scholarly journals A Study on the Flow Characteristics of Copper Heavy Metal Microfluidics with Hydrophobic Coating and pH Change

2021 ◽  
Vol 11 (10) ◽  
pp. 4328
Author(s):  
Jung-Geun Han ◽  
Dongho Jung ◽  
Jong-Young Lee ◽  
Dongchan Kim ◽  
Gigwon Hong
Keyword(s):  
Heavy Metal ◽  
Capillary Tube ◽  
Flow Characteristics ◽  
Hydrophobic Surface ◽  
Ph Change ◽  
Bottom Part ◽  
Hydrophobic Coating ◽  
Surface Contact Angle ◽  
Basic Technology ◽  
Coated Surfaces

The present study purpose was to identify the flow characteristics of the drainage filter considering the characteristics of the landfill site, and to study the basic technology for efficient remediation of heavy metals. To this end, copper heavy metal was selected in consideration of landfill characteristics, and a study on flow characteristics was conducted using hydrophobic coated capillary tubes and microparticles. It was confirmed that the flow rate decreased as the pH increased at the hydrophobic surface, and pH 4, 6, and 8 flowed similarly in the center of the capillary tube, but decreased at pH 10. In the bottom part, it moved at the slowest speed of 1~4 μm/s and middle of center moved 17~25 μm/s. There was little change in flow in the CFD (Computational Fluid Dynamics) numerical analysis considering the surface contact angle, which is a hydrophobic characteristic, and the velocity coefficient was presented by regression analysis through the experimental results. In this way, the current study will be a basic examination of the selective remediation process of pH on hydrophobic coated surfaces.

scholarly journals CFD Analysis of the Optimization of Length of Capillary Tube for a Vapor Compression Refrigeration System

2021 ◽  
Vol 9 (8) ◽  
pp. 2567-2578
Author(s):  
Ms. K. P. Bhangle
Keyword(s):  
Capillary Tube ◽  
Flow Analysis ◽  
Small Diameter ◽  
Flow Characteristics ◽  
Working Fluid ◽  
Vapor Compression ◽  
Adiabatic Flow ◽  
Ansys Cfx ◽  
Vapor Compression Refrigeration ◽  
R 134A

Abstract: The capillary tube is commonly employed in refrigerant flow control systems. As a result, the capillary tube's performance is optimal for good refrigerant flow. Many scholars concluded performance utilising experimental, theoretical, and analysis-based methods. This paper examines the flow analysis of a refrigerant within a capillary tube under adiabatic flow circumstances. For a given mass flow rate, the suggested model can predict flow characteristics in adiabatic capillary tubes. In the current work, R-134a refrigerant has been replaced by R600a refrigerant as a working fluid inside the capillary tube, and the capillary tube design has been modified by altering length and diameter, which were obtained from reputable literature. The analysis is carried out using the ANSYS CFX 16.2 software. The results show thatutilising a small diameter and a long length (R600a refrigerant flow) is superior to the present helical capillary tube. The most appropriate helical coiled design with a diameter of 0.8 mm and a length of 3 m is proposed. Keywords: Capillary Tube, Condenser, Refrigeration effect, CFD.

scholarly journals A121 A study on Flashing Flow Characteristics of CO_2 in a Capillary Tube

2012 ◽  
Vol 2012 (0) ◽  
pp. 9-10
Author(s):  
Kenta Kobayashi ◽  
Hitoshi Asano ◽  
Saleh Abo-Efadl ◽  
Koji Takiguchi ◽  
Toshiaki Tuchiya ◽  
...  
Keyword(s):  
Capillary Tube ◽  
Flow Characteristics

scholarly journals One-Step Preparation of Durable Super-Hydrophobic MSR/SiO2 Coatings by Suspension Air Spraying

Micromachines ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 677 ◽  
Author(s):  
Zhengyong Huang ◽  
Wenjie Xu ◽  
Yu Wang ◽  
Haohuan Wang ◽  
Ruiqi Zhang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Adhesion Strength ◽  
Contact Angle Hysteresis ◽  
Surface Hardness ◽  
Hierarchical Structures ◽  
Hydrophobic Surface ◽  
Water Contact ◽  
Hydrophobic Coating ◽  
Mechanical Durability ◽  
One Step

