## 5 Conclusions  
The analytical and numerical results of this study contributed decisively to modeling the effects of horizontal transverse vibrations on the free convection heat transfer phenomenon and the ampacity of rectangular bus bars in an indoor environment, under normal and near-normal service conditions. This study considered ten rectangular bus bars with different cross-sections, assuming that they were heated by the corresponding ampacities and that they were vibrated horizontally with an amplitude of 0 to 5 mm at a frequency of 120 Hz, as well as with a frequency of 0 to 360 Hz at an amplitude of 3 mm. The existing experimental data were used to quantify the effects of vibration amplitude and vibration frequency on intensifying convection heat transfer from the bus bars, and increasing ampacity. The analytical and numerical results of this study were compared with each other, as well as with those from the relevant literature.  
The main conclusions of this study are as follows. First, the vibration amplitudes and frequencies considered can increase the bus bar ampacity up to 64.108% and 101.354%, respectively. These maximum increases correspond to the bus bar 0.0004 m \(\times\) 0.02 m. Second, it is found that the effect of vibration frequency on enhancing free convection heat transfer and, consequently, increasing the bus bar ampacity is significantly greater than the effect of vibration amplitude. Third, for the vibration classes A, B, and C, it is estimated that horizontal transverse vibrations can increase the bus bar ampacity up to 41.986% at a vibration frequency of 120 Hz. Fourth, the discrepancy between the results obtained using the proposed analytical model and the relevant experimental data is in most cases within the \(\pm\)10% limits. Fifth, the values of bus bar temperature obtained using the BUSBAR.m program and COMSOL 4.3 differ from the corresponding continuously permissible temperature by approximately \(\pm\)0.2 \({}^{\circ}\)C. Sixth, the accuracy of the proposed analytical model was successfully validated using the relevant experimental data and verified using the FEM.  
The results of this study can be useful for engineers and researchers involved in the design of bus bars in terms of including the effects of vibrations on the bus bar ampacity in normal operation. In addition, the next challenge could be to evaluate the effects of vibrations that occur in fault conditions on free convection heat transfer and associated short-circuit currents.  
Conceptualization, Li,G. and D.K.; methodology, D.K. and Lj,G.; software, D.K. and D.A.; validation, Lj,G., D.K. and D.A.; formal analysis, Lj,G., D.K., D.A. and S.J.; investigation, Lj,G. and D.K.; resources, D.K.; data curation, Lj,G., D.K., D.A. and S.J.; writing--original draft preparation, D.K.; writing--review and editing, Lj,G., D.K., D.A. and S.J.; visualization, S.J.; supervision, D.K. and D.A; funding acquisition, Lj,G., D.K., D.A. and S.J. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The data used in this research are available on request from the corresponding author.  
This manuscript was based on research conducted within program No. NIO 200155 supported by the Government of the Republic of Serbia.  
The authors declare no conflict of interest.