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In general the mechanical design and function of synchronized manual transmissions has remained relatively constant over the years, with incremental improvements in components, gears, bearings, seals, synchronizers and fluids continuing to advance the quality of the overall product. Marketplace demands generally drive improvements which are primarily aimed at durability and shift quality. Recently, however, advances in control and actuation technology have led to a new generation of automated manual transmissions. As a result, compatibility with electronic and valve components is becoming increasingly important. The synchronizers and fluid are two components that can affect the overall transmission performance experienced by the end user. Historically, there has been a variety of synchronizer materials, primarily brass for smaller vehicles such as passenger cars and molybdenum-based products for larger commercial vehicles.

Application of Diesel Particulate Filter (DPF) will become necessary for trapping diesel particulate matter especially with stringent Emission Legislation of Euro IV and beyond. While developing a DPF, conflicting requirements like low-pressure drop, high thermal durability, high compressive strength, high trapping efficiency and practical regeneration needs to be considered. This paper focuses on the development and optimization of cost effective ceramic based DPFs for a diesel utility vehicle. The effect of DPF diameter, length, cell density and wall thickness on the pressure drop in fresh as well as soot laden conditions are evaluated, based on which the final size of DPF is determined. Special attention to substrate making, coating, canning, temperature and pressure feedback is given. Strategies for DPF regeneration like catalyzed and additive regeneration are evaluated.

In an earlier paper[1] we had emphasized the need for diesel engine lubricants meeting specific built-in specifications to combat the stress emanating out of the geographical, operational and engine design requirements in Indian subcontinent for heavy duty sectors. In this paper we present our work in identical domains for a segment utilizing passenger car and/or utility vehicles. This paper presents our work on development of a diesel engine oil to meet the specific requirements of a thermally-stressed IDI engine with respect to key performance attributes. The laboratory optimization for thermo-oxidative stability typical of requirements for IDI engines coupled with higher level of dispersancy and wear inhibition that are identified with current generation lube oils have further been established in engine test programs. The superior performance has been established in endurance test on a representative engine.

An experimental study was conducted on 2-stroke/4-stroke two-wheelers and a carburetted passenger car for engine-out benzene emissions from the in-use Indian vehicles, with and without a catalytic converter. The leaded gasoline, used for the study, was having 1.1 % vol. benzene and 16.6 % vol. total aromatics whereas unleaded gasoline was having 2.2 % vol. benzene and 35.2 % vol. total aromatics. Engine-out benzene was found to be linearly related to both, benzene and total aromatics content in the gasoline. Effectiveness of catalytic converter for conversion of the engine-out benzene was also studied. For two-wheelers, the concentration of engine-out benzene seems to be dependent upon the engine type i.e. 2/4-stroke engine and on conversion efficiency of the catalytic converters.

The preignition processes in a dual fuel engine are described and the roles of the formation and consumption of formaldehyde in these and subsequent processes are discussed. Reference is made to the results of detailed chemical kinetic modelling of the oxidation reactions of the gaseous fuel component during the compression stage. This is supported by experimental evidence of the kinetic role of formaldehyde through its deliberate induction with the intake charge of a dual fuel engine over a range of operating conditions and fuels. It is suggested that the preignition reaction activity of the gaseous fuel-air charge during compression contributes significantly to the observed extension of the ignition delay in dual fuel engines at very low load conditions when relatively small gaseous fuel concentrations are being used.