In this paper, several thermodynamic optimization strategies are implemented to tap the potential of multiple water injections in thermodynamic balancing of combined heat and mass transfer process in air humidifier. The all-state of humid air including unsaturation, saturation and supersaturation states are particularly considered. Based on finite difference method, theoretical models are integrated with multiple injection methods. In the off-design analysis, the equipartition process of the driving forces including heat transfer temperature difference and mass transfer pressure difference are full of attention and interest. The research results present that entropy generation minimization is achieved when the values of heat capacity rate ratio equal to unity for all the cases. A larger value of the number of injections will improve the equipartition process of the driving forces, resulting in a reduction of total normalized entropy generation. In addition, it is found that these driving forces can be better balanced with larger number of injections and smaller injection ratio, when the heat capacity rate ratio is constant. Moreover, it is observed that energy effectiveness can be improved and the total normalized entropy generation is diminished as the inlet relative humidity augments, with a minimum normalized entropy generation of 0.0045 emerged at φ_i = 0.85. Furthermore, it is also highlighted that controlling and adjusting the relative humidity of inlet humid air for the optimization of thermal devices and engineering systems is significant and available, especially referred to the all-state of humid air.

在本文中，实施了几种热力学优化策略，以挖掘多次注水在空气加湿器传热传质过程的热力学平衡中的潜力。特别考虑潮湿空气的所有状态，包括不饱和状态、饱和状态和过饱和状态。基于有限差分法，将理论模型与多种注入方法相结合。在非设计分析中，传热温差、传质压差等驱动力的均分过程备受关注。研究结果表明，在所有情况下，当热容率比值均等于1时，可以实现熵产生最小化。较大的注射次数值将改善驱动力的均分过程，从而减少总归一化熵的产生。此外，发现当热容率比恒定时，这些驱动力可以通过较大的喷射次数和较小的喷射比得到更好的平衡。此外，据观察，随着入口相对湿度的增加，能量效率可以提高，总归一化熵生成减少，最小归一化熵生成为 0.0045 当热容率比恒定时。此外，据观察，随着入口相对湿度的增加，能量效率可以提高，总归一化熵生成减少，最小归一化熵生成为 0.0045 当热容率比恒定时。此外，据观察，随着入口相对湿度的增加，能量效率可以提高，总归一化熵生成减少，最小归一化熵生成为 0.0045φ _i  = 0.85。此外，还强调了控制和调节入口湿空气的相对湿度对于热力装置和工程系统的优化具有重要意义和可利用性，尤其是针对湿空气的全状态。