ISSN 2079-3537      

 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                                                                                             





Scientific Visualization, 2018, volume 10, number 5, pages 160 - 171, DOI: 10.26583/sv.10.5.10

Regular reflection of a shock waves in model tests with shadow method

Authors: S.I. Gerasimov1,A,B,C,D, A.V. Zubankov2,A,B, V.À. Kikeev3,C,D, Y.U. Smirnov4,A, N.À. Trepalov5,A, R.V. Gerasimova6,B

A Russian Federal Nuclear Center - The All-Russian Research Institute of Experimental Physics, Sarov, Russia

B Sarov Physics and Technical Institute of National Research Nuclear University «MEPHI», Russia

C Institute of Problems of Mechanical Engineering RAS, N.Novgorod, Russia

D Nizhny Novgorod State Technical University n.a. R.E. Alekseev, Russia

1 ORCID: 0000-0002-6850-0816, s.i.gerasimov@mail.ru

2 ORCID: 0000-0002-0515-2092

3 ORCID: 0000-0002-2375-0803

4 ORCID: 0000-0002-5419-5312

5 ORCID: 0000-0002-5131-1736

6 ORCID: 0000-0002-2711-3975

 

Abstract

The basic specific feature of the shadow method consists in absence optical components between an object under study and the registration plane. The object is illuminated with divergent (most often homosentric) or parallel beam. Distribution of the illumination in the pattern obtained is connected with change of the second derivative of the gas density with respect to directions, which are perpendicular to rays. The most part of information in experimental aerodynamics of compressible gas is obtained with the help of this simplest method. Heading for application of shadow method one should keep in mind that illumination distribution in the registration plane depends on the distance between the plane and the object under study. Strong refraction of light rays passing through the object may significantly distort geometrical projection of the object and more the object-screen distance the larger the distortion. The distortion lowers accuracy of measurements of geometrical coordinates, especially of angular ones. In the work the shadow method has been applied for study the regular and Mach reflection of a shock wave from pane and circle surfaces. Experimental data on reflection angle of bow shock have been obtained.

 

Keywords: Supersonic flow visualization, shadow method, regular and Mach reflection, incident and reflected shock waves.