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Currently, noise pollution has become one of the major environmental concerns. To address this, new noise standards and regulations are being introduced and mandate the tractor OEM’s (Original Equipment Manufacturer) to meet the defined noise levels. Fan noise from the cooling fan is one of the key contributors to the overall vehicle noise. Hence, the reduction of fan noise at the source is a very important and critical task. Even though fan noise is broadband in nature its aerodynamic noise sources are most dominant at the higher harmonics of the blade pass frequency (BPF). The aerodynamic noise of a fan can be varied by changing the fan geometry viz., blade profile, fan width and diameter, number of blades, and ring on its periphery. A cooling fan is an important component of the cooling system which ensures adequate airflow for radiator cooling and avoids engine overheating with uniform heat dissipation.

This paper deals with the application of Finite Element Analysis in accelerating the development of an automotive muffler. The essential function of a muffler is to route the exhaust gases from the engine exhaust manifold while reducing the noise and back-pressure. Noise reduction is an emerging concern in the automotive industry, and reduction in back-pressure enhances the fuel economy of the engine. Virtual simulation for back-pressure testing is performed by Computational Fluid Dynamic (CFD) analysis using AcuSolve CFD. Finite Element (FE) model generation of the muffler structure is performed using HyperMesh as the preprocessor. The structural mesh is modeled using 2D shell elements, wherein the internal tubes with fine perforated holes are considered. The CFD fluid meshing is done with tetra elements using AcuConsole as the CFD preprocessor.

This paper deals with the techniques of reducing noise in agricultural tractors. Noise reduction in agricultural tractors is an emerging concern and apart from meeting the noise norms it helps in increasing the productivity of farmers. Noise is also a factor affecting the health of the farmers. Two major European regulatory requirements are driver ear noise level and passer by noise level. Of the two regulatory requirement, driver ear noise is critical, since the limit is 86 dB (A) compared to 89 dB (A) of passer by noise limit which is measured at 7.5 meters from tractor. Various strategies for noise reduction are discussed in this paper including reduction at source level and passive solutions. Passive solutions are used where the timeline for development is short. Various passive solutions like acoustic foam design are discussed. Finally with the combination of active and passive solutions, driver ear noise target was met successfully.

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.