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Over the ages of automotive history, expectations of the customers increases vastly starting from driving comfort, better fuel economy and a safe vehicle. Requirement of good vehicle drivability from customers are increasing without any compromise of fuel economy and vehicle features. To enhance the product, it is a must for every OEM’s to have better drivability to fulfill the needs of the customer. This paper explains Objective Drivability Evaluation done on compact SUV vehicle and comparison with subjective drivability. Vehicle manufacturer usually evaluate drivability based on the subjective assessments of experienced test drivers with a sequence of certain maneuvers. In this study, we have used the objective drivability assessment tool AVL drive to obtain the vehicle drivability rating. The vehicle inputs from the accelerometer sensor which captures the longitudinal acceleration and CAN bus signals such as engine speed, vehicle speed, accelerator pedal, are fed into the software.

Each OEM has a distinguishing drivability character that defines its image in the market to achieve brand differentiation. Drivability is one of the important factors along with fuel economy that determines the success of a vehicle vis-à-vis its competitors. It can be said that the need for good drivability among customers is increasing day by day similar to the need for high fuel economy. Drivability is the response that a vehicle delivers to the inputs of the driver which are mainly accelerator, brake, clutch, gear and steering. The dynamic response of the vehicle is mainly in terms of velocity and acceleration. The way the response is delivered will characterize the drivability of a vehicle. The drivability event discussed in this paper is throttle tip-in response which is one of the critical evaluation factors for defining the character of a Sports Utility Vehicle.

Diesel engines are primarily being used for Power Generation due to its higher thermal efficiency and its superior fuel consumption compared to gasoline engines. Due to the growing awareness of environment protection and producing eco-friendly products, government agencies throughout the world have started introducing legislations which would limit the emissions produced by engines and would help in resolving the cause for cleaner and greener environment. In similar lines, Central Pollution Control Board (CPCB) has proposed to introduce the next stage of stringent emission norms for engines used in Power Generation by April 2014 which are comparable to the best in the world. This paper deals with the strategies applied and experimental results for meeting the proposed CPCB-II norms.

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.

The present work describes an approach to predict the vehicle fuel economy by simulating its engine drive cycle on a transient engine dynamometer in an engine testbed. The driving cycles investigated in the current study were generated from the typical experimental data measured on different vehicles ranging from Intermediate Commercial Vehicle (ICV) to Heavy-duty Commercial Vehicle (HCV) in real-world traffic conditions include various cities, highways and village roads in India. Reliability and robustness of the method was studied on various engines with cubic capacity from 3.8 liters to 8 liters using different drive cycles, and the results were discussed. Later, using same measured drive cycles, vehicle fuel economy was predicted by a vehicle simulation tool (AVL CRUISE) and results were compared with experimental data. In addition, engine coolant temperature effect on fuel economy was investigated.