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With the advent of stricter regulation for tail pipe emission and urge to reduce the carbon foot prints, the engine hardware has undergone through evolutionary changes over the years i.e., boosting, low viscosity engine oil, high pressure fuel injection, cooled EGR, friction reduction, downsizing etc. These technological changes have led to the challenge of increase in radiated noise level from the engine (source) due to increased number of auxiliary drives on engine i.e., Turbo charger, HP fuel pump along with faster combustion & harsher operating conditions. The fuel system is one such system which has become most intricate with operating pressure going above 2000bar in the fuel rail and capability of up to 10 fuel injection per combustion. These changes in hardware could result in abnormal noise generation during specific operating conditions which may result in customer annoyance inside vehicle cabin.

Over the years, Fuel efficiency and cabin comfort of vehicle has become increasingly important in buying decision and can significantly give competitive edge to the vehicle in marketplace. Weight and friction reduction of rotating and reciprocating components in engines is one of the proven approaches to improve the efficiency of internal combustion engine. To reduce the friction, the general approach is to use low viscosity engine oils, improve the surface finish and reduce the contact area of sliding elements, switch over from sliding contact to rolling contact etc. However sometimes this approach has adverse impact on engine NVH characteristics due to occurrence of abnormal transient noise due to mechanical knocking of the components in specific operating conditions.

Clutch actuation system in manual transmission is one of the key systems of power-train with which driver interacts frequently. Therefore its load and travel feeling are important to customer. Clutch actuation system consists of clutch pedal assembly, flexible cable mounted on body panel, and clutch release arm/ shaft assembly inside transmission unit assembly. Clutch pedal load, travel and engagement point are important parameters to specify the actuation feeling while designing the clutch actuation system. Validation of actual values is being done at proto vehicle testing stage, as final output calculation may not be accurate due to dependency on variables difficult to estimate. To overcome these difficulties a virtual dynamic model of the entire clutch actuation mechanism has been created in MBD software. Model input factors are based on actual testing results to improve the accuracy. The model predicts the clutch pedal load and travel values for a given set of vehicle inputs.

Manual transmission is one of the key system of power-train to which driver directly interacts, so its shift feeling is important for the merchantability. The importance of the gear shift quality of manual transmissions has increased significantly over the past few years as the refinement of other vehicle systems has increased and also due to rise in customer expectations. Shift Tower is a system to assist the driver during selecting and shifting of Gears. The dynamic interaction of shift Tower at a component level is difficult to interpret by traditional test methods and virtually impossible at concept stage. To overcome these difficulties a dynamic model of the entire Shift Tower mechanism i.e. Shift select lever, 3D Ramp, Detent Pin, Spring, Interlock mechanism has been created. The model predicts the gearshift quality i.e. Shift and Select force values for a given set of input parameters, which can be correlated against test data.