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Automobile OEM's around the world are looking to improve their overall vehicle and engine efficiency in terms of fuel economy and power output. Efficiency improvement is possible by cutting down the engine parasitic loads. One such parasitic load is the oil pump, which lubricates the engine parts. Oil pump is the heart of an engine lubrication system, and its important functions are cooling and lubricating the engine moving parts by delivering adequate oil flow based on the engine demand. Insufficient or no oil delivery from the oil pump leads to the seizure of the engine. The internal vane type oil pump is one kind of positive displacement type pump, where oil gets transferred from the oil sump into the inlet volume. The negative pressure is created inside the pumping chamber due to increase in area. As the vane rotates eccentrically with respect to the stator, it delivers the oil at a higher pressure from inlet to outlet and supplies to engine gallery through the discharge port.

The reduction of development time of new Internal Combustion Engines prototype and reduction of fuel consumption are key issues in automotive Industry. Lubricating oil pump systems having potential of reducing fuel consumption by up to 3% in the new European Motor Vehicle Emission Group (MVEG) Cycle. Oil pump feeds lubricant oil into the parts of engine to prevent wear and to cool the moving parts of the engine. Gerotor pump is a special kind of internal rotary positive displacement pump which is driven by crank shaft. It provides high volumetric efficiency and smooth pumping action, and it works well with a wide range of fluid viscosities. Tip to tip clearance, volumetric efficiency, flow ripple and cavitation damage are causes for concern in Gerotor pump with high output flow. To optimize the pump performance, it is essential to understand the flow dynamics inside the pump.

Emission standards have been one of the driving forces behind many of the technological changes in the automotive industry. Crankcase breathing of engine is necessary in order to prevent build up of pressure and explosions due to leakage of combustion gas past the piston rings. Breathing means admitting outside air when the pistons move up creating a partial vacuum in the crankcase and releasing the gas when the pistons move down pressurising the crankcase. The gases let out will consist mostly of hydrocarbons. 20% of the total hydrocarbons emitted in a passenger car is due to crankcase gases. By introducing the Positive Crankcase Ventilation system, which is essentially sealing the crankcase and allowing the gas through the engine to be burnt off, the hydrocarbon emissions due to crankcase breathing is totally eliminated. Positive Crankcase Ventilation (PCV) system using variable flow PCV valve is used in most of the automobile gasoline engine applications.

Carburetors are widely used for two wheeler applications in India as well as countries like Taiwan, Indonesia and China. These carburetors are characterized by simple design and low cost. As the emission norms are becoming more and more stringent, matching the carburetors for vehicle application becomes very challenging. Earlier it was widely believed that, for meeting the Euro-3 regulations, even two wheelers with small engine capacity had to employ electronic fuel injection. However, many vehicle manufacturers have successfully developed carburetors for meeting Euro-3 norms by employing catalytic converters without any electronic control. This development has been essentially motivated by the need for low cost. Flow variation is inherent in mass produced carburetors because there are many parts, which contribute to the air-fuel ratio delivered by the carburetor. Carburetors with the mixture control pilot systems were mass-produced and compared for results with air control system.

The simple design and low cost of the carburator makes it an attractive proposition to be used for two-wheeler applications in India and other countries. However, stringent emission standards pose greater challenge in carburator matching for different vehicle applications. The use of electronics for controlling the air-fuel ratio in a carburator with closed-loop control to meet Euro-III standards is the driving force to undertake this project. The goal is to achieve the best catalytic converter efficiency when the air-fuel-ratio is maintained at stoichiometric within a close band. Inherent variations in manufacturing of carburators can cause the air-fuel ratio to drift from stoichiometric and have an adverse effect on catalytic converter efficiency. The most efficient method of maintaining air-fuel ratio within a close band near stoichiometric is through closed-loop control. This method is widely used in passenger cars with fuel injection.

Carburettors are widely used for control of Air/fuel mixture in 2/3 wheeler vehicles in India as well as other countries. Carburettor technology has improved over the years to meet stringent emission requirements as well as fuel economy demands of customer. With the introduction of Euro-III regulations in 2006 and proposed BS IV requirements in India, emphasis is laid on the transient control capability of carburettor. A project was undertaken at Ucal Fuel Systems to understand the transient characteristics of carburettor and develop electronic control to achieve programmable control of Air/Fuel ratio on the driving cycle. Several tests were conducted on carburettor flow test bench and on chassis dynamometer to understand the transient control response and develop control strategy. It is observed that the Air/fuel ratio measured at steady speed trials, have a marked influence on the transient Air/Fuel ratio behavior as measured on drive cycles.

The need to control the emissions from two wheelers is well-known. India is the second largest producer of two wheelers in the world next only to China. The two wheelers are powered by either two stroke or four stroke engines. The two stroke engines though simple in design has the drawback of high exhaust emissions and poor fuel economy. The four stroke engines on the other hand have much more moving parts but they have the advantages of lesser exhaust emissions and better fuel economy. The mechanism of pollutant formation in S.I. Engines is briefly explained and the logical evolution of control techniques is discussed in this paper.

Year 2000 emission norms for Indian passenger cars, which have been notified requires major changes in the existing technologies being used in the passenger car vehicles on roads. Electronic fuel injection systems and catalytic converters are being used extensively abroad to meet stringent emission regulations. Even in India, major joint ventures in passenger car segment have introduced vehicles with single-point / multi-point fuel injection systems. It has become difficult to meet the mandated emission regulations with the conventional mechanical carburetted vehicles. Automotive Research Association of India alongwith M/s UCAL Fuel Systems has developed an electronic feedback carburettor system to use alongwith catalytic converter for a passenger car to meet the year 2000 emission norms. A closed loop system has been designed and developed which takes the input from a λ-sensor output and controls the additional air added in the intake manifold of the engine through a stepper motor.

A novel Air-Alcohol INDUCTOR with an inherent flexibility to tailor the alcohol flow rate, has been developed for a multi-cylinder, variable-speed, vehicular Diesel engine to enable operation in the Alcohol-Diesel bi-fuel mode. Tests have been carried out on the dynamometer over the whole speed range of the engine. Also road tests have been carried out under constant vehicular speed conditions. Upto 48% Diesel substitution was achieved on road without reduction in thermal efficiency. Laboratory tests indicate lower exhaust temperatures and lower smoke intensities than in the diesel mode.