Studies of the Flame Spraying of Polymers

1996 ◽  
Author(s):  
D.J. Varacalle ◽  
K.W. Couch ◽  
V.S. Budinger
Keyword(s):  
Bond Strength ◽  
Combustion Process ◽  
Experimental Studies ◽  
Polymer Coatings ◽  
Flame Spraying ◽  
Knoop Microhardness ◽  
Resultant Coating ◽  
Strength Characterization ◽  
Thermally Sprayed

Abstract Experimental studies of the subsonic combustion process have been conducted in order to determine the quality and economics of polyester, epoxy, urethane, and hybrid polyester-epoxy coatings. Thermally sprayed polymer coatings are of interest to several industries for anti-corrosion applications, including the infrastructural, chemical, automotive, and aircraft industries. Classical experiments were conducted, from which a substantial range of thermal processing conditions and their effect on the resultant coating were obtained. The coatings were characterized and evaluated by a number of techniques, including Knoop microhardness tests, optical metallography, image analysis, and bond strength. Characterization of the coatings yielded thickness, bond strength, hardness, and porosity.

scholarly journals Effects of Nanosecond Repetitively Pulsed Discharges Timing for Aeroengines Ignition at Low Temperature Conditions by Needle-Ring Plasma Actuator

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5814
Author(s):  
Ghazanfar Mehdi ◽  
Sara Bonuso ◽  
Maria Grazia De Giorgi
Keyword(s):  
Combustion Process ◽  
Experimental Studies ◽  
Plasma Actuator ◽  
Inlet Temperature ◽  
Time Interval ◽  
Short Time Interval ◽  
Air Plasma ◽  
Plasma Discharges ◽  
Plasma Actuation

These days, various national and international research organizations are working on the development of low NOx combustors. The present work describes the experimental and numerical characterization of flow dynamics and combustion characteristics in a rectangular burner. A ring-needle type plasma actuator was developed and driven by a high voltage nanosecond pulsed generator under atmospheric conditions. Smoke flow visualizations and Proper Orthogonal Decomposition (POD) were carried out to identify the relevant flow structures. Electrical characterization of the non-reactive flow was carried out to predict the electrical power and the optimum value of the reduced electric field (EN), which is useful for the implementation of a numerical model for the study of plasma-assisted ignition. A detailed plasma kinetic mechanism integrated with all excited species was considered and validated with experimental studies. Numerical modeling of plasma ignition has been performed by coupling ZDPlasKin with CHEMKIN. Energy and power consumption for methane/air plasma actuation is higher than the air plasma actuation. This could be due to the excitation and ionization of methane that required more energy deposition and power. The mole fraction of O atoms and ozone was higher in the air than the methane/air actuation. However, O atoms were produced in a very short time interval of 10−7 to 10−6 s; in contrast, the concentration of ozone was gradually increased with the time interval and the peak was observed around 10−1 s. Plasma discharges on the methane/air mixture also produced radicals that played a key role to enhance the combustion process. It was noticed that the concentration of H species was high among all radicals with a concentration of nearly 10−1. The concentration peak of CH3 and OH was almost the same in the order of 10−2. Finally, the mixture ignition characteristics under different low inlet temperatures were analyzed for both air and methane/air plasma actuation in the presence of different plasma discharges pulses numbers. Results showed that it is possible to reach flame ignition at inlet temperature lower than the minimum required in the absence of plasma actuation, which means ignition is possible in cold flow, which could be essential to address the re-ignition problems of aeroengines at high altitudes. At Ti = 700 K, the ignition was reached only with plasma discharges; ignition time was in the order of 0.01 s for plasma discharges on methane/air, lower than in case of plasma in air, which permitted ignition at 0.018 s. Besides this, in the methane/air case, 12 pulses were required to achieve successful ignition; however, in air, 19 pulses were needed to ignite.

Flame Spraying of Polymers

1997 ◽  
Author(s):  
D.J. Varacalle ◽  
D.P. Zeek ◽  
K.W. Couch ◽  
D.M. Benson ◽  
S.M. Kirk
Keyword(s):  
Thermal Spraying ◽  
Statistical Design ◽  
Compositional Analysis ◽  
Deposition Efficiency ◽  
Polymer Coatings ◽  
Fractional Factorial ◽  
Flame Spraying ◽  
Knoop Microhardness ◽  
Coating Design ◽  
A Site

Abstract Statistical design-of-experiment studies of the thermal spraying of polymer powders are presented. Studies of the subsonic combustion (i.e., Flame) process were conducted in order to determine the quality and economics of polyester and urethane coatings. Thermally sprayed polymer coatings are of interest to several industries for anticorrosion applications, including the chemical, automotive, and aircraft industries. In this study, the coating design has been optimized for a site-specific application using Taguchi-type fractional-factorial experiments. Optimized coating designs are presented for the two powder systems. A substantial range of thermal processing conditions and their effect on the resultant polymer coatings is presented. The coatings were characterized by optical metallography, hardness testing, tensile testing, and compositional analysis. Characterization of the coatings yielded the thickness, bond strength, Knoop microhardness, roughness, deposition efficiency, and porosity. Confirmation testing was accomplished to verify the coating designs.

Investigation of the Influence of Kinematic and Geometric Parameters of the Thermo- Sprayer Location on the Adhesion Strength of Anti-Friction Coating

2020 ◽  
Vol 299 ◽  
pp. 902-907
Author(s):  
Alexey Yu. Rodichev ◽  
Elena N. Gryadynova ◽  
Andrey V. Gorin
Keyword(s):  
Bond Strength ◽  
Adhesion Strength ◽  
Experimental Studies ◽  
Geometric Parameters ◽  
Flame Spraying ◽  
Mathematical Apparatus ◽  
Steel Base ◽  
Gas Flame ◽  
Inertia Forces

The article presents the results of the influence of the kinematic and geometric parameters of the thermos-sprayer location on the adhesion strength of the anti-friction coating. A mathematical apparatus for calculating the inertia forces acting on an anti-friction coating particle is proposed. The results of a number of experimental studies confirming the convergence of theoretical positions are presented. As a result, dependencies have been revealed that make it possible to predict the bond strength of the anti-friction coating with the steel base during gas-flame spraying.

Strength characterization of assemblies of polymers, made by laser welding

2015 ◽  
Vol 103 (5) ◽  
pp. 503
Author(s):  
Vladimir Gantchenko ◽  
Jacques Renard ◽  
Alexander Olowinsky ◽  
Gerhard Otto
Keyword(s):  
Laser Welding ◽  
Strength Characterization

EXPERIMENTAL STUDIES ON THE CORROSION OCCURRENCE DURING BIOMASS COMBUSTION PROCESS

2012 ◽  
Vol 11 (9) ◽  
pp. 1555-1560 ◽  
Author(s):  
Ionel Pisa ◽  
Gheorghe Lazaroiu ◽  
Corina Radulescu ◽  
Lucian Mihaescu
Keyword(s):  
Combustion Process ◽  
Experimental Studies ◽  
Biomass Combustion

Synthesis and characterization of L-threonine ammonium bromide: grown on single crystal with experimental studies on NLO

2021 ◽  
Vol 44 (3) ◽  
Author(s):  
T KALAIARASI ◽  
M SENTHILKUMAR ◽  
S SHANMUGAN ◽  
T JARIN ◽  
V CHITHAMBARAM ◽  
...  
Keyword(s):  
Single Crystal ◽  
Experimental Studies ◽  
Synthesis And Characterization ◽  
Ammonium Bromide
Sign in / Sign up

Export Citation Format

Share Document