J4 ›› 2016, Vol. 13 ›› Issue (3): 364-372.doi: 10.1016/S1672-6529(16)60309-8
Investigation of Fog Collection on Cactus-inspired Structures
Xianhua Tan1, Tielin Shi1, Zirong Tang1, Bo Sun1, Li Du1, Zhengchun Peng2, Guanglan Liao1
- 1. State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
2. College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518000, China
Investigation of Fog Collection on Cactus-inspired Structures
Xianhua Tan1, Tielin Shi1, Zirong Tang1, Bo Sun1, Li Du1, Zhengchun Peng2, Guanglan Liao1
- 1. State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
2. College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518000, China
摘要：
We demonstrate the application of cactus-inspired structures for fog collection. The drop-on-cone system is modeled to analyze Gibbs free-energy gradients, equilibrium positions and motion of drops. Normalized free energy and free energy gra-dient are presented to characterize barrel and clam-shell drops, revealing the relations of the driving force and wettability to the half-apex angle of the cones. Small half-apex angle results in long collecting length and weak driving force. Thus it is important for fog collection to balance the driving force and collecting length with a suitable half-apex angle. Fog collection experiments on cactus-inspired structures are conducted for verification. Inflection points around 1.1? are observed, where the fog collection ability is mainly limited by the weak driving force when below the inflection points, while increases with the collecting length when above the inflection points. These indicate that the half-apex angle at the inflection point is a compromise between the driving force and collecting length, agreeing with the normalized functions. The results also prove that the hydrophilic cones are more suitable for fog collection with regard to condensation and driving force. Our research offers design guidance for efficient fog collection structure.