Laser Doppler Field Sensor for Two Dimensional Flow Measurements in Three Velocity Components

2009 ◽  
pp. 21-30 ◽  
Author(s):  
Andreas Voigt ◽  
Christoph Skupsch ◽  
Jörg König ◽  
Katsuaki Shirai ◽  
Lars Büttner ◽  
...  
Keyword(s):  
Laser Doppler ◽  
Two Dimensional ◽  
Flow Measurements ◽  
Dimensional Flow ◽  
Two Dimensional Flow ◽  
Field Sensor

A note on turbulent shear-layer reattachment downstream of a backward-facing step in confined supersonic two-dimensional flow

1971 ◽  
Vol 46 (2) ◽  
pp. 293-297 ◽  
Author(s):  
T. Mukerjee ◽  
A. Farshi ◽  
B. W. Martin
Keyword(s):  
Free Stream ◽  
Supersonic Jet ◽  
Surface Flow ◽  
Turbulent Shear ◽  
Two Dimensional ◽  
Flow Measurements ◽  
Turbulent Shear Layer ◽  
Dimensional Flow ◽  
Two Dimensional Flow ◽  
Free Stream Mach Number

The reattachment of a supersonic jet with a turbulent separating boundary layer abruptly expanding into a two-dimensional parallel diffuser has been experimentally investigated using a surface-flow technique. The reattachment criterion proposed by Mukerjee & Martin (1969) for axisymmetric confined and unconfined flows is found to correlate equally well similar two-dimensional flow measurements in terms of the free-stream Mach number after separation.

scholarly journals Intraindividual validation of 4D flow measurement against 2D flow measurements in complex flow patterns in routine clinical cardiovascular magnetic resonance of bicuspid aortic valve

2020 ◽  
Vol 51 (1) ◽  
Author(s):  
Ahmed Kharabish ◽  
Kristina Belker ◽  
Stefan Martinoff ◽  
Peter Ewert ◽  
Anja Hennemuth ◽  
...  
Keyword(s):  
Aortic Valve ◽  
Flow Pattern ◽  
Bicuspid Aortic Valve ◽  
Flow Measurement ◽  
Two Dimensional ◽  
Complex Flow ◽  
Flow Measurements ◽  
Dimensional Flow ◽  
Dimensional Measurements ◽  
Two Dimensional Flow

Abstract Background Comparing four-dimensional flow against two-dimensional flow measurements in patients with complex flow pattern is still lacking. This study aimed to compare four-dimensional against the two-dimensional flow measurement in patients with bicuspid aortic valve and to test potentials of four-dimensional operator-dependent sources of error. Results The two- and four-dimensional flow data sets of sixteen patients with bicuspid aortic valve and eighteen healthy subjects were studied. Flow analyses were performed by two observers blindly. Patients with bicuspid aortic valve mean differences between the two- and four-dimensional measurements in both observers were − 8 and − 4 ml, respectively. Four-dimensional measurements resulted in systematically higher flow values than the two-dimensional flow in bicuspid aortic valve patients. The upper and lower limits of agreement between the two- and four-dimensional measurements by both observers were + 12/− 28 ml and + 14/− 21 ml, respectively. In the healthy volunteers, mean differences between the two- and four-dimensional measurements in both observers were ± 0 and + 1 ml, respectively. The upper and lower limits of agreement between the two- and four-dimensional measurements by both observers were + 21/− 18 ml and + 12/− 13 ml, respectively. Inter-observer variability in four-dimensional flow measurement was 4% mean net forward flow in bicuspid aortic valve patients and 8% in healthy volunteers. Conclusion Inter-observer variability in four-dimensional flow assessment is 8% or less which is acceptable for clinical cardiac MRI routine. There is close agreement of two- and four-dimensional flow tools in normal and complex flow pattern. In complex flow pattern, however, four-dimensional flow measurement picks up 4–9% higher flow values. It seems, therefore, that four-dimensional flow is closer to real flow values than two-dimensional flow, which is however to be proven by further studies.

Two-Dimensional Flow of Polymer Solutions Through Porous Media

1999 ◽  
Vol 2 (3) ◽  
pp. 251-262
Author(s):  
P. Gestoso ◽  
A. J. Muller ◽  
A. E. Saez
Keyword(s):  
Porous Media ◽  
Polymer Solutions ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Two Dimensional Flow

STUDY OF NON-ISOTHERMAL TWO-DIMENSIONAL FLOW OVER A SQUARE CYLINDER IMMERSED IN A CHANNEL

2019 ◽  
Author(s):  
Gabriel Machado dos Santos ◽  
Ítalo Augusto Magalhães de Ávila ◽  
Hélio Ribeiro Neto ◽  
João Marcelo Vedovoto
Keyword(s):  
Two Dimensional ◽  
Square Cylinder ◽  
Dimensional Flow ◽  
Two Dimensional Flow

scholarly journals Two-dimensional flow field distribution characteristics of flocking drainage pipes in tunnel

Open Physics ◽  
2020 ◽  
Vol 18 (1) ◽  
pp. 139-148
Author(s):  
Shiyang Liu ◽  
Xuefu Zhang ◽  
Feng Gao ◽  
Liangwen Wei ◽  
Qiang Liu ◽  
...  
Keyword(s):  
Flow Field ◽  
Field Distribution ◽  
Rapid Development ◽  
Maximum Velocity ◽  
Distribution Characteristics ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Laboratory Test Results ◽  
Transverse Distance ◽  
Two Dimensional Flow

AbstractWith the rapid development of traffic infrastructure in China, the problem of crystal plugging of tunnel drainage pipes becomes increasingly salient. In order to build a mechanism that is resilient to the crystal plugging of flocking drainage pipes, the present study used the numerical simulation to analyze the two-dimensional flow field distribution characteristics of flocking drainage pipes under different flocking spacings. Then, the results were compared with the laboratory test results. According to the results, the maximum velocity distribution in the flow field of flocking drainage pipes is closely related to the transverse distance h of the fluff, while the longitudinal distance h of the fluff causes little effect; when the transverse distance h of the fluff is less than 6.25D (D refers to the diameter of the fluff), the velocity between the adjacent transverse fluffs will be increased by more than 10%. Moreover, the velocity of the upstream and downstream fluffs will be decreased by 90% compared with that of the inlet; the crystal distribution can be more obvious in the place with larger velocity while it is less at the lower flow rate. The results can provide theoretical support for building a mechanism to deal with and remove the crystallization of flocking drainage pipes.

Contracting ducts of finite length

1951 ◽  
Vol 2 (4) ◽  
pp. 254-271 ◽  
Author(s):  
L. G. Whitehead ◽  
L. Y. Wu ◽  
M. H. L. Waters
Keyword(s):  
Stream Function ◽  
Finite Length ◽  
Velocity Potential ◽  
Three Dimensional ◽  
Relaxation Method ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Hodograph Plane ◽  
Two Dimensional Flow ◽  
Working Section

SummmaryA method of design is given for wind tunnel contractions for two-dimensional flow and for flow with axial symmetry. The two-dimensional designs are based on a boundary chosen in the hodograph plane for which the flow is found by the method of images. The three-dimensional method uses the velocity potential and the stream function of the two-dimensional flow as independent variables and the equation for the three-dimensional stream function is solved approximately. The accuracy of the approximate method is checked by comparison with a solution obtained by Southwell's relaxation method.In both the two and the three-dimensional designs the curved wall is of finite length with parallel sections upstream and downstream. The effects of the parallel parts of the channel on the rise of pressure near the wall at the start of the contraction and on the velocity distribution across the working section can therefore be estimated.

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