The underexpanded microjet emerging from a rectangular convergent nozzle with a high aspect ratio at the nozzle exit is investigated numerically using the Reynolds-averaged Navier-Stokes (RANS) simulation with the Menter’s shear stress transport (SST) k-ω turbulence model. The simulation is performed at the nozzle pressure ratio of 5.0 to produce a strong shock and it is validated by a comparison with a rainbow schlieren picture of the microjet. The three-dimensional structure of the shock-containing rectangular microjet is demonstrated using the isopycnic surface and bright-field schlieren representations.
References
[1]
Kweon, Y.H. and Kim, H.D. (2011) Study on the Wiping Gas Jet in Continuous Galvanizing Line. Journal of Thermal Science, 20, 242-247. https://doi.org/10.1007/s11630-011-0465-6
[2]
Kashimura, H., Masuda, Y., Miyazato, Y. and Matsuo, K. (2011) Numerical Analysis of Turbulent Sonic Jets from Two-Dimensional Convergent Nozzles. Journal of Thermal Science, 20, 133-138. https://doi.org/10.1007/s11630-011-0447-8
[3]
Handa, T., Mii, K., Sakurai, T., Imamura, K., Mizuta, S. and Ando, Y. (2014) Study on Supersonic Rectangular Microjets Using Molecular Tagging Velocimetry. Experiments in Fluids, 55, 1725. https://doi.org/10.1007/s00348-014-1725-5
[4]
Aniskin, V.M., Maslov, A.A., Tsirulnikov, I.S. and Timofeev, I.V. (2015) Visualization of Supersonic Axisymmetric and Plane Underexpanded Microjets. Journal of Flow Visualization & Image Processing, 22, 213-227. https://doi.org/10.1615/JFlowVisImageProc.2016016429
[5]
Aniskin, V.M., Maslov, A.A., Mironov, S.G., Tsyryulnikov, I.S. and Timofeev, I.V. (2015) An Experimental Study of the Structure of Supersonic Flat Underexpanded Microjets. Technical Physics Letters, 41, 508-510. https://doi.org/10.1134/S106378501505017X
[6]
Aniskin, V.M., Timofeev, I.V., Maslov, N.A. and Tsibulskaya, E.O. (2019) Effect of the Pitot Microtube Diameter on Pressure Measurement in Plane Supersonic Microjets. Flow Measurement and Instrumentation, 70, 101655. https://doi.org/10.1016/j.flowmeasinst.2019.101655
[7]
Franquet, E., Perrier, V., Gibout, S. and Bruel, P. (2015) Free Underexpanded Jets in a Quiescent Medium: A Review. Progress in Aerospace Sciences, 77, 25-53. https://doi.org/10.1016/j.paerosci.2015.06.006
[8]
Fukunaga, R., Ezoe, M., Nakao, S. and Miyazato, Y. (2022) Application of Rainbow Schlieren Tomography for Shock-Containing Rectangular Jets. Journal of Visualization, 25, 687-695. https://doi.org/10.1007/s12650-022-00827-w
[9]
Nagata, T., Islam, M.M., Miyaguni, T., Nakao, S. and Miyazato, Y. (2022) Shock-Cell Spacings of Underexpanded Sonic Jets Emerging from Elliptic Nozzles. Experiments in Fluids, 63, 111. https://doi.org/10.1007/s00348-022-03463-0
[10]
Tashiro, T., Fukunaga, R., Utsunomiya, D., Nakao, S., Miyazato, Y. and Ishino, Y. (2023) Flow Features of Underexpanded Microjets Emerging from a Round Convergent Nozzle. Experiments in Fluids, 64, 55. https://doi.org/10.1007/s00348-023-03603-0
[11]
Sugawara, S., Nakao, S., Miyazato, Y., Ishino, Y. and Miki, K. (2020) Three-Dimensional Reconstruction of a Microjet with a Mach Disk by Mach-Zehnder Interferometers. Journal of Fluid Mechanics, 893, A25. https://doi.org/10.1017/jfm.2020.217
[12]
Sugawara, S., Nakao, S., Miyazato, Y., Ishino, Y. and Miki, K. (2020) Quantitative Flow Visualization of Slightly Underexpanded Microjets by Mach-Zehnder Interferometers. Flow, Turbulence and Combustion, 106, 971-992. https://doi.org/10.1007/s10494-020-00211-4
[13]
Maeno, K., Kaneta, T., Morioka, T. and Honma, H. (2005) Pseudo-Schlieren CT Measurement of Three-Dimensional Flow Phenomena on Shock Waves and Vortices Discharged from Open Ends. Shock Waves, 14, 239-249. https://doi.org/10.1007/s00193-005-0256-7
[14]
Settles, G.S. and Hargather, M.J. (2017) A Review of Recent Developments in Schlieren and Shadowgraph Techniques. Measurement Science and Technology, 28, 042001. https://doi.org/10.1088/1361-6501/aa5748
