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Personal protection and perspiration evaporation are major features of a functional clothing system intended for outdoor environment applications. The aim of this article is to investigate the dynamic performance of an advanced multifunctional textile under solar radiation. The influence of the fabric properties of the double‐layer structure and the optical property of the photothermal nanocomposite based‐porous membrane (polyacrylonitrile PAN/carbon nanotube CNT) on the evaporation performance were experimentally and numerically discussed. Initially, a dedicated experimental study was conducted to measure the actual evaporation performance of the functional fabric. Following this, a two‐dimensional multi‐fluid model, simulated using COMSOL software, is applicable to predict experimental evaporation rates with a reasonable accuracy of 90%. The results showed that the dense structure had a greater wicking‐flow rate of 0.5 cm2 s−1 but lower evaporation performance in contrast to the permeable fabric. The incorporation of the photothermal nanofibers into the double‐layer fabric structure enhanced the surface‐localized heating capacity. Through the evaporation process, compared to conventional fabric, the advanced fabric structure exhibited approximately 3.5–4.4°C higher outer surface temperature. We concluded that the proposed multi‐layer structure has excellent potential to enhance the solar absorption efficiency in the visible range by 50% on average. Besides, the improved evaporation performance of the functional structure was 48% and 55%, respectively, under 0.6 and 1.0 sun illumination. In addition to the clothing field, this study can be extended for wide‐reaching applications based on solar vapor generation systems. [ABSTRACT FROM AUTHOR]

Carbon dioxide is considered as the main greenhouse gas responsible for climate change. Absorption of CO2 by liquid phase has gained attention as a means of mitigating environmental challenges. In this study, the effect of Fe3O4 nanoparticles on the CO2‐water mass transfer coefficient was experimentally evaluated in the presence and absence of a magnetic field. The absorption experiments were carried out in a falling liquid film absorber system in laminar and turbulent flow regimes. Fe3O4/water nanofluid was used in 0.001‐0.05 vol% concentrations. The results show that adding Fe3O4 nanoparticles to water increases the mass transfer coefficient (MTC), and that it increases with an increase in nanofluid concentration. For a concentration of 0.05 vol% nanofluid, the MTC was improved 111% and 13.7% in the turbulent and laminar flow regimes, respectively. The mass transfer coefficient of CO2 in water and effective mass transfer coefficient in nanofluid were increased up to 10% and 29% in the presence of a parallel alternative magnetic field, respectively. [ABSTRACT FROM AUTHOR]

Experimental and numerical studies were conducted on the mass transfer efficiency of new wire gauze structured packing. For serving this purpose, various operational conditions were studied to assess the optimal parameters such as HETP of PACK-2100 in the distillation column. The results indicate that the HETP values are enhanced in comparison to conventional ones. In addition, the HETP slowly increases from 4 to 6 cm as mass flow rates of air and liquid flow are increased. The numerical simulations were also performed to describe the performance of the PACK-2100. The Eulerian-Eulerian multiphase approach is applied to calculate the value of HETP and pressure drop. The computational results confirmed that our experimental results. The average relative error between CFD predictions and the experimental data for the prediction of mass transfer efficiency is 20.45%. [ABSTRACT FROM AUTHOR]

Extensive usage of the structured packings in various industrial applications has led to comprehensive investigations of their properties and performance. Among various methods of modeling, computational fluid dynamics (CFD) is an efficient approach to present full details of fluid behavior inside structured packings. This review focuses on the application of CFD for investigation and development of the structured packings. Applications of the CFD for the simulation of gas–liquid flow behavior, flow distribution, liquid hold-up, and mass transfer are extensively reviewed. Literature survey of the available CFD studies can provide a comprehensive and descriptive insight about governing mechanisms of fluid flow inside packings and reveals qualitative/quantitative effects of the process variables on the packed system. [ABSTRACT FROM AUTHOR]