In this study, we develop a facial one-step approach to prepare durable super-hydrophobic coatings on glass surfaces. The hydrophobic characteristics, corrosive liquid resistance, and mechanical durability of the super-hydrophobic surface are presented. The as-prepared super-hydrophobic surface exhibits a water contact angle (WCA) of 157.2° and contact angle hysteresis of 2.3°. Mico/nano hierarchical structures and elements of silicon and fluorine is observed on super-hydrophobic surfaces. The adhesion strength and hardness of the surface are determined to be 1st level and 4H, respectively. The coating is, thus, capable of maintaining super-hydrophobic state after sand grinding with a load of 200 g and wear distances of 700 mm. The rough surface retained after severe mechanical abrasion observed by atomic force microscope (AFM) microscopically proves the durable origin of the super-hydrophobic coating. Results demonstrate the feasibility of production of the durable super-hydrophobic coating via enhancing its adhesion strength and surface hardness.

DEVELOPMENT OF CARBON-BASED COATING OF EXTREMELY HIGH TOUGHNESS WITH GOOD HARDNESS

2004 ◽  
Vol 03 (04n05) ◽  
pp. 571-578 ◽  
Author(s):  
S. ZHANG ◽  
X. L. BUI ◽  
Y. FU ◽  
H. DU
Keyword(s):  
Residual Stress ◽  
Contact Angle ◽  
Amorphous Carbon ◽  
High Hardness ◽  
Hydrophobic Surface ◽  
Nanocomposite Coating ◽  
High Toughness ◽  
Surface Contact ◽  
Surface Contact Angle ◽  
Carbon Based

Metallic Al was doped into amorphous carbon (a-C) to form a matrix of a-C(Al) of very low residual stress and high toughness at the expense of some hardness. Nanocrystallites of TiC (nc-TiC) of a few nanometers in size were embedded in this matrix to bring back the hardness. The nanocomposite coating of nc-TiC/a-C(Al) was deposited via co-sputtering of graphite, Ti , and Al targets. Although the nanocomposite coating exhibited a moderately high hardness (about 20 GPa), it possessed extremely high toughness (about 55% of plasticity during indentation deformation) and low residual stress (less than 0.4 GPa), smooth (Ra=5.5 nm ), and hydrophobic surface (contact angle with water reaches 100°).

An Experimental Study of the Flow of R-407C in an Adiabatic Spiral Capillary Tube

2009 ◽  
Vol 1 (4) ◽  
Author(s):  
M. K. Mittal ◽  
R. Kumar ◽  
A. Gupta
Keyword(s):  
Experimental Data ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Capillary Tube ◽  
Flow Characteristics ◽  
Flow Rates ◽  
Tube Test ◽  
Mass Flow Rates ◽  
R 134A

The objective of this study is to investigate the effect of coiling on the flow characteristics of R-407C in an adiabatic spiral capillary tube. The characteristic coiling parameter for a spiral capillary tube is the coil pitch; hence, the effect of the coil pitch on the mass flow rate of R-407C was studied on several capillary tube test sections. It was observed that the coiling of the capillary tube significantly reduced the mass flow rate of R-407C in the adiabatic spiral capillary tube. In order to quantify the effect of coiling, the experiments were also conducted for straight a capillary tube, and it was observed that the coiling of the capillary tube reduced the mass flow rate in the spiral tube in the range of 9–18% as compared with that in the straight capillary tube. A generalized nondimensional correlation for the prediction of the mass flow rates of various refrigerants was developed for the straight capillary tube on the basis of the experimental data of R-407C of the present study, and the data of R-134a, R-22, and R-410A measured by other researchers. Additionally, a refrigerant-specific correlation for the spiral capillary was also proposed on the basis of the experimental data of R-407C of the present study.

