Experimental study of a LiCl-modified fibrous core material for energy wheels

Abstract

In this study, an experimental investigation is presented of a core material with irregular-shaped air flow channels for energy wheel applications. An experimental setup is established to test the performance of the material and study and analyze its characteristics. The core material has polyester wadding as the matrix and is sprayed with activated carbon as a hygroscopic material. Pores are found in the hygroscopic material attached to the fiber which contribute to the improvement of the heat exchange area between air and the material. To improve the performance of the material, it is modified by a lithium chloride solution. The test results showed that by implementing the lithium chloride modification, the hygroscopic capacity of the material can be significantly enhanced. The material latent and enthalpy efficiencies can be improved by about 10 % and 20 % at 0.5 rpm rotational speed with the action of lithium chloride at 2 % and 6 % mass concentration respectively. In addition, the efficiencies of the test material can be improved by more than 10 % by increasing its length from 38 mm to 50 mm. It is shown that the increase in the air flow rate leads to a decrease in the latent and enthalpy efficiencies. Mathematical models are used to analyze the latent efficiency of the material. Results showed that the efficiency of the modified material improved substantially at both high rotational speeds (>10 rpm) and low rotational speeds (0–10 rpm). Overall, the proposed core material offers an alternative low-cost and compact choice for energy wheel applications in air conditioning systems. The current study provides a preliminary assessment of such material and is aimed at establishing a better understanding of the promising potential in energy wheel applications.