scholarly journals Deformation and removal of viscous thin film by submerged jet impingement

AIChE Journal ◽  
2019 ◽  
Vol 66 (1) ◽  
Author(s):  
Jiakai Lu ◽  
Carlos M. Corvalan ◽  
Jen‐Yi Huang
Keyword(s):  
Thin Film ◽  
Jet Impingement ◽  
Submerged Jet

Submerged Jet Impingement Cooling of a Nanostructured Plate

2010 ◽  
Author(s):  
Muhsincan Sesen ◽  
Ali Kosar ◽  
Ebru Demir ◽  
Evrim Kurtoglu ◽  
Nazli Kaplan ◽  
...  
Keyword(s):  
Thin Film ◽  
Heat Transfer ◽  
Heat Flux ◽  
Silicon Wafer ◽  
Heat Removal ◽  
Jet Impingement ◽  
Wafer Surface ◽  
Small Scale ◽  
Copper Thin Film ◽  
Thin Film Layer

In this paper, the results of a series of heat transfer experiments conducted on a compact electronics cooling device based on single phase jet impingement techniques are reported. Deionized-water is propelled into four microchannels of inner diameter 685 μm which are used as nozzles and located at a nozzle to surface distance of 2.5mm. The generated jet impingement is targeted through these channels towards the surface of a nanostructured plate. This plate of size 20mmx20mm consisted of ∼600 nm long copper nanorod arrays with an average nanorod diameter of ∼150 nm, which were integrated on top of a silicon wafer substrate coated with a copper thin film layer (i.e. Cu-nanorod/Cu-film/Silicon-wafer). Heat removal characteristics induced through jet impingement are investigated using the nanostructured plate and compared to results obtained from a flat plate of copper thin film coated on silicon wafer surface. Enhancement in heat transfer up to 15% using the nanostructured plate has been reported in this paper. Heat generated by small scale electronic devices is simulated using a thin film heater placed on an aluminum base. Surface temperatures are recorded by a data acquisition system with the thermocouples integrated on the surface at various locations. Constant heat flux provided by the film heater is delivered to the nanostructured plate placed on top of the base. Volumetric flow rate and heat flux values were varied in order to better characterize the potential enhancement in heat transfer by nanostructured surfaces.

Confined Submerged Jet Impingement Boiling of Subcooled FC-72 over Micro-Pin-Finned Surfaces

2015 ◽  
Vol 37 (3-4) ◽  
pp. 269-278 ◽  
Author(s):  
Yonghai Zhang ◽  
Jinjia Wei ◽  
Xin Kong ◽  
Ling Guo
Keyword(s):  
Jet Impingement ◽  
Submerged Jet ◽  
Jet Impingement Boiling

Submerged Jet Impingement Boiling on a Polished Silicon Surface

2011 ◽  
Author(s):  
Preeti Mani ◽  
Ruander Cardenas ◽  
Vinod Narayanan
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Reynolds Number ◽  
Silicon Surface ◽  
High Speed ◽  
Jet Impingement ◽  
Working Fluid ◽  
Uniform Heat Flux ◽  
Submerged Jet ◽  
Jet Impingement Boiling

Submerged jet impingement boiling has the potential to enhance pool boiling heat transfer rates. In most practical situations, the surface could consist of multiple heat sources that dissipate heat at different rates resulting in a surface heat flux that is non-uniform. This paper discusses the effect of submerged jet impingement on the wall temperature characteristics and heat transfer for a non-uniform heat flux. A mini-jet is caused to impinge on a polished silicon surface from a nozzle having an inner diameter of 1.16 mm. A 25.4 mm diameter thin-film circular serpentine heater, deposited on the bottom of the silicon wafer, is used to heat the surface. Deionized degassed water is used as the working fluid and the jet and pool are subcooled by 20°C. Voltage drop between sensors leads drawn from the serpentine heater are used to identify boiling events. Heater surface temperatures are determined using infrared thermography. High-speed movies of the boiling front are recorded and used to interpret the surface temperature contours. Local heat transfer coefficients indicate significant enhancement upto radial locations of 2.6 jet diameters for a Reynolds number of 2580 and upto 6 jet diameters for a Reynolds number of 5161.

On jet impingement and thin film breakup on a horizontal superhydrophobic surface

2015 ◽  
Vol 27 (11) ◽  
pp. 112108 ◽  
Author(s):  
Joseph F. Prince ◽  
Daniel Maynes ◽  
Julie Crockett
Keyword(s):  
Thin Film ◽  
Superhydrophobic Surface ◽  
Jet Impingement

scholarly journals THE PREFERENTIAL WELD CORROSION OF X65 CARBON STEEL PIPELINE UNDER CO2 ENVIRONMENT

2020 ◽  
Vol 42 (1) ◽  
pp. 15-28
Author(s):  
Nofrizal Nofrizal
Keyword(s):  
Weld Metal ◽  
Flow Rate ◽  
Heat Affected Zone ◽  
Pipeline Steel ◽  
Jet Impingement ◽  
Corrosion Process ◽  
Corrosion Mechanism ◽  
Submerged Jet ◽  
Corrosion Rates ◽  
Weld Corrosion

