FLOW ON THE LEEWARD SIDE OF A SUPERSONIC SOURCE IN A SUPERSONIC STREAM International Space Science Institute Team Meeting “Modeling Cometary Environments in the Context of the Heritage of the Giotto Mission to Comet Halley” 19—24 November, 2012 M. G. LEBEDEV
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FLOW ON THE LEEWARD SIDE OF A SUPERSONIC SOURCE IN A SUPERSONIC STREAM
International Space Science Institute Team Meeting “Modeling Cometary Environments in the Context of the Heritage of the Giotto Mission to Comet Halley” 19—24 November, 2012. FLOW ON THE LEEWARD SIDE OF A SUPERSONIC SOURCE IN A SUPERSONIC STREAM. M. G. LEBEDEV. - PowerPoint PPT Presentation
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FLOW ON THE LEEWARD SIDE OF A SUPERSONIC SOURCE IN A
SUPERSONIC STREAM
International Space Science Institute
Team Meeting “Modeling Cometary Environments in the Context of the Heritage of the Giotto Mission to Comet
Halley”
19—24 November, 2012
M. G. LEBEDEV
• Unexpected and interesting phenomena can occur on the leeward (night) side of a comet in the solar wind flow. One of these phenomena can be the formation of return (circulatory) flow zones.
• The results of Dr. Benna’s simulation hint at this possibility
Calculation using the Babenko—Rusanov method (1980)
Calculation of supersonic flow past a supersonic source (windward side)
Formulation of the problem in the tail flow region
Streamlines General flow pattern
Velocity profile along the axis of symmetry
.
Calculation of the flow on the leeward side using the Godunov method
Longitudinal velocity and pressure distributions in the X = 39 section
Hydrogen burns behind a cylindrical stabilizer, G.Winterfeld,1968.
Formation of return flow zones on reflection of an incident Formation of return flow zones on reflection of an incident shock from the axis of symmetry in a wake-type flowshock from the axis of symmetry in a wake-type flow
Low-pressure jetlet in a supersonic Low-pressure jetlet in a supersonic underexpanded jetunderexpanded jet
B.J. Gribben, K.J. Badcock, B.E. Richards. Numerical study of shock-reflection hysteresis in an underexpanded jet // AIAA Journal. 2000. V. 38. N. 2. P. 275—283.
M. Frey. Behandlung von Strömungsproblem in Racketendüsen bei Überexpansion // Inst. für Aerodynamik und Gasdynamik, Univ. Stuttgart. Dr.-Ing. Diss. 2001. (http://elib.uni-stuttgart.de/opus/volltexte/2001/800/pdf/diss_frey.pdf)
В.А. Горяйнов. О возможности реверса течения в свободных сверхзвуковых струях // Мат. моделирование. 2003. Т. 15. № 7. С. 86—92.
О.В. Бочарова, М.Г. Лебедев, А.В. Савин, Е.И. Соколов. Стационарные циркуляционные зоны в сверхзвуковых неравномерных потоках // XXI Школа-семинар ЦАГИ «Аэродинамика летательных аппаратов». Тезисы докладов М.: Изд. ЦАГИ. 2010. С. ??--??.
The existence of these experimentally observed structures was confirmed in numerical calculations.
So far, in the case of the source-type nonuniformity analogous structures were obtained only in numerical experiments
The problem of supersonic spherical source flow in a cylindrical channel
Calculated flow pattern at gamma = 1.4
Calculated flow pattern atgamma = 1.05
Calculations by the AAV method
Source flow with nonuniform angular velocity distribution (a maximum velocity is reached at the channel axis). The initial data correspond to the case of “uniform” source (gamma = 1.1). The return flow zone disappears.
In this case the velocity on the axis is minimum. As a result, the return flow zone enlarges.