Passive Atmospheric Water Harvesting Utilizing an Ancient Chinese Ink Slab

Abstract

Extraction of atmospheric water using a passive mechanism instead of a complex and advanced equipment has become an emerging subject. There is a clear record in MengxiBitan by Shen Kuo(1031~1095) that an ink slab has the ability to collect water from the air. Its mechanism is exactly similar to the Fangzhu [1], a recently investigated device for atmospheric water harvesting (AWH). Based on the Fangzhu device, a mathematical model for the AWH mechanism in ink slab-like materials is suggested. Using He’s frequency formulation and two-scale fractal derivatives the possible working mechanism of ink slab-like materials is investigated. The potential applications of ink slab-like structures for AWH in interior and exterior architecture are also presented and discussed. It is revealed that efficiency of the slabs highly depends on velocity and temperature of the flowing air and also its low-frequency characteristics.

Hybrid rayleigh–van der pol–duffing oscillator: Stability analysis and controller

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Numerical simulation of Chun-Hui He’s iteration method with applications in engineering

“…He’s frequency formulation (Geng and Cai, 2007; Zhang, 2009) and the Max-min approach (Ebaid, 2010; Shen and Mo, 2009; Ganji et al , 2010) to nonlinear oscillators were widely used in engineering, which are simpler and more effective than Differential Transform Method (Sheikholeslami and Ganji, 2016; Sheikholeslami et al , 2016; Mohsen et al , 2015; Sheikholeslami and Ganji, 2013), homotopy perturbation method (Vazquez-Leal and Boubaker, 2017; Adamu and Ogenyi, 2017), homotopy analysis method (Rajeev and Singh, 2017; Patel and Desai, 2017) and Adomian method (Sheikholeslami et al , 2013). Ancient Chinese also have applications in modern architecture, (He et al , 2021).…”

The homotopy perturbation method for fractional differential equations: part 2, two-scale transform

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