Hai Trieu Phan^b, Nadia Caney^a,†, Philippe Marty^a, Stéphane Colasson^b, Jérôme Gavillet^b

Frontiers in Heat and Mass Transfer, Vol.2, No.1, pp. 1-6, 2011, DOI:10.5098/hmt.v2.1.3002

Abstract Experiments were performed to study the effects of surface wettability on flow boiling of water at atmospheric pressure. The test channel is a single rectangular channel 0.5 mm high, 5 mm wide and 180 mm long. The mass flux was set at 100 and 120 kg/m² s and the base heat flux was varied from 30 to 80 kW/m². Water enters the test channel under subcooled conditions. The sample surfaces are titanium (Ti) and diamond-like carbon (DLC) surfaces having a contact angle of 49° and 63°, respectively. The experimental results show different flow patterns that impact the heat transfer significantly.… More >

Sally M. Smith^*, Brenton S. Taft^† , Jacob Moulton

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-9, 2014, DOI:10.5098/hmt.5.6

Abstract This study investigates the wettability of fluid-solid interactions of interest for oscillating heat pipe (OHP) applications. Measurements were taken using two techniques: the sessile drop method and capillary rise at a vertical plate. Tested surface materials include copper, aluminum, and Teflon PFA. The working fluids tested were water, acetone, R-134a, and HFO-1234yf. A novel low-pressure experimental setup was developed for refrigerant testing. Results show that the refrigerants have significantly lower hysteresis than the water and acetone-based systems, which is thought to lead to better heat transfer in OHP design. More >

Demiao Chu¹, Redžo Hasanagić², Leila Fathi³, Mohsen Bahmani^3,*, Miha Humar⁴

Journal of Renewable Materials, Vol.11, No.12, pp. 4061-4078, 2023, DOI:10.32604/jrm.2023.043657

Abstract This study aimed to investigate the water absorption capacity of thermally modified and non-modified spruce and blue-stained spruce wood. The wettability of wood depends on various factors, including its type, density, porosity, and surface treatment. Wood can swell and become distorted when exposed to water or humidity, impacting its structural integrity. Hence, it is crucial to consider the water and water vapour uptake in the wood when choosing materials for applications that are likely to be exposed to moisture. Various moisture absorption tests were conducted to assess water absorption capacity, including short-term and long-term water absorption and water vapour absorption.… More > Graphic Abstract

Hongfei Ye^1,*, Chenguang Yin¹, Jian Wang¹, Yonggang Zheng¹, Hongwu Zhang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09741

Abstract The wetting behavior is ubiquitous in natural phenomenon as well as engineering application. As an intrinsic property of solid surface, the wettability with a controllable gradient has been an attractive issue with a wide application in various fields, including microfluidic devices, self-driven transport, biotechnologies, etc. Generally, it often requires elaborate design of microstructure or its response under the electrical, thermal, optical, pH stimuli, etc. However, the relevant complex underlying mechanism makes it difficult to construct quantitative relations between the wettability and the external field for the fine design. In this work, based on the bilayer two-dimensional materials, a simple controlling… More >

Yunyun Song¹, Xu Zhang¹, Jialei Yang¹, Zhongqiang Zhang^1,*, Guanggui Cheng¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09916

Abstract Although floating oil with large particle sizes can easily be separated from water by membrane separation methods, tiny oil droplets with tremendously small volume force and density gradient at oil-water interfaces within water lead to barriers of oil-water separation. Consequently, tiny oil droplets remain in the water, resulting in energy waste, environmental pollution and biological health hazard. Traditional super-wetting membranes with extremely small pore sizes were easily blocked during the oil-water separation process. Inspired by the cactus and rice leaf, we developed a superhydrophobic-superoleophilic surface with conical micro-arrays to realize ultrafast adsorption of tiny oil droplets within the water. The… More >

Shuang Cao^a,*, Hui Yang^a, Luxing Zhao^a, Tao Wang^a, Jian Xie^b,†

Frontiers in Heat and Mass Transfer, Vol.17, pp. 1-16, 2021, DOI:10.5098/hmt.17.17

