High-Speed Shadowgraphy Measurements of an Erosive Particle-Laden Jet Under High-Pressure Compressor Conditions

2017 ◽  
Vol 140 (1) ◽  
Author(s):  
Max Hufnagel ◽  
Christian Werner-Spatz ◽  
Christian Koch ◽  
Stephan Staudacher
Keyword(s):  
High Pressure ◽  
Dimensional Analysis ◽  
Particle Velocity ◽  
High Speed ◽  
Fluid Velocity ◽  
Measurement Techniques ◽  
Real Life ◽  
Solid Particles ◽  
Flat Plates ◽  
Erosive Change

Erosive damage done to jet engine compressor blading by solid particles has a negative influence on the compressor aerodynamic properties and hence decreases performance. The erosive change of shape has been investigated in a multitude of experiments ranging from eroding flat plates to eroding full engines. The basic challenge to transfer the results from very simple tests to real life erosion remains. Up to date measurement techniques today allow closing this gap. The necessary experimental and analytical steps are shown. The erosion resistance of Ti–6Al–4V at realistic flow conditions with fluid velocities ranging from 200 to 400 m/s is used. The erodent used was quartz sand with a size distribution corresponding to standardized Arizona Test Dust A3 (1–120 μm). Flat plates out of Ti–6Al–4V were eroded at different impingement angles. The particle velocities and sizes were investigated using a high-speed laser shadowgraphy technique. A dimensional analysis was carried out to obtain nondimensional parameters suitable for describing erosion. Different averaging methods of the particle velocity were examined in order to identify a representative particle velocity. Compared to the fluid velocity and the mean particle velocity, the energy averaged particle velocity is found to be the best representation of the erosiveness of a particle stream. The correlations derived from the dimensional analysis are capable of precisely predicting erosion rates for different rig operating points (OPs). The results can be applied to the methodology published by Schrade et al. (2015, “Experimental and Numerical Investigation of Erosive Change of Shape for High-Pressure Compressors,” ASME Paper No. GT2015-42061).

High-Speed Shadowgraphy Measurements of an Erosive Particle-Laden Jet Under High-Pressure Compressor Conditions

2017 ◽  
Author(s):  
M. Hufnagel ◽  
C. Koch ◽  
S. Staudacher ◽  
C. Werner-Spatz
Keyword(s):  
Dimensional Analysis ◽  
Particle Velocity ◽  
High Speed ◽  
Fluid Velocity ◽  
Measurement Techniques ◽  
Real Life ◽  
Negative Influence ◽  
Solid Particles ◽  
Flat Plates ◽  
Aerodynamic Properties

Erosive damage done to jet engine compressor blading by solid particles has a negative influence on the compressor aerodynamic properties and hence decreases performance. The erosive change of shape has been investigated in a multitude of experiments ranging from eroding flat plates to eroding full engines. The basic challenge to transfer the results from very simple tests to real life erosion remains. Up to date measurement techniques today allow closing this gap. The necessary experimental and analytical steps are shown. The erosion resistance of Ti-6Al-4V at realistic flow conditions with fluid velocities ranging from 200 to 400 m/s is used. The erodent used was quartz sand with a size distribution corresponding to standardized Arizona Test Dust A3 (1 to 120 μm). Flat plates out of Ti-6Al-4V were eroded at different impingement angles. The particle velocities and sizes were investigated using a high speed laser shadowgraphy technique. A dimensional analysis was carried out to obtain nondimensional parameters suitable for describing erosion. Different averaging methods of the particle velocity were examined in order to identify a representative particle velocity. Compared to the fluid velocity and the mean particle velocity, the energy averaged particle velocity is found to be the best representation of the erosiveness of a particle stream. The correlations derived from the dimensional analysis are capable of precisely predicting erosion rates for different rig operating points. The results can be applied to the methodology published in [1].

