Experimental and numerical study of an evaporator with integrated latent heat storage for a compressed air dryer. (August 2021)

• Record Type: Journal Article
• Authors: Berto, Arianna; Azzolin, Marco; Del Col, Davide
• Is Part Of: Applied thermal engineering. Volume 195(2021)
• Publication Date: 2021-08
• Subjects: PCM -- Latent heat storage -- Partial load -- Dew point -- Air dryer -- Dynamic model; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2021.117170
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: A novel evaporator for an air dryer with integrated latent heat storage is designed. The performance of the system is experimentally analysed at partial loads. The system reduces the number of compressor cycles and dew temperature fluctuations. A 2D dynamic model of the evaporator has been developed in Matlab®. The model predicts with reasonable agreement the compressor ON and OFF durations. Abstract: In the current work, a latent heat storage system with organic phase change material is integrated in a plate-and-fin evaporator for air dehumidification, embedded in a refrigerated compressed air dryer. The effect of the phase change material type, evaporator geometry and dew point range on the fluctuations of the air temperature at the evaporator outlet and on the compressor cycle duration is experimentally investigated at partial loads. The addition of a paraffin phase change material allows to keep the air dew point temperature variations within the desired range at partial loads and to cut the energy consumption at the compressor up to 40% at 30% partial load. A two-dimensional model for simulating the dynamic behaviour of the plate-and-fin evaporator with latent heat storage is developed in Matlab®. The model aims at predicting the temporal variations of the dew point and phase change material temperatures inside the evaporator and the compressor ON/OFF cycle durations. The numerical results are compared with the experimental data, showing that the model is able to reproduce the performance of the evaporator at partial loads. A parametric study is carried out to analize the effect of the evaporator geometry and type of phase change material on the system performance.