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In this study, 3D air-flow-field evolution in a single cylinder optical research engine was determined using tomographic particle imaging velocimetry (TPIV) at different engine speeds. Two directional projections of captured flow-field were pre-processed to reconstruct the 3D flow-field by using the MART (multiplicative algebraic reconstruction technique) algorithm. Ensemble average flow pattern was used to investigate the air-flow behavior inside the combustion chamber during the intake and compression strokes of an engine cycle. In-cylinder air-flow characteristics were significantly affected by the engine speed. Experimental results showed that high velocities generated during the first half of the intake stroke dissipated in later stages of the intake stroke. In-cylinder flow visualization indicated that large part of flow energy dissipated during the intake stroke and energy dissipation was the maximum near the end of the intake stroke.

Condensed soot coming out of vehicular exhaust is commonly classified as organic carbon (OC) and elemental carbon (EC). OC can be directly emitted to the atmosphere in the particulate form (primary carbon) from the tailpipe or can be produced by gas-to-particle conversion process (secondary organic carbon, SOC). Under typical atmospheric dilution conditions, most of the semi-volatile material is present in the form of soot. SOC holds wider implications in terms of their adverse health and climate impact. Diesel exhaust is environmentally reactive and it has long been understood that the ambient interaction of exhaust hydrocarbons and NOx results in the formation of ozone and other potentially toxic secondary organic carbon species. The current emission norms look at the primary emissions from the engine exhaust. Also, research efforts are geared towards controlling the emissions of primary carbon.

Petroleum products are used to power internal combustion engines (ICEs). Emissions and depletion of petroleum reserves are important questions that need to be answered to ensure existence of ICEs. Indian Railways (IR) operates diesel locomotives, which emit large volume of pollutants into the environment. IR is looking for an alternative to diesel for powering the Locomotives. Methanol has emerged as a replacement for petroleum fuels because it can be produced from renewable resources as well as from non-renewable resources in large quantities on a commercially viable scale. It has similar/superior physico-chemical properties, which reduce tailpipe emissions significantly. It is therefore necessary to understand the in-cylinder phenomenon in methanol fueled engines before its implementation on a large-scale.

The interface between the piston rings and cylinder liner play an important role in total frictional losses and mechanical wear of internal combustion engine and is increasingly coming under scrutiny as legislated particulate emission standards are getting more and more stringent. The capacitance method is used for measurement of minimum oil film thickness between piston ring and liner interface. Measurement of capacitance formed between the piston ring and a probe mounted flush in the liner provides an accurate means of determining the oil film thickness provided that the region between the probe and liner is flooded with oil and dielectric constant of the oil is known. This paper presents detailed design and measurement of lubricating oil film thickness using capacitive micro sensor in a non-firing engine simulator. Lubricating oil film thickness was found to vary between 0.2μm to 8μm in the non firing engine simulator.

Biodiesel is being explored as a sustainable renewable fuel for vehicles in India due to mounting foreign exchange expenditure to import crude petroleum. Significant amount of research and development work is being undertaken in India to investigate various aspects of biodiesel utilisation in different types of engines. This study is an effort to jointly investigate the use of biodiesel (B100) in an unmodified BS-III compliant sports utility vehicle (SUV) by a consortium of academia (IIT Kanpur) and Industry (M&M) to realistically assess whether biodiesel is compatible with modern engine technology vehicles. Two identical vehicles were operated in tandem using biodiesel (B100) and mineral diesel (B00) respectively for 30,000 kilometers in field conditions. The lubricating oil samples were collected and detailed analysis for assessing the comparative effect of new fuel (B100) vis-à-vis mineral diesel was carried out.

Biodiesel is mono alkyl ester derived from vegetable oils through transesterification reaction and can be used as an alternative to mineral diesel. In the present research, methyl ester of rice-bran oil (ROME) is produced through transesterification of rice-bran oil using methanol in presence of sodium hydroxide (NaOH) catalyst. Various properties like viscosity, density, flash point, calorific value of the biodiesel thus prepared are characterized and found comparable to diesel. On the basis of previous research for performance, emission and combustion characteristics, a 20% blend of ROME (B20) was selected as optimum biodiesel blend for endurance test. Endurance test of 100 hours was conducted on a medium duty direct injection transportation diesel engine. Tests were conducted under predetermined loading cycles in two phases: engine operating on mineral diesel and engine fuelled with 20% biodiesel blend.

The development of vehicles continues to be determined by increasingly stringent emissions standards including CO2 emissions and fuel consumption. To fulfill the simultaneous emission requirements for near zero pollutant and low CO2 levels, which are the challenges of future powertrains, many research studies are currently being carried out world over on new engine combustion process, such as Controlled Auto Ignition (CAI) for gasoline engines and Homogeneous Charge Compression Ignition (HCCI) for diesel engines. In HCCI combustion engine, ignition timing and combustion rates are dominated by physical and chemical properties of fuel/air/residual gas mixtures, boundary conditions including ambient temperature, pressure, and humidity and engine operating conditions such as load, speed etc.

This study was set out to characterize particulate emissions from diesel engines in terms of poly aromatic hydrocarbon emissions and Benzene Soluble Organic Fraction. The characteristics of DPM vary with engine operating conditions, quality of fuel and lubricants being used. Hence the diesel exhaust for the purpose of toxicity characterization needs to be studied for Organic Matter in terms of Poly Aromatic Hydrocarbon (PAH) and Benzene Soluble Fraction (BSF). Therefore, the objectives of the present research are to characterize the diesel exhaust particulate matter for the above parameters under varying engine operating conditions/loads. Six PAHs, namely Chrysene, Benzo (k) Flouranthene, Benzo (a) Pyrene, Dibenzo (a, h) Anthracene, Benzo (g,h,i) Perylene and Indenopyrene were analyzed on High Pressure Liquid Chromatography (HPLC). PAH concentrations in the particulates of Mahindra DI engine were affected by engine loads.

Indian Railways have a fleet of high-horsepower diesel-electric locomotives rated at 2310 kW. These high horsepower diesel-electric locomotives have evolved from original design of 1940 kW locomotives. Adoption of new design turbochargers was essential for this upgrading efforts and a series of new design turbochargers were evaluated on the engine test-bed before their use on the diesel locomotives. The objective was to increase engine power output, improve fuel efficiency and limit thermal loading. Test-bed evaluation of different turbochargers was carried out for comparing five different turbochargers. Each turbocharger had different size nozzle ring, diffuser, turbine blade assembly, impeller and inducer. The compressor maps of turbochargers were used to plot the engine load lines and to calculate surge margins. The tests involved measuring critical parameters for various combinations of engine speed and load for every turbocharger.