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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.

In recent years, the push for reduced product development timelines has been more than ever with significant changes in the automotive market. High electrification, intelligent vehicle systems and increased number for car manufacturers are a few key drivers to the same. The front loading of development activities is now a key focus area for achieving faster product development. From vehicle dynamics point of view availability of subjective evaluation feedback plays a key role in optimization various system specifications. This paper discusses an approach for front loading through parallel development of the tire and vehicle chassis system, using advanced simulation and driving simulator technology. The proposed methodology uses virtual tire models which in combination with real-time vehicle model enables subjective evaluation of vehicle performance in driver-in-loop simulators.

Row-crop intercultural activities are widely affected by unavailability of manpower & seasonal nature. Current tractors with lower ground clearance are unable to access field after certain crop stage, may damage crop after certain growth. Some limited mechanization options available (self-propelled boom sprayer) are of higher cost. Crop care activities are intensive and observed consistent increase in cost. To address these challenges and unlock significant business benefits, a novel retro-fit height attachment for tractors has been developed. This attachment empowers tractors to access row-crop fields with crops standing at a height of up to 3 feet, effectively eliminating ground clearance constraints. The benefits of this innovative solution include enhanced accessibility, cost-effective mechanization, heightened operational efficiency, crop preservation, and improved sustainability.

The focus on driver and occupant safety as well as comfort is increasing rapidly while designing commercial vehicles in India. Improvements in the road network have enhanced road transport for commercial vehicles. Apart from the cost of operation and fuel economy, the commercial vehicles must deliver goods within stipulated time. These factors resulted in higher speed of operation for commercial vehicles. The design should not compromise the safety of the vehicle at these higher speeds of operation. The vehicle should obey the driver’s intended direction at all speeds and the response of the vehicle to driver input must be predictable without much larger surprises which can lead to accidents. The commercial vehicles are designed with rigid axle and RCB type steering system. This suspension and steering design combination introduce steering errors when vehicle travel over bump, braked and while cornering.

An agricultural tractor is often modified for special farming applications such as horticulture where the standard design is not suitable or accessible. In such cases, farm equipment manufacturers are demanded frugal and cost effect Engineered farming solutions. One such design is the innovative High Ground Clearance Tractor (HGCT) kit offered to increase the Tractor height without damaging the crop during farming operations. In this paper, the author proposes a durability assessment method to evaluate the HGCT kit attachments to meet the durability criteria. Road load data acquisition is done to measure the acceleration and strain levels for various horticulture operations such as tillage, spraying and transportation. Actual operating conditions are simulated with the help of four poster durability setups inside the lab which helps to reduce the field testing for design iterations.

The cost of fuels used for automobile are rising in India on account of high global crude oil prices. The fuel cost constitutes major portion of total cost of operation for Heavy commercial vehicles. Hence, the trend is to carry the goods transport through higher payload capacity rigid/straight trucks that offer lower transportation cost per unit of goods transported. This is driving the design of multi-axle heavy trucks that have lift axles. In addition, improved network of highways and road infrastructure is leading to increase in average operating speed of heavy commercial vehicles. It has made increased focus on occupant as well as road safety while designing the heavy trucks. Hence, the analysis of lift axle suspension from the point of view of vehicle handling and stability is essential. There are two basic kinds of lift axle designs used in heavy commercial vehicles: self-steered lift axle having single tire on each side and non-steered lift axle with dual tires on each side.

Closed crankcase ventilation prevent harmful gases from entering atmosphere thereby reducing hydrocarbon emissions. Ventilation system usually carries blowby gases along with oil mist generated from Engine to Air intake system. Major sources of blowby occurs from leak in combustion chamber through piston rings, leakage from turbocharger shafts & leakage from valve guides. Oil mist carried by these blowby gases gets separated using separation media before passing to Air Intake. Fleece separation media has high separation efficiency with lower pressure loss for oil aerosol particles having size above 10 microns. However, efficiency of fleece media drops drastically if size of aerosol particles are below 10 microns. Aerosol mist of lower particle size (>10 microns) generally forms due to flash boiling on piston under crown area and from shafts of turbo charger due to high speeds combined with elevated temperatures. High power density diesel engine is taken for our study.

