## 5 Conclusions  
In this paper, a particle flow modeling method based on energy analyses is proposed, aiming at solving the problems of modeling and analyzing the characteristics and mechanism of temperature variation of rock during deformation and fracturing. The numerical model has been built and calibrated, and a comparison study has been conducted between the laboratory and numerical experiment results. On this basis, further discussions have been held for a better understanding of the mechanism, considering different influencing factors. There are several conclusions that can be drawn, as follows:  
1. The proposed particle flow modeling method considers four different effects, including the thermoelastic effect, friction effect, damping effect, and heat conduction effect. The theoretical equations for calculating the temperature variation caused by each of the four effects have been provided, and this supplies a strong foundation for effective numerical modeling and further mechanism analyses. 2. The numerical model can well simulate the average value and distribution of the temperature variation of rock specimens under uniaxial compression, although there are several differences in the temperature distribution between the laboratory and numerical experiment results, owing to different heat exchange conditions between the physical and numerical environments. It is shown that this proposed method provides a better way for understanding the mechanism of temperature variation during the rock deformation and fracturing process, as this model can give more detailed information, including the evolution of stress and strain distribution, micro-crack initiation, propagation, coalescence, etc. during the process. This detailed information can provide a deeper insight into the characteristics and mechanisms compared with the field and laboratory observations and the continuous modeling method. 3. Based on this proposed modeling method, it is found that the temperature change has three different stages with different characteristics during the uniaxial compression. Figure 13: Effects of different particle size ratios on average temperature change (**a**), peak stress and the maximum value of average temperature change (**b**). In the different stages, the different effects play different roles in temperature change, and the thermoelastic effect has the greatest impact on temperature compared to the other three effects. In addition, the stress distribution and crack propagation have obvious influences on the local distribution of temperature. 4. Four parameters, including the thermal conductivity, friction coefficient, thermal expansion coefficient, and particle size ratio, have been considered and found to have different influences on the thermal and mechanical behaviors of the rock specimen under uniaxial compression. It is shown that the thermal expansion coefficient and the particle size ratio have more significant impacts on temperature variation than the other two factors. These findings increase our knowledge on the mechanism of temperature variation during rock deformation and fracturing processes. Above all, the proposed modeling method provides a new way to analyze the characteristics and mechanism of rock temperature variation during deformation and fracturing with more detailed information such as stress and strain distributions as well as micro-cracks. Although this study only considers intact rocks under uniaxial compression, in future research, more rock types with different structures under different stress conditions will be analyzed, and further mechanisms should be studied more consistently and comprehensively in combination with the laboratory experiments and the numerical studies based on the particle flow modeling method proposed in this paper. This proposed method can be applied for modeling laboratory experiments and field engineering, and it will be helpful for knowing more about the mechanism of rock failure in engineering and earthquakes.