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Emissions regulation continually drives the automotive industry to innovate and develop. This pushes to introduce mechanism to maintain negative crankcase pressure in gas engine to meet this changing regulation. The way a turbocharger is used, to meet engine performance, can impact the pressure balance over the compressor and turbine end seals. This pressure difference can allow oil to leak through turbocharger seals. In normal engine operating condition the pressure in the turbocharger end housings is higher than the bearing housing and oil/gas flows into the bearing housing, through the oil drain to the crankcase. Under certain operating conditions, such as low idle and motoring, this pressure difference can be reversed with a higher bearing housing pressure than the pressure behind the turbine wheel.

Diesel Exhaust Fluid (DEF) concentration monitoring is done to detect the concentration at which the emission thresholds are exceeded in BSVI engines [1]. This paper introduces a novel method to model the fault monitoring system with enable conditions designed to detect deterioration in DEF concentration, while reducing misdetection. This eliminates the need for dedicated sensor, reduces complexity, cost, and potential sensor-related failure modes. Traditionally, Diesel Exhaust Fluid quality sensors have been employed to measure the absolute concentration of Diesel Exhaust Fluid in the aqueous solution of urea [2]. This information is used to detect usage of poor quality DEF which results in increase in NOx emission beyond legal limits.

As part of transformation from BS4 to BS6 automobile emission standard in India, engine manufactures are focusing on continuous development of emission control technologies and suitable strategies. Exhaust tail pipe emission and Crankcase emission are added together to meet the regulation acceptable limit. The crankcase emissions contribute substantially to the total Particulate Matter (PM) emitted from an engine. Hence there is a need of design and development of suitable Crankcase ventilation system. This paper presents investigation of high PM contributed from Open Crankcase ventilation (OCV) system in Diesel engine and experiment based solutions.

Vehicular Emission testing is gaining importance over the past years in the wake of requirements for real driving emissions with implementation of RDE packages across Europe / USA and various developing countries. Extending the same concept for other countries poses slight challenges in terms of geographical and climatic conditions prevailing in the country, where the climatic conditions are differing from Europe / USA. It is a challenge to accept the same boundary conditions as in Europe, at the same time the challenge is to find a threshold number in a more scientific manner. This study concentrates on determination and recommendation of thresholds for ambient temperature and altitude. The basis for temperature threshold would be to determine the percentage of time the temperature exceeded beyond the threshold over year in the country. The basis for Altitude is considered based on the percentage of total length of roads beyond the threshold altitude limit.

In the emerging commercial vehicle sector, it is very essential to give a product to customer, which is very reliable and less prone to the failures to make the product successful in the market. In order to make it possible, the product is to be validated to replicate the exact field conditions, where it is going to be operated. Lab testing plays a vital role in reproducing the field conditions in order to reduce the lead time in overall product life cycle development process. This paper deals with the design and fabrication of the steering column slip endurance test rig. This rig is capable of generating wear on the steering column splines coating which predominantly leads to failure of steering column. The data acquired from Proving Ground (PG) was analyzed and block cycles were generated with help of data analyzing tools.

In the present scenario, delivering the right product at the right time is very crucial in automotive sector to grab the competitive advantage. In the development stage, validation process devours most of the product development time. This paper focuses on reducing the validation time for damper (shock absorber) variants which is a vital component in commercial vehicle suspension system. New test facility is designed for both performance test and endurance testing of six samples simultaneously. In addition, it provides force trend monitoring during the validation which increases the efficiency of test with an enhanced control system. This new facility is also designed to provide side loading capability for individual dampers in addition to the conventional axial loading. The key parameter during validation is control of damper seal temperature within the range of 70-90°C. A cooling circuit is designed to provide an efficient temperature control by re-circulating cold water.

In competitive vehicle market, the product must be designed and validated in shorter time span without compromising the quality. The durability of the vehicle is tested either by on road trials undertaken at the actual customer supplication sites for large time period or in the accelerated rough surfaces called “Proving ground” to validate in shorter time span. Accelerated proving ground durability testing plays a vital role in enabling shorter product development cycles by simulating the road load influences alone from the actual field conditions. It is imperative to simulate the test vehicle at proving ground (PG) testing such that it replicates the same damage that occurs in the field due to road loads. PG validation requires a specific durability test sequence for every segment of commercial vehicles due to different customer usage applications and terrain conditions. This diversity in applications and terrains induce structural damage at different range of frequencies.

Fuel economy is an important customer requirement which determines the position of earth-movers such as backhoe loaders in the market. Earth-movers are heavy duty machines that are used for construction works. Currently fuel consumption in earth-movers is quantified as fuel consumed per unit time (Liters per hour). Similarly, conventional measure of productivity of the earth-movers is in terms of volume of soil trenched per hour. Measurements using the above scales showed wide variations in measured fuel consumption and productivity, For the same equipment between measurements Two equipment of same make at different trench locations and Against the competitor equipment This inconsistency and lack of a proper measuring system made logical decision making extremely difficult. This paper describes the step by step procedures involved in deriving the methodology for robust fuel consumption measurement of earth-mover vehicles.

