Liquid desiccant dehumidifiers (LDDs) has attracted much attention due to its advantages of energy-saving and environmental protection. However, dynamic characteristics of LDDs, which are essential to develop appropriate control methods, are still not clear at present. In this paper, the performance of a packed LDD was investigated under changes of desiccant inlet temperature and flow rate as well as air inlet humidity ratio, temperature and flow rate. Due to the random packings and interaction between air and desiccant, the air is normally distributed randomly during a dynamic process of LDDs and air outlet humidity ratio at the sampling point is serrated with time going. It was found that exponent function could be utilized to smooth the experimental result of air outlet humidity ratio, providing a simple way to determine the evaluation indexes like the response delay and response time as well as response rate, which could facilitate to evaluate dynamic characteristics of the dehumidifier. And through comparing those evaluation indexes corresponding to changes of different inlet parameters, it was revealed that air outlet humidity ratio was more sensitive to the change of desiccant or air flow rate, but not desiccant inlet temperature as indicated in a previous research getting from quasi-steady state experiments. Therefore, it would be more reasonable to select the desiccant or air flow rate as control variables instead of desiccant inlet temperature. Furthermore, preliminary control experiments were conducted to compare the performance of control algorithms developed based on the steady state characteristics and expert experience of dynamic characteristics. Results show that the control algorithm developed based on the expert experience of dynamic characteristics performs much better, which indicates that the obtained steady state characteristics in existing researches are unsuitable for developing control algorithms for a packed LDD. The dynamic characteristics revealed in current research paves the way for the future development of appropriate control algorithms.

液体干燥剂除湿机（LDD）因其节能环保的优势而备受关注。然而，对于开发适当的控制方法至关重要的 LDD 的动态特性目前仍不清楚。在本文中，研究了在干燥剂入口温度和流量以及空气入口湿度比、温度和流量变化下填充 LDD 的性能。由于空气与干燥剂的随机堆积和相互作用，空气在LDDs的动态过程中呈正态随机分布，采样点的空气出口湿度比随着时间的推移呈锯齿状。发现可以利用指数函数来平滑出风口湿度比的实验结果，提供了一种简单的方法来确定响应延迟、响应时间和响应率等评价指标，便于对除湿机的动态特性进行评价。并通过比较不同进气口参数变化对应的评价指标，发现出气口湿度比对干燥剂或空气流量的变化更敏感，而不是前人从准试验中得出的干燥剂入口温度的变化。稳态实验。因此，选择干燥剂或空气流量作为控制变量而不是干燥剂入口温度会更合理。此外，进行了初步控制实验，以比较基于稳态特性和动态特性专家经验开发的控制算法的性能。结果表明，基于动态特性专家经验开发的控制算法性能要好得多，这表明现有研究中获得的稳态特性不适合开发封装LDD的控制算法。当前研究中揭示的动态特性为适当控制算法的未来发展铺平了道路。这表明现有研究中获得的稳态特性不适合开发封装 LDD 的控制算法。当前研究中揭示的动态特性为适当控制算法的未来发展铺平了道路。这表明现有研究中获得的稳态特性不适合开发封装 LDD 的控制算法。当前研究中揭示的动态特性为适当控制算法的未来发展铺平了道路。