High Temperature

, Volume 57, Issue 3, pp 388–392 | Cite as

Simple Wave Transformations in the Channel

  • L. N. PyatnitskyEmail author


The Riemann wave describes the plane flow behind an infinite wavefront, though it is used to describe its propagation in channels. The influence of the walls on the process of wave propagation is not taken into account. However, friction against the walls slows the flow, and the limited diameter of the elementary plane waves, which compensate for the friction, undergo diffraction divergence. As a result, the entropy constancy and laminar flow structure are violated. This means that a simple wave as such may not exist in the channel. In this case, analysis of the friction and diffraction divergence make it possible to explain the turbulence occurrence in the flow and to find a way to form a simple wave of finite aperture with a large Rayleigh length.



The article was translated by the author.


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Copyright information

© Pleiades Publishing, Ltd. 2019

Authors and Affiliations

  1. 1.Joint Institute for High Temperature, Russian Academy of SciencesMoscowRussia

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