## 3 Results and Discussion
### Comparative Analysis of Internal Flow Characteristics Inside Steam Ejectors
In addition, the average temperature of the shock wave train g in the mixing chamber for the wet steam model was also higher than that for the ideal gas model. This was due to the nonequilibrium condensation phenomenon in the expansion process of the primary flow and the release of latent heat of condensation. In order to further analyze the difference in the temperature distribution between the two models, the temperature distribution along the steam ejector axis under different \(P_{m}\) is shown in Figure 9. It can be seen that when the \(P_{m}\) was 50,000 Pa, the temperature at the nozzle exit for the wet steam model was 315 K, and that for the ideal gas model was 183 K. The temperature at the nozzle exit for the wet steam model was 72.1% higher than  
Figure 6: Pressure contours under different \(P_{m}\) for wet steam model and ideal gas model. that for the ideal gas model. With the increase in \(P_{m}\), the temperature at the nozzle exit increased from 315 K to 324 K for the wet steam model and the temperature at the nozzle exit increased from 183 K to 188 K for the ideal gas model. According to the analysis of the nonequilibrium phase change characteristics, it could be seen that the Wilson point moved towards the nozzle throat and the condensation position was closer to the nozzle throat with the increase in the \(P_{m}\). This increased the amount of condensation in the liquid phase of the nozzle divergence section and the release of latent heat. Therefore, the change in the temperature at the nozzle exit for the wet steam model was larger than that for the ideal gas model. The choking effect occurred near the inlet of the constant section. When the \(P_{m}\) was 50,000 Pa, the choking temperature for the wet steam model was 325 K, and that for the ideal gas model was 336 K. In the process of mixing the primary flow and the secondary flow, the mixed flow was in the superheated state. At this time, the liquid-phase evaporation absorbed the heat of the surrounding mixed flow and reduced its temperature. Therefore, the choking temperature for the wet steam model was lower than that for the ideal gas model. With the increase in the \(P_{m}\), the choking temperature for the wet steam model increased from 325 K to 329 K and the choking temperature for the ideal gas model increased from 336 K to 342 K. After the mixed flow entered the diffuser, the temperature decreased due to expansion. Then, the temperature rose suddenly because of the shock wave. With the increase in the \(P_{m}\), the temperature before the shock wave in the diffuser decreased from 284 K to 282 K for the wet steam model and decreased from 250 K to 224 K for the ideal gas model. The mixed flow was supercooled during the expansion. When the subcooled degree reached a certain threshold, the droplets began to condense. The latent heat released during the condensation process caused the \(T_{m}\) to rise and was close to the saturated state. The increase in the \(P_{m}\) caused the expansion of the primary flow to increase and the \(T_{m}\) to decrease rapidly. However, at the same time, the amount of condensation in the liquid phase also increased. This allowed more latent heat of condensation to be released into the primary flow and, thus, offset the decrease in the \(T_{m}\) caused due to the expansion. Therefore, the variation in the \(T_{m}\) before the shock wave for the wet steam model was smaller than that for the ideal gas model. The variation in the Mach number could reflect the shock wave intensity well. The Mach number contour for the wet steam model and the ideal gas model under different \(P_{m}\) is shown in Figure 10. It was found that the Mach number at the nozzle exit for the wet steam model was lower than that for the ideal gas model. Combined with the analysis of the pressure distribution, it could be seen that the release of condensation latent heat in the nozzle produced condensation shock waves in the nozzle divergence section. The choking effect of the condensation shock wave resulted in a decrease in the Mach number.