.