# Analysis on Flow and Temperature Field of High-Power Magnetorheological Fluid Transmission Device
## 7 Conclusions  
(a) The distribution characteristics of the cooling hydraulic force field are obtained: the minimum pressure and maximum pressure both appear at the connecting column, which are \(-1.4\) kpa and \(4.5\) kpa, respectively. In the same cooling gap, the pressure at both ends is significantly higher than the middle pressure, which can achieve rapid heat dissipation. The influencing factors of the distribution characteristics of the flow field are analyzed. The distribution of the velocity field of the coolant is similar at different speeds and different inlet velocities. The impact force is proportional, and the position of the inlet has no obvious influence on the flow field of the coolant. The increase in the diameter and number of magnetic columns is conducive to rapid heat dissipation;  
(b) The distribution characteristics of the temperature field under transient and ultimate slip power and the influencing factors of the temperature of MR fluid are obtained. At the same time, the limit of the slip power under rapid heat dissipation and phase change heat dissipation is obtained. The results show that the transmission power can still reach 200 kW, even under poor heat dissipation conditions;  
(c) Further research can be carried out to enhance steady-state slip power. For instance, a new heat dissipation system could be designed to inject the coolant directly into the cooling gap as it is the key to dissipating heat efficiently, it being paramount that the coolant flows rapidly into cooling gap, while the flowing coolant mainly relies on the discs rotating in the existing method. Furthermore, we can further prepare MR fluid with a higher temperature range.  
Conceptualization, X.W., Z.T. and F.X.; methodology, X.W. and Z.T. software, X.W.; validation, X.W. and Z.T.; formal analysis, X.W.; investigation, X.W., J.J. and Z.T.; resources, X.W. and Z.T.; data curation, X.W. and Z.T.; writing--original draft preparation, X.W., Z.T., Y.G. and H.L.; writing--review and editing, X.W., Y.G., H.L. and Z.T.; visualization, X.W., J.J. and H.L.; super-vision, X.W., Z.T. and F.X.; project administration, X.W., Z.T. and F.X.; funding acquisition, X.W. and Z.T. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (52005426, 51875560), Jiangsu Natural Science Foundation (BK20190155) and the Priority Academic Program Development of Jiangsu Higher Education Institutions.  
Not applicable.  
Figure 22: Influence of the inlet position on the temperature rise.  
**Acknowledgments:** The authors would like to gratefully acknowledge the National Natural Science Foundation of China (52005426, 51875560), Jiangsu Natural Science Foundation (BK20190155) and the Priority Academic Program Development of Jiangsu Higher Education Institutions. The authors would like to thank the editors and reviewers for their valuable comments and constructive suggestions.  
**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.