Penetration Dynamics of Solid Particles into Liquids High-Speed Experimental Results and Modelling

2005 ◽  
Vol 473-474 ◽  
pp. 429-434 ◽  
Author(s):  
Olga Verezub ◽  
György Kaptay ◽  
Tomiharu Matsushita ◽  
Kusuhiro Mukai
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Aqueous Solutions ◽  
Particle Velocity ◽  
Weber Number ◽  
High Speed ◽  
Solid Particles ◽  
Bulk Liquid ◽  
Distilled Water ◽  
Critical Weber Number

Penetration of model solid particles (polymer, teflon, nylon, alumina) into transparent model liquids (distilled water and aqueous solutions of KI) were recorded by a high speed (500 frames per second) camera, while the particles were dropped from different heights vertically on the still surface of the liquids. In all cases a cavity has been found to form behind the solid particle, penetrating into the liquid. For each particle/liquid combination the critical dropping height has been measured, above which the particle was able to penetrate into the bulk liquid. Based on this, the critical impact particle velocity, and also the critical Weber number of penetration have been established. The critical Weber number of penetration was modelled as a function of the contact angle, particle size and the ratio of the density of solid particles to the density of the liquid.

Motion of Descending Solid Particles and Local Flow Around the Particles in Downward Turbulent Water Duct Flow (Keynote)

2011 ◽  
Author(s):  
Yoshimichi Hagiwara ◽  
Hideto Fujii ◽  
Katsutoshi Sakurai ◽  
Takashi Kuroda ◽  
Atsuhide Kitagawa
Keyword(s):  
Reynolds Number ◽  
Time Scale ◽  
High Speed ◽  
Fluid Velocity ◽  
Stokes Number ◽  
Solid Particles ◽  
Duct Flow ◽  
Local Flow ◽  
Particle Reynolds Number ◽  
Turbulent Water

The Stokes number, the ratio of the particle time scale to flow time scale, is a promising quantity for estimating changes in statistics of turbulence due to particles. First, we explored the Stokes numbers in some recent studies. Secondly, we discussed the results of our direct numerical simulation for turbulent flow with a high-density particle in a vertical duct. In the discussion, we defined the particle Reynolds number from the mean fluid velocity in the near-particle region at any time. We evaluated a new local Stokes number for the particle. It is found that the Stokes number is effective for the prediction of the distance between the particle center and one wall. Finally, we carried out experiments for turbulent water flow with aluminum balls of 1 mm in diameter in a vertical channel. The motions of aluminum balls and tracer particles in the flow were captured with a high-speed video camera. We found that the experimental results for the time changes in the wall-normal distance of the ball and the particle Reynolds number for the ball are similar to the predicted results.

scholarly journals Visualisation and quantitative analysis of the near nozzle formation and structure of a high pressure water jet in air and water.

2017 ◽  
Author(s):  
Sarah Jasper ◽  
Jeanette Hussong ◽  
Ralph Lindken
Keyword(s):  
High Pressure ◽  
Fluid Velocity ◽  
Measurement Techniques ◽  
Water Jet ◽  
Rock Surface ◽  
High Speed Photography ◽  
Spray Parameters ◽  
Spatial Expansion ◽  
Potential Core ◽  
Pressure Water

High pressure water jets (HPWJ) are frequently used in industrial applications like cleaning, further processing of workpieces or cutting of materials. In a joint research program with the International Geothermal Centre (GZB) the HPWJ process is adapted to the field of rock drilling to develop and enhance an innovative drilling technology for geothermal applications. In this case, the HPWJ is used to cut and destroy rock in deep geothermal reservoirs to make them accessible for energy generation. This transfer requires a broad knowledge of the process and interaction between the HPWJ and the rock surface. The challenges in analysis and characterization of the process are high velocities of the water jet of several hundred meters per second based on the high pump pressure of up to 180 MPa and the very small spatial expansion of the field of interest between the nozzle outlet and the rock surface, which is within a few centimeters. The objective of the present work is the visualization of a HPWJ in diverse fluids as a first step to increase the process knowledge of waterjet cutting of rocks. Tests are performed in air, water and slurry respectively and a parametric study is carried out to examine the influence of different operating parameters on the HPWJ formation and structure. Moreover, the influence of the surrounding fluid on the HPWJ is investigated.Optical measurement techniques are applied to analyze the HPWJ and results will be presented. The high velocities, the very small spatial expansion and the dense liquid jet represent challenges to the application of these measurement techniques. High speed photography in terms of shadow experiments is used for visualization and relevant spray parameters are evaluated with common spray analysis techniques. Adopting the double frame technique, well-known with particle image velocimetry (PIV), an estimation of the fluid velocity on the boundary of the HPWJ is performed. In addition to the shadowgraph analysis, PIV in auto-correlation mode with fluorescent tracers is applied to analyze velocity fields, the dimension of the potential core as well as the interaction with the surrounding fluid.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4736