An investigation into the anti-icing properties of fabrics used for the outer layer of firefighter clothing

2018 ◽  
Vol 89 (8) ◽  
pp. 1500-1511 ◽  
Author(s):  
Lun Han ◽  
Xiaoming Zhao ◽  
Jannette Eveline Kidalla
Keyword(s):  
Outer Layer ◽  
Photoelectron Spectroscopy ◽  
Smooth Surface ◽  
Hydrophobic Surface ◽  
Hydrophobic Property ◽  
Water Contact ◽  
Hydrophobic Coating ◽  
Before And After ◽  
Coating Method ◽  
Fabric Surface

The anti-icing properties of fabrics can be considered as involving two parts, the super-hydrophobic property and the ease of ice removal property. In this study, a super-hydrophobic surface was built on to the outer layer of firefighter clothing using nano-silica, C13H13F17O3Si, C19H42O3Si and PU-2540 using a coating method. This coating stops water drops from staying on the fabric surface easily. At the same time, an ultra-smooth surface was built on to the super-hydrophobic surface already created on the fabric using perfluoropolyethers (PFPE) oil by a dipping method, which adds an ice removal function to the fabrics. The anti-icing properties of the samples prepared in the research described in this paper have been investigated using field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), ease of ice removal property tests and static water contact angle analysis. At the same time, the thermal protective performance (TPP) of the samples, before and after super-hydrophobic treatment, was studied by a TPP tester. Results show that the super-hydrophobic coating with an ultra-smooth surface can significantly increase the anti-icing properties of the fabrics used for the outer layer of firefighter clothing. C13H13F17O3Si and C19H42O3Si can improve the hydrophobic properties of the coating. The anti-icing coating in this paper can increase the TPP of the fabrics.

Visualization of Dispersed Phase Flow in Centrifugal Extractor Using Taylor-Couette Vortex Flow

2011 ◽  
Author(s):  
Hideharu Takahashi ◽  
Hiroshige Kikura ◽  
Kenji Takeshita ◽  
Masanori Aritomi
Keyword(s):  
Flow Field ◽  
Vortex Flow ◽  
Flow Characteristics ◽  
Metal Extraction ◽  
Dispersed Phase ◽  
Cylinder Surface ◽  
Centrifugal Extractor ◽  
Hydrophobic Coating ◽  
Measurement And Analysis ◽  
Taylor Couette

For studying the designs and running operations of an extractor which uses Taylor-Couette vortex flow, we focused on a metal extraction system as one of the extraction models of heat generating nuclides and observed the flow patterns of dispersed phase by dyeing the phase in the extractor, and we investigated the effects of hydrophobic coating applied to the inner cylinder surface on the flow characteristics. Moreover, for the quantitative measurement and analysis of the flow field, we evaluated the applicability of Ultrasonic Velocity Profiler (UVP) to flow field measurement. Thorough these visualization methods of dispersed phase in a centrifugal extractor using Taylor-Couette vortex flow, we examined the relation between flow field and extraction characteristics of the extractor.

Research of bubble flow characteristics in microfluidic chip

2017 ◽  
Vol 31 (10) ◽  
pp. 1750109
Author(s):  
Chao Qiu ◽  
Han Cheng ◽  
Shuxian Chen
Keyword(s):  
Heat Flux ◽  
Microfluidic Chip ◽  
High Speed ◽  
Flow Characteristics ◽  
Hydrophobic Surface ◽  
High Speed Photography ◽  
Bubble Flow ◽  
Hydrophilic Surface ◽  
Biological Detection ◽  
Speed Up

Bubble is the heart of the microfluidic chip, which takes a significant role in drug release, biological detection and so on. In this case, bubble flow characteristics in microfluidic chip are the key to realize its function. In this paper, bubble flow characteristics in the microfluidic chip have been studied with high speed photography system by controlling the wettability and the heat flux of the microelectrode surface. The result shows that bubble flows faster on the electrode with hydrophobic surface. In addition, loading current to the electrode with hydrophilic surface could also speed up the movement of bubble, and the flow rate of bubble increases with the increasing heat flux of the electrode.

Sign in / Sign up

Export Citation Format

Share Document