Design of a magnetorheological fluid clutch

• Κύριος συγγραφέας: Κούρτης, Λάμπρος
• Άλλοι συγγραφείς: Kourtis, Lampros
• Γλώσσα: English
• Έκδοση: 2024
• Θέματα: Magnetorheological fluid clutch; Yield stress; Transferred torque; Bingham mode; Magnetorheological fluid; Μαγνητορεολογικος συμπλέκτης; Όριο ροής; Μεταφερόμενη ροπή; Μοντέλο Bingham; Μαγνητορεολογικά ρευστά

Clutches are the machine elements which connect the engine of a system with the rest of the system. During the engagement, the driving disc or discs transfer the power of the engine to the driven disc through the torque. A Magnetorheological Fluid Clutch utilizes magnetorheological fluid to achieve the engagement and the torque transfer. Magnetorheological fluids are liquids in which ferromagnetic particles are immersed. When the fluids are placed within a magnetic field the particles form chains in the direction of the field, drastically changing the properties of the fluid. The biggest change has to do with the yield stress. These fluids flow after a certain yield stress has been exceeded, thus increasing the shear stress they exert. The flow model for these smart fluids is Bingham's model. A MRF clutch creates an external magnetic field in order to stimulate the MRF. In this diploma thesis, a magnetorheological clutch in various geometric configurations and input currents has been investigated. Initially the magnetic problem was solved using ANSYS Magnetostatic software. Then after the magnetic field was known, it was used to find the yield stress. Finally fluid flow problem was solved using ANSYS Fluent. The shear stress of the MRF used to calculate the torque the clutch can transfer. Then the Torque Current curves are made for every configuration. Moreover Torque Radius curves were made in order to determine the best configuration. Finally it was calculated the power consumption for each configuration. In conclusion, the MRF clutches can controllably transfer large amount of torque.