## 5 Results and Discussion
### Off-Design Performance
It can be inferred that the subcooling of the compression subsystem decreases in this condition. In addition, the condenser temperature increases with the increasing chilled water temperature [27]. Therefore, the abovementioned effect increases the R410A temperature in the subcooler and the consequent improvement in the circulation water temperature of the subcooler. However, this increase of chilled water in the absorption subsystem is not notable, i.e., the inlet/outlet temperature of chilled water in the absorption subsystem enhances from 18.12 \({}^{\circ}\)C/16.14 \({}^{\circ}\)C to 19.44 \({}^{\circ}\)C/17.31 \({}^{\circ}\)C as the inlet temperature of the chilled water rises from 9 \({}^{\circ}\)C to 15 \({}^{\circ}\)C. Consequently, the heat load of the generator, cooling output and COP of the absorption subsystem just goes up by 6.33%, 7.72% and 1.31%, respectively, when the inlet temperature of the chilled water rises by 6 \({}^{\circ}\)C. Besides, the performance of the hybrid system benefits from the rise of the chilled water temperature. The heat load of the condenser in the compression subsystem, cooling capacity and COP of the hybrid system increases by 13.94%, 15.23% and 12.1%, respectively. For the compressor, the dependence of its consumption on the chilled water temperature is weak, owing to the decrease of the pressure ratio. The heat load and COP for different flow rates of hot water are shown in Figure 9. The decline of flow rate in the hot water decreases the generator temperature and the performance of the absorption subsystem. The heat load of the generator, cooling capacity and COP of the absorption subsystem comes down by 10.87%, 13.11% and 2.52%, respectively when the flow rate of hot water reduces by 80%. It can be inferred that the effect of the flow rate in the hot water on the performance of the compression subsystem is weak due to the slight variation of the subcooling power. The cooling capacity and COP of the hybrid system goes down by 1.55% and 1.89%, respectively. Especially, the change of condenser heat load in the compression subsystem and the work of the compressor can be ignored. Figure 8: Performance with the inlet temperature of chilled water. The heat load and COP for different flow rates of cooling water in the compression subsystem are displayed in Figure 10. As shown, the condenser temperature increases and the evaporator temperature maintains nearly constant with the decrease in the flow rate in the cooling water for the vapor compression chiller [27]. The improvement of the condenser temperature in the compression subsystem increases the temperature of the circulating water in the subcooler, resulting in the performance improvement of the absorption subsystem. However, the above-mentioned advantage is offset by the high condenser temperature of the compression subsystem, and leads to the poor performance of the hybrid system. The heat load of the generator, cooling capacity and COP of the absorption subsystem increases by 35.13%, 42.47% and 5.43%, respectively, as the flow rate of the cooling water in the compression subsystem goes down by 80%. However, simultaneously, the heat load of the condenser in the compression subsystem, cooling out and COP of the hybrid system comes down by 5.81%, 6.74% and 32.44%, respectively, and the compressor work rises by 38.04%. Figure 10: Performance with the flow rate of cooling water in the compression subsystem. Figure 9: Performance with the flow rate of hot water. The heat load and COP for different flow rates of chilled water are shown in Figure 5:0 As shown, the evaporator and condenser temperatures decrease with the decrease in flow rate in the chilled water for the vapor compression chiller [27]. Therefore, it can be inferred that the performances of the absorption and compression subsystems deteriorate when the flow rate of the chilled water decreases.