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Generally three cylinder engines due to less reciprocating masses are said to be more fuel efficient. Nevertheless, NVH problems caused by inherent imbalance forces and couples remain as draw back. NVH refinement levels can be improved by stiffening of the engine structure, material change, optimal design of the crank train, control of cylinder to cylinder pressure variation, etc. The objective of this study is to reduce the radiated noise of diesel engine by 2-3 dB (A) in the frequency range up to 4 kHz. Simulation and test based approach was demonstrated for reducing radiated engine noise. The NVH performance of the baseline engine has been evaluated using CAE simulation tools. Radiated noise from the critical components like oil sump, crank pulley and timing cover has been predicted and the critical modes having severe effect on radiated noise levels of the engine has been identified.

This paper analyses multiple hybrid electric concept for different agricultural applications for getting better vehicle efficiency through simulation modelling. Agricultural applications are entirely different from on road vehicles, so obtaining optimized vehicle efficiency is difficult because tractor is used for different applications and usage pattern on the same day. During design concept stage, the current diesel engine bare vehicle data will be used to set the required target of vehicle efficiency for hybrid electric vehicle. Design of Experiments (DOE) technique was used to predict the vehicle efficiency by modelling and analysis through AMESim Simulation tool for different hybrid electric types. The results were compared with the current vehicle performance. This simulation model integrates the vehicle, transmission, PTO, engine, hybrid electric model which consists of Motor/Generator, Battery and coupling mechanism, control model for both vehicle and hybrid.

Internal combustion engines involve various parasitic losses on vehicle level like that of Cooling Fans, Hydraulic pumps, Air compressors and Alternators. Because of which the available output power for applications is limited. The replacement of an existing mechanical Fan, which is driven by the engine crankshaft, by an electrically operated Fan reduces the engine frictional losses (Fan drag) resulting in a power gain. Fuel saved because of nil fan drag is available as a useful power for application. Mechanical fans operate on a fixed drive ratio with engine speeds and is directly proportional. Electrical fans can operate on constant speeds and is independent of engine speeds. There is a benefit of higher air-flow on max torque speeds which is not possible with a mechanical driven fan. There is no compromise in engine cooling performance, since the fan can now be placed suitably in the best airflow zone by computational fluid dynamics (CFD) analysis.

The vibration and acoustic behaviour of the internal combustion engine is a highly complex one, consisting of many components that are subject to loads that vary greatly in magnitude and which operate at a wide range of speeds. The interaction of these components and the excitation of resonant modes of vibration is a major problem for the powertrain engineer when optimising the noise and vibration characteristics of the engine. This paper summarises a study that has been undertaken to assess and optimise the dynamic behaviour of a current production diesel engine with the objective of reducing radiated noise from the engine. The dynamic behaviour of the diesel engine has been assessed using simulation tools. The dynamic analysis will predict the forces and displacements at each of the nodes of the model by forced response analysis. Predicted results and experimentally measured values were found to be in close agreement.

The automotive market has seen a steady increase in customer demands for quiet and more comfortable tractors. High noise at Operator Ear Level (OEL) of tractor is the major cause of fatigue to the operator. With growing competition, and upcoming legislative requirement there is ominous need for the agricultural tractor manufacturers to control noise levels. The objective of this study is noise reduction on agricultural tractor by stiffening sheet metal components. The design and analysis plays a major role for determining the root cause for the problem. Once the problem and its root cause were well defined, the solution for addressing the problem would be made clear. The engine excitation frequency and Sheet metal Components such as fender and platform natural frequency were coming closer and are leading to resonance.

Tractor operators prefer to drive more comfortable tractors in the recent years. The high noise and vibration levels, to which drivers of agricultural tractor are often exposed for long periods of time, have a significant part in the driver’s fatigue and may lead to substantial hearing impairment and health problems. Therefore, it is essential for an optimal cabin design to have time and cost effective analysis tools for the assessment of the noise and vibration characteristics of various design alternatives at both the early design stages and the prototype testing phase. Airborne excitation and Structure Borne excitation are two types of dynamic cabin excitations mainly cause the interior noise in a driver’s cabin. Structure-borne excitation is studied in this paper and it consists of dynamic forces, which are directly transmitted to the cabin through the cabin suspension. These transmitted forces introduce cabin vibrations, which in turn generate interior noise.

In any drive system, tooth mesh misalignment originates primarily from its torque transmitting components such as spline connections, gears, shafts, bearings and housing. The major influencing factors for tooth mesh misalignments are clearance between components, deflection, stiffness, thermal expansion, manufacturing limitations and assembly limitations. Tooth mesh misalignments in heavy duty off-highway applications like tractor, propagates drastically while handling severe loads and tends to shift the load distribution in a gear pair to an un-biased manner along the facewidth, resulting in high contact stresses and poor transmission performance. Misalignments definitely add few more decibels to the driveline system which will be an annoyance to the user. Moreover, mesh misalignments in any drive system cannot be eliminated and hence different approaches and methods were followed to compensate the misalignment.