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Powertrain Vibration Modelling using Virtual Prototypes
Prokop, Aleš ; Bauer, František (referee) ; Dundálek, Radim (referee) ; Novotný, Pavel (advisor)
This work deals with the matter of powertrain vibration reduction, focusing on the transmission. These units, depending on the purpose of utilization, consist of a high number of dimensionally complex components. These need to possess features, selected already in the design phase, which would guarantee smooth and quiet operation. A properly designed tooth profile and the related specified accuracy of manufacturing are one of the most important features. The basic function and the purpose of transmissions application indicate a relatively wide range of operating speeds and transmitted loads. Moreover, combination of both loading with improperly designed string’s parameter can cause a number of various problems. The vibration initiation with related noise from gear mesh belong to the most significant sources of issues. There are multiple mechanisms of oscillation initiation. Even when using the latest trends in the development of teeth, when their shape is upgraded and developed to meet specifically given load range, the above mentioned irregularity of transferred torque cannot be completely eliminated. Therefore, it is necessary, already in the design phase, to eliminate the transmission paths by which are vibrations transmitting to other components. People perceive this action in the form of vibration, noise, or temperature change in the surroundings. With the increasing comfort levels and number of produced vehicles the reduction of vibration and noise of machinery parts becomes stricter, including gears. The experimental approach is primarily used to assess the accuracy of designed gearboxes, but it is a very expensive and a time consuming method. Therefore, it is necessary to develop a process that utilizes both numerical simulation and experimental approach but also combines the advantages of both, particularly time and cost savings and comparability of results. For this purpose, the experimental gearbox is designed and manufactured including the single-stage gear enabling variable configurations in terms of the ratio change. The gearbox is subjected to numerical simulation of different complexity levels, as well as technical experiment. Furthermore, the universal virtual prototype in Multi-Body System ADAMS is created, which reflects the impact of several key parameters for proper functionality, such as axial distance, backlash, gear mesh stiffness, shaft mounting stiffness (bearings) and modal properties of the shafts and gearbox housing. Last but not least, the impact of imbalance or irregularity of input shaft speed is incorporated. The last part focuses on a brief description of the application of the presented methodology – modelling of vibrations on the tractor gearbox.
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Powertrain Vibration Modelling using Virtual Prototypes
Prokop, Aleš ; Bauer, František (referee) ; Dundálek, Radim (referee) ; Novotný, Pavel (advisor)
This work deals with the matter of powertrain vibration reduction, focusing on the transmission. These units, depending on the purpose of utilization, consist of a high number of dimensionally complex components. These need to possess features, selected already in the design phase, which would guarantee smooth and quiet operation. A properly designed tooth profile and the related specified accuracy of manufacturing are one of the most important features. The basic function and the purpose of transmissions application indicate a relatively wide range of operating speeds and transmitted loads. Moreover, combination of both loading with improperly designed string’s parameter can cause a number of various problems. The vibration initiation with related noise from gear mesh belong to the most significant sources of issues. There are multiple mechanisms of oscillation initiation. Even when using the latest trends in the development of teeth, when their shape is upgraded and developed to meet specifically given load range, the above mentioned irregularity of transferred torque cannot be completely eliminated. Therefore, it is necessary, already in the design phase, to eliminate the transmission paths by which are vibrations transmitting to other components. People perceive this action in the form of vibration, noise, or temperature change in the surroundings. With the increasing comfort levels and number of produced vehicles the reduction of vibration and noise of machinery parts becomes stricter, including gears. The experimental approach is primarily used to assess the accuracy of designed gearboxes, but it is a very expensive and a time consuming method. Therefore, it is necessary to develop a process that utilizes both numerical simulation and experimental approach but also combines the advantages of both, particularly time and cost savings and comparability of results. For this purpose, the experimental gearbox is designed and manufactured including the single-stage gear enabling variable configurations in terms of the ratio change. The gearbox is subjected to numerical simulation of different complexity levels, as well as technical experiment. Furthermore, the universal virtual prototype in Multi-Body System ADAMS is created, which reflects the impact of several key parameters for proper functionality, such as axial distance, backlash, gear mesh stiffness, shaft mounting stiffness (bearings) and modal properties of the shafts and gearbox housing. Last but not least, the impact of imbalance or irregularity of input shaft speed is incorporated. The last part focuses on a brief description of the application of the presented methodology – modelling of vibrations on the tractor gearbox.
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