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The paper aims at numerically modeling the flow and thermal processes occurring in an agricultural tractor using Computational Fluid Dynamics (CFD) and determines the comfort level of the tractor operator during working condition. The motive of the investigation is to develop and demonstrate capabilities of CFD as an automotive analysis tool. The work describes a methodology that significantly stream lines the process of thermal flow taking place in a tractor by utilizing state-of-the art computer simulation of air flow and heat transfer. The numerical investigation carried out with a three-dimensional geometry of the vehicle assembly and the measurements were taken from the vehicle. The geometry created with Pro/Engineer formed the domain for the automatically generating discretized grid contained the majority of the main components within the underhood environment.

Steering wheel vibration is one of the major factors in determining the operator comfort in agricultural tractors. Main sources of steering wheel vibration are engine imbalance, resonance of steering system, lesser damping, road / field induced vibration, etc. The European Council directive 2002/44/EC recommendations are taken as guidelines in this work. Steering vibration study was conducted on various tractor models (40 - 50 kW range) and one tractor was identified for improvement. Upon detailed analysis on that particular tractor, it was found that the resonance of steering system with engine excitation is the root cause for excessive vibration. Various methods to reduce vibration due to resonance were considered, such as shifting the natural frequency away from the second order engine frequency and increasing damping coefficient to reduce the vibration amplitude at resonance. Six different concepts were generated and analyzed using the design assessment matrix.

The scope of tractor usages are widely expanding to various non-agricultural and construction/earthmoving applications like loaders, dozers etc. The tractors with manual transmission driveline subjected to such heavy duty cycles are having conventional dry type clutches in general. These types of dry clutch when operated in such heavy application generate large amount of heat within shorter period of time on the surfaces of friction discs. This increase in disc surface temperature determines not only the level of the friction but also the rate of wear and durability. Number of clutch operation per minute for this application is also increasing to meet the improved productivity requirements. Analysis shows that the rate of heat removal from the friction disc through oil flow system is higher compared to oil immersion type. In this work, an oil spatter concept is designed to provide active circulation of oil to the multi disc clutch during engaged conditions.

Tractors along with implements are used to prepare the soil. There are two broad classification in implements attached, one is passive or trailed implements and other one is active tilling implements which will take drive from engine through Power Take Off (PTO). The drivelines for transmission and PTO should have clutches to engage / disengage them from the engine while changing gears and switching PTO On/Off respectively. In present scenario, there are independent clutches for both drivelines to operate PTO driven implements without disrupting vehicle speed. In general, IPTO is being achieved by dry clutch which is integral with engine mounted clutch operated by separate linkages or by hydraulically operated wet clutch located in PTO driveline after auxiliary pump. An attempt is made with mechanically operated wet clutch in the PTO driveline to have an IPTO.