In automotive world role of suspension system is to absorb vibrations from the road, and to provide stability while vehicle is going over bumps or uneven roads, cornering, acceleration and braking etc. For body on frame SUVs which are typically characterized by high center of gravity, it is quite critical to find best balance in ensuring stability of the vehicle and having comfortable ride performance. Rigid axle rear suspension is quite a typical choice in such vehicles, wherein lower and upper control links are two important components subjected to lateral, longitudinal, and vertical loads. These links allow the vehicle to move smoothly throughout the entire range of suspension travel. Kinematics and compliance optimization of these links is a major factor in definition of ride-handling performance of the vehicle.

Increased popularity on SUV category in the market has led to high focus on performance attributes of SUVs. Considering high weight & CoG achieving target handling performance is always a challenge. Static Wheel Alignment parameters, especially Camber have shown significant contribution in Handling attributes of vehicle. This paper presents an experimental study on change in wheel camber under the influence of different vehicle loading conditions. In SUVs, generally wheel is subjected to large deflection from its high static loads which makes it quite difficult to maintain an ideal camber angle. Hence, it is important to analyze the camber angle variations under actual loading conditions. An in-house fixture is developed to emulate the actual vehicle loading conditions at rear wheel end. The multi-link rigid axle suspension with watt’s link assembly is mounted on the chassis-frame which is rigidly fixed to ground, and loads are achieved through hydraulic actuators at Wheels.

Construction equipment off highway vehicles are heavy industry vehicles that run on diesel engines. To meet the emission norms, these engines have the Exhaust After Treatment System (EATS) which includes two primary subassemblies, i.e., a Diesel Oxidation Catalyst (DOC) subassembly to reduce the HC and CO emissions and a Selective catalytic Reduction (SCR) subassembly to reduce NOx emissions. Because of the excessive vibrations in the engine and continuous heavy-duty usage of the Construction equipment, any failures in the EATS system leading to escape of exhaust gas is a statuary non-compliance. Hence, understanding the effect of engine vibrations and proposing a cost-effective solution is paramount in designing the EATS system including the SCR assembly. A field-testing failure of an SCR assembly has been taken in consideration for this study.

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.

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.

Powertrain complexity rapidly increasing to meet fast moving regulation requirements. The BS6 Phase-1 regulation norms were implemented in India from April 1, 2020 and replaced the previous BS4 norms. Phase-2 of the BS6 regulation norms were came into effect on April 1, 2023. To meet this stringent regulation requirement, need effective performance of after treatment systems like DOC, DPF and SCR demands critical hardware selection and implementation. In Indian market, LCV application is cost sensitive and highly competitive where operational cost is most critical factor. Naturally aspirated engine has less operating cost, which is the best for LCV applications, but is has its own challenges to meet BS6 norms like higher engine out NOx, dynamic temperature profiles etc. A robust DeNOx emissions strategy is developed in naturally aspirated engine LCV application to meet cycle emissions, real drive emissions and OBD requirements.

Ethanol-gasoline blended fuels have been widely implemented in Indian markets followed by the Govt of India’s road map as ethanol reduces life-cycle greenhouse gas emissions and improves anti-knock performance. However, effects of Ethanol Blending on engine out emissions characteristics including particulates from gasoline direct injection (GDI) engine remains under development and investigation. In this study the effect of ethanol blended gasoline fuels with two blending rates 10% and 20% (v/v %) on catalyst conversion efficiencies and emissions on a 1.2 litre 3-cylinder turbo GDI engine is investigated. The addition of ethanol to gasoline fuel enhances the Octane rating (RON) of the blended fuels, oxygen content and changes Reid vapor pressure (RVP). The influence of lambda biasing, and lambda trim controller has been tested. The approach for calibration was adopted based on achieving the target pollutant conversion efficiencies.

