High performance flow field visualization with high-order access dependencies

An experimental investigation concerning tip flow field unsteadiness was performed for a high-performance, state-of-the-art transonic compressor rotor. Casing-mounted high frequency response pressure transducers were used to indicate both the ensemble averaged and time varying flow structure present in the tip region of the rotor at four different operating points at design speed. The ensemble averaged information revealed the shock structure as it evolved from a dual shock system at open throttle to an attached shock at peak efficiency to a detached orientation at near stall. Steady three-dimensional Navier Stokes analysis reveals the dominant flow structures in the tip region in support of the ensemble averaged measurements. A tip leakage vortex is evident at all operating points as regions of low static pressure and appears in the same location as the vortex found in the numerical solution. An unsteadiness parameter was calculated to quantify the unsteadiness in the tip cascade plane. In general, regions of peak unsteadiness appear near shocks and in the area interpreted as the shock-tip leakage vortex interaction. Local peaks of unsteadiness appear in mid-passage downstream of the shock-vortex interaction. Flow field features not evident in the ensemble averaged data are examined via a Navier-Stokes solution obtained at the near stall operating point.

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Visualization of Internal Flow Field of Propeller Fan

Volume 1A, Symposia: Keynotes; Advances in Numerical Modeling for Turbomachinery Flow Optimization; Fluid Machinery; Industrial and Environmental Applications of Fluid Mechanics; Pumping Machinery ◽

10.1115/fedsm2017-69261 ◽

2017 ◽

Author(s):

Takaya Onishi ◽

H. Sato ◽

M. Hayakawa ◽

Y. Kawata

Keyword(s):

Flow Field ◽

High Performance ◽

Laser Light ◽

Internal Flow ◽

Light Sheet ◽

Tip Vortex ◽

Laser Light Sheet ◽

Blade Surface ◽

Similar Tendency ◽

Flow Phenomena

Propeller fans are required not only to have high performance but also to be extremely quiet. The internal flow field of ventilation propeller fans is even more complicated because they usually have a very peculiar configuration with protruding blades upstream. Thus, many kinds of internal vortices yield which cause noise and their cause and countermeasures are needed to be clarified. The purposes of this paper are to visualize the internal flow of the propeller fan from the static and rotating frame of reference. The internal flow visualization measured from the static frame gives approximately the scale of the tip vortex. The visualization from the rotating coordinate system yields a better understanding of the flow phenomena occurring at the specific blade. The experiment is implemented by using a small camera mounted on the shaft of the fan and rotated it to capture the behavior of the vortices using a laser light sheet to irradiate the blade surface. Hence, the flow field of the specific blade could be understood to some extent. The visualized results are compared with the CFD results and these results show a similar tendency about the generation point and developing process of the tip vortex. In addition, it is found that the noise measurement result is relevant to the effect of tip vortex from the visualization result.

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Numerical Simulation of Flow in Imported Steam Turbine Inlet Components with Equilibrated Holes in High Performance

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.1263 ◽

2013 ◽

Vol 712-715 ◽

pp. 1263-1267

Author(s):

Shan Tu ◽

Shu Ming Wu ◽

Qi Zhou ◽

Hong Mei Zhang ◽

Xiao Qing Zhu

Keyword(s):

Flow Field ◽

Steam Turbine ◽

High Performance ◽

Optimization Design ◽

Great Influence ◽

Control Valve ◽

Stable Operation ◽

Valve Seat ◽

Valve Disc ◽

Interior Flow

The main inlet component of steam turbine is control valve. The stable operation of the steam turbine control valve is vital for safe and stable operation of the steam turbine and safety production of the power plant. However, due to the complexity of the structure and unsteady characteristics of steam flow in the valve, there is not enough experimental method about the detailed flow characteristics of the area near control valve disc and the inside of the valve chamber up to now. This article is to focus on the simulation of the steam turbine control valve interior flow field which includes the valve pre-inlet channel in different conditions, then find the reasons which caused instability and pressure loss of the control valve by analyzing the flow field details, finally further optimization design. The profile matching of the valve disc and valve seat has a great influence on the interior flow field of control valve, so analysis of the high performance valve disc shape and divergence angle of valve seat is carried out, and the research conclusion is used for guide design and development of the control valve.

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Research on CFD Simulation of the Cement Slurry Mixer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.621.196 ◽

2012 ◽

Vol 621 ◽

pp. 196-199

Author(s):

Shui Ping LI ◽

Ya Li Yuan ◽

Lu Gang Shi

Keyword(s):

Flow Field ◽

High Performance ◽

Cfd Simulation ◽

Structural Parameters ◽

Internal Flow ◽

Simulation Method ◽

Cement Slurry ◽

Fluid Machinery ◽

Computational Fluid Dynamics Cfd ◽

Machinery Design

Numerical simulation method of the internal flow field of fluid machinery has become an important technology in the study of fluid machinery design. In order to obtain a high-performance cement slurry mixer, computational fluid dynamics (CFD) techniques are used to simulate the flow field in the mixer, and the simulation results are studied. According to the analysis results, the structural parameters of the mixer are modified. The results show the mixer under the revised parameters meet the design requirements well. So CFD analysis method can shorten design period and provide valuable theoretical guidance for the design of fluid machinery.

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