Surface and spatial flow structure of an underexpanded jet with vertical jet interactions impinging on perpendicular and inclined plates

Flow Stucture of Supersonic Underexpanded Jet With Microjets Injection

Siberian Journal of Physics ◽

10.54362/1818-7919-2013-8-1-44-55 ◽

2013 ◽

Vol 8 (1) ◽

pp. 44-55

Author(s):

Dmitriy Gubanov ◽

Valeriy Zapryagaev ◽

Nikolay Kiselev

Keyword(s):

Flow Structure ◽

Numerical Study ◽

Mixing Layer ◽

Supersonic Jet ◽

Wave Structure ◽

Streamwise Vortices ◽

Jet Mixing ◽

Underexpanded Jet ◽

Supersonic Underexpanded Jet ◽

The Impact

Experimental and numerical study of transversal microjets injection influence on the supersonic underexpanded jet flow structure has been performed. Data of measurements and calculation have acceptable agreement. Interaction of microjets with main supersonic jet sets to a decrease of an initial gasdynamic region. Microjets lead to a longitudinal streamwise vortices generation and a mushroom-like flow structures create on an external jet mixing layer. Dissipation of longitudinal streamwise vortices was observed at the second jet cell. Complex gasdynamic flow structure of the supersonic underexpanded jet interacting with supersonic microjets has been studied for the first time. This structure contains system of complex chock waves and expansion waves spreading from the position of the impact microjets/main jet localization place. Future of interaction process a chock-wave structure of main jet with additional shock waves has been studied

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Shock Motion and Flow Structure of an Underexpanded Jet in the Helical Mode

AIAA Journal ◽

10.2514/1.j058024 ◽

2019 ◽

Vol 57 (9) ◽

pp. 3943-3953 ◽

Cited By ~ 2

Author(s):

Xiangru Li ◽

Feng He ◽

Xiwen Zhang ◽

Pengfei Hao ◽

Zhaohui Yao

Keyword(s):

Flow Structure ◽

Underexpanded Jet ◽

Shock Motion ◽

Helical Mode

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Analyses of Gas Stratification Erosion by a Vertical Jet in Presence of an Obstacle Using the GOTHIC Code

Journal of Nuclear Engineering and Radiation Science ◽

10.1115/1.4046296 ◽

2020 ◽

Vol 6 (2) ◽

Author(s):

Michele Andreani ◽

Ralf Kapulla ◽

Stephan Kelm ◽

Domenico Paladino ◽

Sidharth Paranjape

Keyword(s):

Boundary Conditions ◽

Flow Structure ◽

Reference Model ◽

Initial Conditions ◽

Mixing Time ◽

State Tests ◽

Impingement Plate ◽

Image Velocimetry ◽

Sensitivity Studies ◽

Vertical Jet

Abstract The GOTHIC code was validated using three experiments carried out in the PANDA facility in the framework of the OECD/NEA HYMERES project. These tests addressed the mixing of an initially stratified atmosphere by means of a vertical jet in the presence of on obstacle (circular plate). This paper reports on the simulations of three experiments, and complementary, quasi-steady-state tests without stratification, where the flow structure above the impingement plate could be observed by means of particle image velocimetry (PIV) velocity measurements in a region larger than that considered in the transient experiments. Moreover, simulations of similar tests without obstacle conducted during the OECD/SETH-2 project are also discussed. The reference, best-estimate model used for the analyses of the three experiments with different flowrates and initial and pressure boundary conditions was built on the base of a multistep approach. This was based on mesh and modeling sensitivity studies mostly performed for the complementary tests, to assess the capability to represent the flow structure produced by the jet–plate interaction with different meshes around the plate. Generally, the results show that the use of a coarse mesh and the standard k–ε turbulence model permits a reasonable representation of the erosion process, but with a systematic over prediction of the mixing time. The results with the reference model were more accurate for two experiments with two flowrates and same initial conditions and all complementary tests. For the third test with different initial and boundary conditions, however, poor results were obtained with the reference model, which could only be improved by further refining the mesh. These results indicate that a model “qualified” for certain conditions could be inadequate for other cases, and sensitivity studies are necessary for the specific conditions considered in the analyses.

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Analyses of Gas Stratification Erosion by a Vertical Jet in Presence of an Obstacle Using the GOTHIC Code

Volume 6B: Thermal-Hydraulics and Safety Analyses ◽

10.1115/icone26-82360 ◽

2018 ◽

Author(s):

Michele Andreani ◽

Ralf Kapulla

Keyword(s):

Boundary Conditions ◽

Flow Structure ◽

Reference Model ◽

Initial Conditions ◽

Mixing Time ◽

Flow Rates ◽

State Tests ◽

Impingement Plate ◽

Sensitivity Studies ◽

Vertical Jet

The GOTHIC code was validated using three experiments carried out in the PANDA facility in the framework of the OECD/NEA project HYMERES. These tests addressed the mixing of an initially stratified atmosphere by means of a vertical jet in the presence of on obstacle (circular plate). This paper reports on the simulations of three experiments, and complementary, quasi-steady state tests without stratification, where the flow structure above the impingement plate could be observed by means of PIV velocity measurements in a region larger than that considered in the transient experiments. Moreover, simulations of similar tests without obstacle conducted during the OECD/SETH-2 are also discussed. The reference, best-estimate model used for the analyses of the three experiments with different flow rates and initial and pressure boundary conditions was built on the base of a multi-step approach. This was based on mesh and modelling sensitivity studies mostly performed for the complementary tests, to assess the capability to represent the flow structure produced by the jet-plate interaction with different meshes around the plate. Generally, the results show that the use of a coarse mesh and the standard k-ε turbulence model permits a reasonable representation of the erosion process, but with a systematic over prediction of the mixing time. The results with the reference model were more accurate for two experiments with two flow rates and same initial conditions and all complementary tests. For the third test with different initial and boundary conditions, however, poor results were obtained with the reference model, which could only be improved by further refining the mesh. These results indicate that a model “qualified” for certain conditions could be inadequate for other cases, and sensitivity studies are necessary for the specific conditions considered in the analyses.

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