Investigation of Heat Exchanger Effectiveness Using a Nano-Coating Technology

2019 ◽  
Author(s):  
Allen Duffy
Keyword(s):  
Heat Exchanger ◽  
Coating Technology ◽  
Nano Coating

scholarly journals Performance Assessment of the Heat Exchanger with and without a Coating of Hybrid Nanoparticles the User Cooling System in Solar Heating Systems

2021 ◽  
Vol 39 (5) ◽  
pp. 1460-1468
Author(s):  
Khalid Faisal Sultan ◽  
Mohammed Hassan Jabal ◽  
Ameer Abed Jaddoa
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Cooling System ◽  
Hybrid Nanoparticles ◽  
Coating Process ◽  
Enhancement Of Heat Transfer ◽  
Lotus Effect ◽  
Nano Structure ◽  
Nano Coating ◽  
The Stability

The aim of this article was to examine the effect of hybrid nano – coating that could potentially impact the enhancement of heat transfer coefficient of distilled water, Reynolds number, and temperature through a swirl heat exchanger, as well as the indicator of the effect Zeta voltage in the coating process. In this experimental work, type of coating used was Aluminum (Al) + Aluminum oxide Al2O3. Outcomes of study showed that the coating of heat exchanger is much better than without coating in improving the thermal properties for liquids passing through heat exchanger as well as increasing the heat exchange through the surface of the exchanger. Results in the article indicated that the use of hybrid nano – structure coating is for inducing the feature of super – hydrophobicity for the surface that touches the fluid included within the heating transferring. Such feature can make an increase in the heating transferring factor and a decreasing in power losing produced via friction. This article indicated that the Zeta voltage analysis is to show the stability of the hybrid nanofluids used in the coating process. The enhanced technology depends upon the concept that exists in nature under the name “Lotus effect” to get super-hydrophobic surfaces. The rate of improvement in heat transfer using hybrid nanoparticles is 33% compared to that without coating condition.

A Study on the Deposition of Hydroxyapatite Nano Thin Films Fabricated by Radio-Frequency Magnetron Sputtering for Biomedical Applications

2020 ◽  
Vol 20 (7) ◽  
pp. 4114-4119 ◽  
Author(s):  
Woon-Jo Jeong
Keyword(s):  
Magnetron Sputtering ◽  
Biomedical Applications ◽  
Adhesion Force ◽  
Rf Magnetron Sputtering ◽  
Orthopedic Implants ◽  
Radio Frequency Magnetron Sputtering ◽  
Coating Technology ◽  
Pvd Coating ◽  
Nano Coating ◽  
Excellent Adhesion

We have developed a HA nano-coating technology suitable for dental and orthopedic implants using RF magnetron sputtering method which can achieve excellent adhesion to titanium compared with other various PVD coating technologies. As a result, the HA thin film prepared by RF magnetron sputtering has a thickness of about 1.6 [μm] and its adhesion force to base metal is about 11.93 [N] or more and Ca/P ratio is about 1.64, which is suitable for dental and orthopedic implants.

scholarly journals Improving the fatigue life of steel bars by using Nano-coating technology

2014 ◽  
Vol 3 (4) ◽  
pp. 523 ◽  
Author(s):  
Ali Yasir
Keyword(s):  
Fatigue Life ◽  
Thick Layer ◽  
Fatigue Tests ◽  
Coating Process ◽  
Coating Technology ◽  
Nano Coating ◽  
Steel Bars ◽  
Long Time ◽  
Coating Layers ◽  
Different Thickness

The fatigue failure is the reason of most mechanical failure for engineering materials. This work tried using the nano-coating technique to coat the steel bars and study the effect of this coating layers on fatigue life of steel. The Zinc Oxide (ZnO) used as it cheap and available in most labs of nanotechnology. The coating process done at different time of coating to get different thickness of coating layers. The result of fatigue tests for coated samples show increased in fatigue life for samples that coated for long time (thick layer of coat), and the increasing if fatigue life may reach to 4-times of its fatigue life for un-coated samples. Keywords: Fatigue, Fatigue Life, Steel Bars, Nano-Coating Technology, ZnO Coat.

scholarly journals Determining the Self-Limiting Electrospray Deposition Compositional Limits for Mechanically Tunable Polymer Composites

2021 ◽  
Author(s):  
Robert Green-Warren ◽  
Luc Bontoux ◽  
Noah McAllister ◽  
Dylan Kovacevich ◽  
Asaad Shaikh ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Glassy Polymers ◽  
The Self ◽  
Charge Accumulation ◽  
Electrospray Deposition ◽  
Coating Technology ◽  
Nano Coating ◽  
Base Matrix ◽  
Curing Agents ◽  
Scanning Electron

Electrospray deposition (ESD) is a versatile micro/nano coating technology that utilizes the competition between surface charge of a droplet and its surface tension to create monodisperse generations of micro/nano droplets. ESD can deposit uniform thin films by including dilute solutes in these droplets. One mode of ESD, self-limiting electrospray deposition (SLED), has been shown to exist when glassy polymers are sprayed in a volatile solvent below the polymer glass transition temperature (Tg). This leads to charge accumulation on the coating surface that slows the growth of the film thickness. Since solutes can be easily blended in dilute ESD solutions, we investigate the SLED limits of self-limiting and non-self-limiting solute blends. As a motivating application, we focus on mechanical properties of the film. Specifically, we blend self-limiting polystyrene (PS) and SU-8 epoxy resin with different non-self-limiting mechanical modifiers, such as plasticizers and curing agents. To characterize the resulting morphologies and mechanical properties, we employ scanning electron microscopy and nanoindentation of as received and smoothed films. The results illustrate the formation of composited polymers that exhibit self-limiting ability by SLED, depending on the interaction between the two components. Further, mechanical properties could be effectively fine-tuned within these compositional ranges. This signifies the 3D coating capabilities through SLED can be implemented incorporating additional functionalities and properties beyond the base matrix.

Direct Observation of Heat Exchanger Deposits by Cross Sectioning

1967 ◽  
Vol 25 ◽  
pp. 364-365
Author(s):  
R. W. Anderson ◽  
D. L. Senecal
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Heat Exchanger ◽  
Direct Observation ◽  
Cross Sections ◽  
Preparation Method ◽  
Specimen Preparation ◽  
Flowing Water ◽  
Transmission Electron ◽  
Deposit Layer

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

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