Jet stability and wall impingement flow field in a thermal striping experiment

2012 ◽

Cited By ~ 3

Author(s):

Qian Yang ◽

Yuzhen Lin ◽

Quanhong Xu ◽

Chi Zhang ◽

Chih-Jen Sung

Keyword(s):

Flow Field ◽

Infrared Camera ◽

Main Stream ◽

Internal Cooling ◽

Complex Flows ◽

Cooling Effectiveness ◽

Wall Impingement ◽

Experimental Approaches ◽

Cooling Methods

In order to solve the cooling problem of aeroengine, a variety of highly efficient cooling methods came into application, such as effusion wall, impingement/effusion wall, etc. The impingement/effusion cooling methods with and without turbulence promoter ribs are introduced here. In the impingement/promoter ribs/effusion walls, turbulence promoter ribs are on the coolant side of effusion wall so as to enhance the internal cooling. Numerical and experimental approaches were taken to study cooling effectiveness of impingement/effusion liners cooling with and without turbulence promoter ribs. Cooling effectiveness of the two types cooling configurations were investigated on the same hot and cold air condition of inlet. Infrared camera was used to measure the temperature of effusion cooled surfaces on the side of hot main stream. The results showed double wall cooling with turbulence promoter ribs achieves higher cooling effectiveness than impingement/effusion cooling configurations. In addition, the two test configurations were investigated numerically to get clearer characterization of flow field in the double walls cooling configurations. High velocity vectors were found in the flow field within the gap of the double walls. A heat transfer enhancement was resulted in complex flows and increased area caused by the inclined holes and turbulence promoter ribs.

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Liquid Jet Stability in a Laminar Flow Field

Chemical Engineering & Technology ◽

10.1002/1521-4125(200205)25:5<499::aid-ceat499>3.0.co;2-u ◽

2002 ◽

Vol 25 (5) ◽

pp. 499-506 ◽

Cited By ~ 26

Author(s):

C. Cramer ◽

B. Berüter ◽

P. Fischer ◽

E. J. Windhab

Keyword(s):

Laminar Flow ◽

Flow Field ◽

Liquid Jet ◽

Jet Stability

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Electrohydrodynamic Direct-Writing Micropatterns with Assisted Airflow

Micromachines ◽

10.3390/mi9090456 ◽

2018 ◽

Vol 9 (9) ◽

pp. 456 ◽

Cited By ~ 8

Author(s):

Jiaxin Jiang ◽

Xiang Wang ◽

Wenwang Li ◽

Juan Liu ◽

Yifang Liu ◽

...

Keyword(s):

High Resolution ◽

Flow Field ◽

Structure Design ◽

Direct Writing ◽

Position Accuracy ◽

Positioning Errors ◽

Jet Stability ◽

Series Of Experiments ◽

Printed Patterns ◽

Deposition Position

Electrohydrodynamic direct-writing (EDW) is a developing technology for high-resolution printing. How to decrease the line width and improve the deposition accuracy of direct-written patterns has been the key to the promotion for the further application of EDW. In this paper, an airflow-assisted spinneret for electrohydrodynamic direct-writing was designed. An assisted laminar airflow was introduced to the EDW process, which provided an additional stretching and constraining force on the jet to reduce the surrounding interferences and enhance jet stability. The flow field and the electric field around the spinneret were simulated to direct the structure design of the airflow-assisted spinneret. Then, a series of experiments were conducted, and the results verified the spinneret design and demonstrated a stable ejection of jet in the EDW process. With assisted airflow, the uniformity of printed patterns and the deposition position accuracy of a charged jet can be improved. Complex patterns with positioning errors of less than 5% have been printed and characterized, which provide an effective way to promote the integration of micro/nanosystems.

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Detailed measurements of the flow field in vaneless and vaned diffusers of centrifugal compressors

Journal de Physique III ◽

10.1051/jp3:1992213 ◽

1992 ◽

Vol 2 (9) ◽

pp. 1787-1804 ◽

Cited By ~ 2

Author(s):

Christian Fradin

Keyword(s):

Flow Field ◽

Centrifugal Compressors

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Numerical Study of the Combined Free-Forced Convection and Mass Transfer Flow Past a Vertical Porous Plate in a Porous Medium with Heat Generation and Thermal Diffusion

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2006.11.4.14737 ◽

2006 ◽

Vol 11 (4) ◽

pp. 331-343 ◽

Cited By ~ 19

Author(s):

M. S. Alam ◽

M. M. Rahman ◽

M. A. Samad

Keyword(s):

Mass Transfer ◽

Flow Field ◽

Differential Equations ◽

Forced Convection ◽

Heat Generation ◽

Numerical Study ◽

Porous Plate ◽

Integration Scheme ◽

Suction Parameter ◽

Transfer Flow

The problem of combined free-forced convection and mass transfer flow over a vertical porous flat plate, in presence of heat generation and thermaldiffusion, is studied numerically. The non-linear partial differential equations and their boundary conditions, describing the problem under consideration, are transformed into a system of ordinary differential equations by using usual similarity transformations. This system is solved numerically by applying Nachtsheim-Swigert shooting iteration technique together with Runge-Kutta sixth order integration scheme. The effects of suction parameter, heat generation parameter and Soret number are examined on the flow field of a hydrogen-air mixture as a non-chemical reacting fluid pair. The analysis of the obtained results showed that the flow field is significantly influenced by these parameters.

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