Abstract Flow boiling heat transfer is an effective way to fulfill the energy transfer. The wettability of boiling surface influences the liquid spreading ability and the growth, departure, and release frequency of bubbles, which determines the heat transfer performance. According to the wettability and combination forms, boiling surface are classified into weak wetting surface, strong wetting surface, and heterogeneous wetting surface. Fabricating by physical, chemical method or coating the original surface with a layer of low surface energy, the weak wetting surface has more effective activation point and nucleation center density to improve heat transfer performance at low heat flux. The… More >

Qahtan A. Hamad¹, Hanaa A. Al-Kaisy¹, Mohanad N. Al-Shroofy¹, Noor K. Faheed^2,*

Journal of Renewable Materials, Vol.11, No.4, pp. 1601-1612, 2023, DOI:10.32604/jrm.2023.023213

Abstract This work aims to prepare chitosan (CS)-based coated layers, CS (10 wt% nanosilver/90 wt% CS, 10 wt% biotin/90 wt% CS, and 5 wt% nanosilver–5 wt% biotin)/90 wt% CS coatings are prepared, onto pure Ti substrate. The surface morphology of the novel CS composite coating was studied using field emission scanning electron microscopy, atomic force microscopy (AFM), Fourier transforms infrared (FTIR) and wettability test. Results show that the addition of (biotin, nanosilver) 5 Vol.% improves the properties of composite materials. Using different particles’ scale size aid in improving the combinations in the alginate, producing a dual effect on film properties. Coating… More > Graphic Abstract

Qingmin Pan¹, Yongzong Lu¹, Liang Xue², Yongguang Hu^1,*

Phyton-International Journal of Experimental Botany, Vol.92, No.2, pp. 411-421, 2023, DOI:10.32604/phyton.2022.023437

Abstract The wettability of leaf surface, commonly represented by contact angle (CA), affects various physiological and physical processes. The present study aims to better understand the wettability of tea leaves and elucidate its influence on the energy barrier of the droplet condensation process. The CA values of different leaf ages (young, mature and old) of five famous tea cultivars (Maolu, longjing 43, Huangjinya, Zhongcha 108 and Anji Baicha) were measured via the sessile drop method, and the micro-morphology of two cultivars leaves (Maolu, Zhongcha 108) was investigated by a 3D super depth-of-field digital microscope. Specifically, two radically distinctive types of CA… More >

Jianxin Cui^1,#, Zehui Ju^1,#, Lu Hong², Biqing Shu^1,3, Xiaoning Lu^1,*

Journal of Renewable Materials, Vol.10, No.11, pp. 2907-2919, 2022, DOI:10.32604/jrm.2022.019270

Abstract In order to improve hydrophobic characteristics which will affect the service performance of fast-growing poplar due to growing bacteria in the humid environment. In this study, a simple method was proposed to treat poplar via the high voltage electric field (HVEF) with copper as the electrode plate. Scanning electron microscope (SEM), Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (XRD) and contact angle tester were adopted to evaluate the surface morphology, surface group of poplar, crystallinity and wettability under HVEF. It was found by SEM that a large number of copper particles were uniformly attached to the surface of poplar. In… More >

Liliane Cruz Gomes de Souza Santos^1*, Eliane Ayres², Flávio Renato de Góes Padula¹

Journal of Renewable Materials, Vol.5, No.3-4, pp. 307-312, 2017, DOI:10.7569/JRM.2017.634121

Abstract In this study, bamboo powder and/or hollow glass microspheres were added to thermoplastic cassava starch in order to overcome its drawbacks. The composites were characterized by scanning electron microscopy (SEM), tensile testing, water contact angle measurement and X-ray diffractometry (XRD), in addition to their thermal properties. The mechanical strength of the composites showed a general decline with increasing bamboo powder content while the water contact angles increased up to 15% of bamboo powder content (% w/w dry starch). The addition of hollow glass microspheres provides an optimal balance between hydrophobicity and mechanical strength. The results pointed to improved properties that… More >