Off-road BS III CEV (US-TIER III equivalent) emission regulations for diesel engines (i.e. Construction Equipment Vehicles) in India demands a technology upgrade to achieve a large reduction in NOx (>50%) and Particulate Matter (>50%) compared to BS II CEV emission levels. EGR is a widely accepted technology for NOx reduction in off-road engines due to lower initial and operating costs. But EGR has its own inherent deficiency of poor thermal efficiency due to lack of oxygen and further increase in soot adding complexity of meeting PM Emissions. Hence an engine meeting BS III CEV norms without EGR/SCR technologies with low initial investment is most desired solution for Indian off-road segment. This work deals with the development of an off-road diesel engine rating from 56 to 74 kW, focused mainly on in-cylinder optimization with the aid of optimum injection and charging strategies.

This study deals with the development of an internal EGR (Exhaust Gas Recirculation) system for NOx reduction on a six cylinder, turbocharged intercooled, off-road diesel engine based on a modified cam with secondary lift. One dimensional thermodynamic simulation model was developed using a commercially available code. MCC heat release model was refined in the present work by considering wall impingement of the fuel as given by Lakshminarayanan et al. The NOx prediction accuracy was improved to a level of 90% by a generic polynomial fit between air excess ratio and prediction constants. Simulation results of base model were correlating to more than 95% with experimental results for ISO 8178 C1 test cycle. Parametric study of intake and exhaust valve events was conducted with 2IVO (Secondary Intake Valve Opening) and 2EVO (Secondary Exhaust Valve Opening) methods. Combinations of different opening angles and lifts were chosen in both 2IVO and 2EVO methods for the study.

Ashok Leyland, India had commissioned a web portal towards serving their end customers with better fleet management. The services offered through this portal helps in improving the productivity and safety of vehicles, business operations and hence, the profitability of the customers. Track and trace, SMS/email alerts and report generation are the major functionalities of this portal. They assist the customers in analyzing the operations of their vehicles and take corrective actions towards optimizing them. However, there were certain problems faced by the customers, while accessing these functionalities through the web portal. This includes, significantly high lead time taken for report generation, unavailability of location details in the reports and track page due to early expiry of reverse geo-coding service limits.

Multi Body Dynamics (MBD) simulation software is used in product development cycle to reduce the lead time to market. These software have standard parametric templates for modeling metallic suspension systems, which can be quickly modified and used in full vehicle models for ride, handling analysis and the durability load predictions. Generally every Original Equipment Manufacturer (OEM) has unique air suspension arrangement and hence standard template is not available for air suspension modeling in commercial MBD software. Air suspension with self-leveling control mechanism is preferred over metallic suspension in the commercial passenger vehicle like bus for smooth ride comfort. Hence custom made templates for these systems need to be developed for use with MBD software. In this paper, a simplified model of air suspension is presented.

In the present work, a 4 cylinder, 5.3 liter, Direct Injection Diesel engine producing 140 kW rated power was upgraded to a higher power rating of 170 kW complying with Euro V emission norm. The exhaust after treatment strategy was changed from Exhaust Gas Recirculation (EGR) to Selective Catalytic Reduction (SCR). 1-D thermodynamic simulation was used to simulate the performance. The simulation model was calibrated for performance parameters with the test results available from the 140 kW engine. This model was used to carry out the turbocharger matching for the 170 kW engine using the Simplified and Full Turbocharger model. A parametric study was carried out for the variables like Compression ratio, Start of Combustion shift and Compressor pressure ratio in view of the target Brake Specific Fuel Consumption (BSFC) and Peak firing pressure limits. The finalized model parameters were used for carrying out a Full throttle and Part throttle performance at selected operating points.

Exhaust Gas Recirculation (EGR) is a method to control Nitrogen Oxide (NOx) emissions from automobile exhaust. In this method, small amount of the exhaust gas is recirculated into the combustion chamber through the air intake system. The exhaust gas is mixed with charge air just before entering intake manifold. Appropriate mixing of exhaust gas with charge air is necessary to ensure nearly equal amount of exhaust gas flow into all the cylinders. Present research efforts by various automobile manufacturers rely on commercial CFD simulation tools to identify and resolve flow and thermal issues occurring in various vehicle systems. The focus of this paper is to optimize the EGR system to obtain uniform distribution of recirculated exhaust gas to every cylinder of a six cylinder heavy duty diesel engine. CFD simulations were done for this engine using a commercial CFD solver. Mixing and transport of the two fluids was modeled using species transport approach.