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In this ever-changing field of automotive industry where there is high competition to seek a place in market, it is necessary to design and develop products with a minimum lead time meeting the target specifications. This is normally achieved through product variants specific to customer requirements from the repository of design base created. Design bases are created based on the previous products and by bench marking. Vacuum Pump is an engine driven part identified for this study. The main aim of this study is to create a mathematical model, and use Artificial Neural Networking (ANN) to arrive at a design base. In the process of building the mathematical model, two key design parameters namely profile and performance were identified and model was constructed. Using this mathematical model, proto samples were prepared for a range of vacuum pump capacities and were tested. These test results were used for training the ANN to create the design base for any future design.

Vacuum pumps are predominantly used in diesel engines of passenger cars and trucks for generating vacuum in servo brake applications. With the emission norms getting stringent, there is a need for vacuum signal for EGR actuation, turbo-charger waste gate actuation and other servo applications. These multi-functional applications of vacuum pumps and the functional criticality in application like braking system demand an effective and reliable performance. In gasoline engines, the vacuum generated in the intake manifold is tapped for braking. The recent technology of gasoline direct injection compels the use of vacuum pump in gasoline engines also due to scarce vacuum in intake manifold. The performance of the vacuum pump is highly dependent on the opening and closing of the check valve sub-system, which is positioned between the vacuum reservoir and the pump at the suction side.

Vacuum pump is a device which gets the drive from engine cam shaft. In some designs, it is driven by the alternator shaft. The main function of vacuum pump is to evacuate the air from the brake booster tank, thus creating vacuum, which can be used for brake application. In addition to this, in new generation engines, to meet the Euro V emission targets, vacuum pump also has to create vacuum in the auxiliary tank which will be used to actuate the turbo charger waste gate actuation mechanism and EGR valve. The vacuum pump used for brake application when modified to perform the additional function of turbocharger may deteriorate the primary application performance. The tapping position and the size of the vacuum port for the auxiliary tank will influence the primary braking performance of the pump. The work described in this paper involves the systematic analysis of layout study of vacuum pump to meet the performance of the vehicle for brake and turbocharger applications.

The main challenge in designing the oil pump for gasoline & diesel engines is to optimize the pressure relief passage. Pressure relief passage is critical from design point of view as it maintains the oil pressure in the engine. Optimal levels of oil pressure and flow are very important for satisfactory performance and lubrication of various engine parts. Low oil pressure will lead to seizure of engine and high oil pressure leads to failure of oil filters, gasket sealing, etc. Optimization of pressure relief passage area will also reduce the power consumed by the pump. The Pressure relief system for this study consists of Pressure relief valve, spring, retainer, pressure relief passages. It is difficult to directly measure the flow through the pressure relief passage and is arrived based on the drop in flow at the delivery port. Numerical tool will be handy to predict the flow through the pressure relief passage and this can be used to optimize the flow through the bypass passage.

Emerging trend in the automotive industry all around the world is to develop vehicles to consume less fuel and to meet stringent emission norms by using engines of higher power to weight ratio and higher thermal efficiency. These advanced technology engines designed for high power output will use low viscous oil to reduce frictional losses and will operate at elevated temperature levels. Hence, the various auxiliaries and parts of these engines should be adaptable for the use of low viscous oil and should withstand higher temperatures. Oil pump is one such auxiliary which will be subjected to work with low viscous oil at higher temperatures levels. The oil pump taken for study and design improvement is an internal gear type positive displacement oil pump, used in a passenger car diesel engine. The un-meshing of the gears causes the inflow and meshing causes the outflow of lubricating oil. This process occurs continuously for providing a smooth pumping action.

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. Lubrication oil pump is one such source for parasitic loss of multijet diesel engine. One best way of reducing the same is by optimizing the power consumed by the oil pump without appreciably affecting the flow requirements of the engine. This paper describes an effective approach to bring down the power consumption of a fixed displacement oil pump by keying out various factors contributing for the same. Detailed here are the methods used for identifying those factors, modifications carried out in the design, and testing methods employed for the estimation, together with the results achieved. The test results show that it is possible to improve the power consumption of oil pump by 18% as a result of this study.

In today's scenario, improving the efficiency of the vehicle has become important and challenging. This is done by improving the efficiencies of individual parts that contribute to overall vehicle efficiency. In this paper, we have identified one such part, namely Vacuum Pump used in a multijet diesel engine and we have identified vacuum achievement time & power consumption as the performance parameters. A detailed analysis was done by way of building the cause and effect diagram to prioritize the effects. A detailed experimental study was conducted to identify the optimum level for each identified parameter, followed by checking the performance at that optimum condition. The test results show that it is possible to improve the performance of vacuum pump by 50% by combining the effects of all parameter from the existing level. Additionally this exercise also contributed to reduce the overall weight of the product by 25%.