Study of Measurement Methods of Particle Velocity in a Spouted Bed

2012 ◽  
Vol 727-728 ◽  
pp. 1842-1847
Author(s):  
D.A. Santos ◽  
G.C. Alves ◽  
M.A.S. Barrozo ◽  
Claudio Roberto Duarte
Keyword(s):  
Particle Velocity ◽  
High Speed ◽  
Measurement Techniques ◽  
Video Camera ◽  
Three Dimensions ◽  
Average Particle ◽  
Multiphase Model ◽  
Spouted Bed ◽  
Spouted Beds ◽  
Fiber Optical

Average particle velocity measurements were carried out in a conical-cylindrical spouted bed made of acrylic. In this study an intrusive fiber optical technique which is based on a cross-correlation function between signals from its two channels was used. For a non-intrusive measurement in order to compare with the intrusive technique, images of particle movement were recorded using a high-speed video camera. The experiments were conducted in differents air velocity conditions above the minimum spouting velocity. The latter method was limited in velocity measurement only near the spouted beds wall inasmuch as the spouted bed used was a three dimensions one. On the other hand, the fiber optical is a promising technique for measuring particle velocity distributions in a three dimensions spouted bed. To predict the minimum spouting velocity in order to use this result in the measurement techniques investigation, simulations were carried out using the Eulerian-Eulerian multiphase model.

Study of Erosion on Metal Meterals for High Pressure Pipe Manifolds

2012 ◽  
Vol 155-156 ◽  
pp. 931-935
Author(s):  
Ji Xin Zhang ◽  
Jian Chun Fan ◽  
Xian Jue Zhan ◽  
Xin Jiang
Keyword(s):  
High Pressure ◽  
Failure Mechanism ◽  
High Speed ◽  
Wear Behavior ◽  
Erosive Wear ◽  
Solid Particles ◽  
Test Machine ◽  
Fracturing Fluid ◽  
Pressure Pipe ◽  
Metal Materials

The fracturing fluid with solid particles in the process of high-speed injects to high pressure pipe manifolds will cause serious erosion damage, lead to serious material loss and equipment failure. Thus the prevention of erosive wear on high pressure pipe manifolds is regarded as one of the most important problems in practical engineering. In this paper, a new type of test machine was developed to simulate the erosive wear behavior of metal materials caused by the multiphase fluid such as fracturing fluid, and study the erosion failure mechanism by various metal erosion influencing factors including the velocity of multiphase flow, solid particles of fracturing proppant and impact angles, etc. The erosion-wear experiments on 30CrMo steels used in high-pressure pipe manifolds is described in detail. Finally, the microcosmic surface testing was also used to analyze the erosion failure mechanism of metal materials for high pressure pipe manifolds.

Cyclone Bomb hits Southern Brazil in 2020

2020 ◽  
Vol 3 (3) ◽  
Author(s):  
Ricardo Gobato ◽  
Alireza Heidari
Keyword(s):  
High Pressure ◽  
Atmospheric Pressure ◽  
High Speed ◽  
Satellite Images ◽  
The State ◽  
Southern Brazil ◽  
Santa Catarina ◽  
High Area ◽  
South Of Brazil ◽  
Rapid Drop

An “explosive extratropical cyclone” is an atmospheric phenomenon that occurs when there is a very rapid drop in central atmospheric pressure. This phenomenon, with its characteristic of rapidly lowering the pressure in its interior, generates very intense winds and for this reason it is called explosive cyclone, bomb cyclone. With gusts recorded of 116 km/h, atmospheric phenomenon – “cyclone bomb” (CB) hit southern Brazil on June 30, the beginning of winter 2020, causing destruction in its influence over. One of the cities most affected was Chapecó, west of the state of Santa Catarina. The satellite images show that the CB generated a low pressure (976 mbar) inside it, generating two atmospheric currents that moved at high speed. In a northwest-southeast direction, Bolivia and Paraguay, crossing the states of Parana and Santa Catarina, and this draft that hit the south of Brazil, which caused the destruction of the affected states.  Another moving to Argentina, southwest-northeast direction, due to high area of high pressure (1022 mbar). Both enhanced the phenomenon.