BS6.1 emission standards were implemented in India in 2020 followed by BS6.2 which added more controls on emission limits. For BS6.2 OBD (On Board Diagnostics) and RDE (Real Driving Emission) were added on to the existing BS6.1 emissions. Emission control changes usually need addition of new parts, calibration changes and durability requirements. For the current 1.5L, 3-cylinder diesel engine an pSCR (Passive Selective Catalytic Reduction) brick was added for control of NOx for meeting RDE. For meeting OBD requirements PM (Particulate Matter) and NOx sensors were added in the cold end pipe along with calibration changes to meet the BS6.2 norms. In this paper we will discuss on the design aspects of sensors and pSCR only. The sensor and pSCR positioning plays vital role in meeting the legislative requirements and to ensure the ease of assembly and durability of the parts.

The purpose of this study is to conduct dynamic seat pressure mapping on vehicle seats during its operation on different test tracks under ambient environmental conditions for a defined speed. The test track comprises of pave roads, high frequency track, low frequency track and twist track. The variations in pressure distribution on seat during diverse road load inputs help to understand the seat cushion and back comfort for unique percentiles of human subjects ranging from 50th to 95th percentile population. For conducting the study, a sport utility vehicle (SUV) loaded with leatherette seats has chosen. Totally six participants (human subjects), five male and one female selected for the study based on their BMI (Body mass index) and body morphology. Pressure mats suitable for taking dynamic load inputs and able to log the data at a defined sampling rate mounted on seats and secured properly. The pressure mats should cover the seat cushion, bolster areas and back seat completely.

The implementation of TREM/CEV 5 emission norms on farm equipment will bring in cost pressure due to the need for exhaust after treatment systems. This cost increase needs to be reduced by bringing in more efficient and effective processes to shorten the development phase and to provide better fuel efficiencies. In this work ETAS ASCMO Online DoE with Constraint Modelling (ODCM) was applied to execute smart online DoE on a new common rail diesel engine with EGR, whose exact bounds of operation was not available. A Global test plan with ASCMO Static was created without much focus on detailed constraints of engine operation, other than the full load curve. The parameters which were selected were Speed, Torque, Rail Pressure, Main Timing, EGR Valve Position, Pilot Separation and Quantity and Post Quantity and Separation. For these parameters, the safe operating bounds were not available. This ASCMO Static test plan is automated and executed on engine test cell with ETAS INCAFlow.

Effective 1st April 2023, India's automotive emissions regulation has shifted from BS-VI Stage-1 to BS-VI Stage-2 standard the after-treatment systems need to demonstrate robust performance not just on the cycle, but also to demonstrate emissions for on-road Real Driving Emission (RDE) conditions. A stringent On-Board Diagnostics (OBD) strategy to monitor the real-time emission levels along with compliance Road Driving Emissions (RDEs) are focus areas for BS VI Stage-2 emission legislation. The maximum speed on MIDC is 90km/h in BS-VI Stage-1, Diesel Oxidation Catalyst (DOC)+Selective Catalyst Reduction Filter (SCRF®) was able to meet legislation at the lab, and now with the RDE cycle max speed of the vehicles under the M1 category <3.5 T will have the max permitted legal limit shall surpass 100 km/h for not around 3% of the span in the third phase of driving cycle for which max speed is up to 120 km/h.

Gears are one of the vital components to transmit torque efficiently. Helical gears are chosen as they transmit higher torque with lesser noise compared to spur gears of same size. All new age gearboxes require to transmit maximum torque with minimum packaging space available to improve torque density. Ways of reducing weight are using lesser density material, decreasing centre distance, and thereby reducing pitch circle diameter of all gears, etc. However, they will also affect torque carrying capacity of gearbox which can lead to gear failure in conventional transmission architecture gearboxes with input reduction method. In input reduction method, torque gets multiplied from input shaft to countershaft. Countershaft torque is multiplied to output shaft gears requiring higher torque capacity gears on output shaft. In this research, output shaft reduction architecture is proposed to avoid torque multiplication from input shaft to countershaft gears.

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.