Preferential weld corrosion (PWC) is a severe corrosion form of attack found in pipeline weldments in oil and gas industries. PWC occurs when the corrosion rate of the weld metal (WM) and heat affected zone (HAZ) is higher than the parent metal (PM). PWC was generated by galvanic corrosion mechanism due to dissimilarities in the composition and microstructure of the metal in the three weld regions.The aim of this research is to study the effect of flow rate on preferential weld corrosion (PWC) in X65 high strength pipeline steel using submerged jet impingement by investigating the mechanism of PWC on a weldment in artificial seawater saturated with carbon dioxide at 1 bar. A novel submerged jet impingement apparatus that consist of 3 rings (outer, inner and centre) was designed so that the parent material, heat affected zone and weld metal could be analysed in a high shear stress environment. Corrosion experiments were performed with X65 pipeline steel under no flow and flowing condition at 10 m/s at 30oC and pH4. The galvanic current characteristic between the weldment regions was recorded using a zero-resistance ammeter, and the self-corrosion was analysed by using linear polarisation resistance measurements. Total corrosion rates were calculated from the sum of the galvanic and self-corrosion contributions. The morphology, structure, chemical on the surface of X65 after corrosion process was investigated by means of scanning electron microscopy (SEM) and focus ion beam (FIB) to examine the corrosion product that form in brine containing dissolved carbon dioxide.In a no-flow condition, the result shows that the galvanic characteristics on all weldments were similar and the WM is cathodic and protected in comparison with the HAZ and PM. In flowing condition, the estimated flow rates associated with the different positions on the target vary depending on either (a) PM and HAZ or (b) the WM. The effects of target flow rate on WM have a similar trend, but the overall corrosion rates are greater due to PWC. The result of surface analysis after corrosion process showing that removal of hardened layer and subsurface cracking were causes of enhanced degradation.

Critical Heat Flux During Submerged Jet Impingement Boiling of Saturated Water at Sub-Atmospheric Conditions

2011 ◽  
Author(s):  
Ruander Cardenas ◽  
Vinod Narayanan
Keyword(s):  
Experimental Data ◽  
Heat Flux ◽  
Critical Heat Flux ◽  
Jet Impingement ◽  
Atmospheric Conditions ◽  
Predictive Tool ◽  
Submerged Jet ◽  
Fluid Saturation ◽  
Saturated Water ◽  
Jet Impingement Boiling

Experimental data for critical heat flux (CHF) during submerged jet impingement boiling of saturated water at sub-atmospheric conditions is presented. Experiments are performed at three sub-atmospheric pressures of 0.176 bar, 0.276 bar, and 0.477 bar with corresponding fluid saturation temperatures of about 57.3 °C, 67.2 °C, and 80.2 °C. Jet exit Reynolds numbers ranging from 0 to 14,000 are considered for two different heater surface finishes at a fixed nozzle to surface spacing of six nozzle diameters. CHF correlations from literature on jet impingement boiling are compared against the experimental data and found to poorly predict CHF under the conditions considered. A CHF correlation that captures the entire experimental data set within an average error of ±3 percent and a maximum error of ±13 percent is developed to serve as a predictive tool for the range of conditions examined.

Effects of Fluid Viscosity and Impingement Angle on Submerged Jet Flowfields

2018 ◽  
Author(s):  
Soroor Karimi ◽  
Matthew Fulton ◽  
Siamack A. Shirazi ◽  
Brenton McLaury
Keyword(s):  
Maximum Velocity ◽  
Jet Impingement ◽  
Reynolds Numbers ◽  
Fluid Viscosity ◽  
Impingement Angle ◽  
Submerged Jet ◽  
Glass Spheres ◽  
Image Velocimetry ◽  
Computational Fluid Dynamics Cfd ◽  
Flow Experiments

Many researchers have utilized submerged jet impingement geometry to study solid particle erosion/corrosion. However, only a few studies have investigated changing impingement angle and fluid viscosity. In this study, Particle Image Velocimetry (PIV) experiments were conducted using 14 micron glass spheres for direct impingement geometry at viscosities of 1, 14, and 55 cP. These viscosities correspond to Reynolds numbers of approximately 57000, 4000, and 1000, respectively. It was observed that by increasing the viscosity the flow exiting the nozzle transitioned from extremely turbulent to laminar flow. The data indicated fully turbulent flow at the outlet for viscosities of 1 and 14 cP. In the case of 55 cP flow, the flow exiting the nozzle became laminar contributing to a higher maximum velocity in 55 cP flow. Experiments at these viscosities were also conducted at impingement angles of 90, 75, and 45 degrees to investigate the effects of the impinging jet angle on a flat plate. Additionally, a series of Computational Fluid Dynamics (CFD) simulations of the flowfield were performed to compare with the experimental data collected in this paper.

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