YSS YXM4

Alloy Digest ◽  
2019 ◽  
Vol 68 (11) ◽  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Physical Properties ◽  
Tool Steel ◽  
High Speed ◽  
Temperature Performance

Abstract YSS YXM4 is a cobalt-alloyed molybdenum high-speed tool steel with resistance to abrasion, seizure, and deformation under high pressure. This datasheet provides information on composition, physical properties, and hardness. It also includes information on high temperature performance. Filing Code: TS-780. Producer or source: Hitachi Metals America, Ltd.

Experimental investigation of wall heat transfer due to spray combustion in a high-pressure/high-temperature vessel

2021 ◽  
pp. 146808742110072
Author(s):  
Karri Keskinen ◽  
Walter Vera-Tudela ◽  
Yuri M Wright ◽  
Konstantinos Boulouchos
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
High Pressure ◽  
High Temperature ◽  
High Speed ◽  
Transfer Problem ◽  
Wall Heat Transfer ◽  
Gas Temperature ◽  
Reference Case ◽  
High Pressure High Temperature

Combustion chamber wall heat transfer is a major contributor to efficiency losses in diesel engines. In this context, thermal swing materials (adapting to the surrounding gas temperature) have been pinpointed as a promising mitigative solution. In this study, experiments are carried out in a high-pressure/high-temperature vessel to (a) characterise the wall heat transfer process ensuing from wall impingement of a combusting fuel spray, and (b) evaluate insulative improvements provided by a coating that promotes thermal swing. The baseline experimental condition resembles that of Spray A from the Engine Combustion Network, while additional variations are generated by modifying the ambient temperature as well as the injection pressure and duration. Wall heat transfer and wall temperature measurements are time-resolved and accompanied by concurrent high-speed imaging of natural luminosity. An investigation with an uncoated wall is carried out with several sensor locations around the stagnation point, elucidating sensor-to-sensor variability and setup symmetry. Surface heat flux follows three phases: (i) an initial peak, (ii) a slightly lower plateau dependent on the injection duration, and (iii) a slow decline. In addition to the uncoated reference case, the investigation involves a coating made of porous zirconia, an established thermal swing material. With a coated setup, the projection of surface quantities (heat flux and temperature) from the immersed measurement location requires additional numerical analysis of conjugate heat transfer. Starting from the traces measured beneath the coating, the surface quantities are obtained by solving a one-dimensional inverse heat transfer problem. The present measurements are complemented by CFD simulations supplemented with recent rough-wall models. The surface roughness of the coated specimen is indicated to have a significant impact on the wall heat flux, offsetting the expected benefit from the thermal swing material.

scholarly journals Cavitation patterns in high-pressure homogenization nozzles with cylindrical orifices: Influence of mixing stream in Simultaneous Homogenization and Mixing

2021 ◽  
Author(s):  
V. Gall ◽  
E. Rütten ◽  
H. P. Karbstein
Keyword(s):  
High Pressure ◽  
Process Design ◽  
High Speed ◽  
State Of The Art ◽  
Back Pressure ◽  
High Pressure Homogenization ◽  
Unit Operation ◽  
Mixing Chamber ◽  
Cavitation Intensity ◽  
Droplet Sizes

AbstractHigh-pressure homogenization is the state of the art to produce high-quality emulsions with droplet sizes in the submicron range. In simultaneous homogenization and mixing (SHM), an additional mixing stream is inserted into a modified homogenization nozzle in order to create synergies between the unit operation homogenization and mixing. In this work, the influence of the mixing stream on cavitation patterns after a cylindrical orifice is investigated. Shadow-graphic images of the cavitation patterns were taken using a high-speed camera and an optically accessible mixing chamber. Results show that adding the mixing stream can contribute to coalescence of cavitation bubbles. Choked cavitation was observed at higher cavitation numbers σ with increasing mixing stream. The influence of the mixing stream became more significant at a higher orifice to outlet ratio, where a hydraulic flip was also observed at higher σ. The decrease of cavitation intensity with increasing back-pressure was found to be identical with conventional high-pressure homogenization. In the future, the results can be taken into account in the SHM process design to improve the efficiency of droplet break-up by preventing cavitation or at least hydraulic flip.

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