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11 
A new Continuous Hugoniot Method for the numerical study of shock wavesLane, James Matthew Doyle, January 1900 (has links) (PDF)
Thesis (Ph. D.)University of Texas at Austin, 2005. / Vita. Includes bibliographical references.

12 
The production of hypersonic shock waves in an electrothermal diaphragm shock tubePhillips, Malvern Gordon Rutherford January 1969 (has links)
The operation of a diaphragm shock tube of 5 cm inside diameter in which the driver gas is heated by the discharge of electrical energy ( ~ 10³ joules) is analyzed in detail. A technique is described for the measurement of the heated driver gas pressure and empirical relations are obtained which enable the shock speed to be calculated from a knowledge of the discharge
voltage and test gas pressure. Using helium driver gas initially at atmospheric pressure, shock Mach numbers of about 20 are obtained in argon at an initial pressure of about 1 Torr. The separation of shock front and contact surface is analyzed by means of a convenient shock reflection technique using a smear camera. The properties of the shockheated gas are shown to agree with the predictions of standard shock wave
theory, which yields a temperature of about 1.3•10⁴°K and an
electron density of about I0¹⁷ cm⁻³ for the case of a Mach 20 shock in argon at 0.5 Torr. In this case the shockheated gas sample is observed to be about 5 cm in length at a position 1.2 meters from the diaphragm. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

13 
Stability of converging shock waveFong, Kenneth SauKin January 1978 (has links)
The stability of converging waves was analysed with theory and by experiment. A computer code was written in
FORTRAN language for the calculation of wavefront positions of plane shock waves and cylindrical converging shock waves in ideal gas. The criteria for stability were defined and the
limit of stability of imploding shock waves was obtained using the code. In order to test the model, an experiment was
set up to generate shock waves in an electrothermal shock tube. These shock waves were made to propagate into a
wedged channel, and the variations of the shapes of the waves front were measured from high speed framing camera pictures. Good agreement was found between the experimentally observed velocity and the model calculation, indicating that the computer procedure is a valid method to analyse the stability of converging waves. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

14 
Bleed effects on a conveying cylindrical shock waveYu, Thomas Sathong. January 1977 (has links)
No description available.

15 
A theoretical investigation of the propagation of shocks and imploding blast waves in a decreasing density field.Habashi, W. G. January 1969 (has links)
No description available.

16 
Transmitting boundary in dynamic computationShen, Feng Qiang January 1988 (has links)
No description available.

17 
An investigation of high speed metal forming with liquid shock waves.Kosing, Oliver E January 1998 (has links)
A thesis submitted to the Faculty of Engineering, University of the Witwatersrand,
Johanneaburg, in fulfilment of the requirerments for the degree of Doctor of Philosophy. / In this work a new high speed metal forming process is experimentally and theoretically
investigated and discussed. The high speed metal forming is carried out in a
liquid shock tube. The pressure energy of a liquid shock wave, which is generated
nonexplosively is used to form the metal workpiece.(abbreviation abstract) / Andrew Chakane 2019

18 
Eﬀect of internal surface curvature on steady axisymmetric shock wavesFilippi, Alessandro Antonio January 2017 (has links)
A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulﬁlment of the requirements for the degree of Master of Science in Engineering, 2017. / The cardinal aspects of supersonic and hypersonic propulsion intake design involve understanding the internal shock wave structures forming therein. A study was conducted to explore the eﬀects of internal surface curvature and entry deﬂection angle on steady axisymmetric shock waves. Very little is known about these inﬂuences with only Curved Shock Theory, produced by M¨ older, providing analytical insight directly after a curved shock wave.
The shock waves and accompanying ﬂow ﬁelds which were generated were studied via experimental and numerical means. Radius normalised internal radii of curvature of 1, 1.5 and 2 with entry deﬂection angles of 0◦, 4◦ and 8◦ were investigated between a Mach number range of Mach 2.4 and 3.6. Experimental results were produced using a blow down supersonic wind tunnel facility and were captured via shadowgraph and schlieren ﬂow visualisation techniques. The numerical simulations were validated using the experimental results.
A self similar curved shock wave shape equation was presented with an empirical model which uses ﬂow Mach number and internal radius of curvature in order to produce the resulting curved shock shape. Curved Shock Theory streamlines were used to try predict the internal surfaces that produced the curved shocks but results did not correlate. This was due to extreme streamline curvature curving the streamlines when the shock angle approached the Mach angle. Very good agreement was however found between the theoretical and numerical streamlines at lower curvatures. The higher the internal surface curvature and entry deﬂection angle, the greater the ﬂow ﬁelds were impacted. Steeper characteristics formed as a result, curving the shock wave more noticeably. Both the internal surface curvature and entry deﬂection angle were found to have an eﬀect on the trailing edge expansion fans which then altered the shape of downstream shock wave structures. The highest curvature models produced steady double reﬂection patterns due the ﬂow being turned in onto itself by the imposed internal surface curvature. The eﬀects of conical and curved internal surfaces were explored for additional insight into the presence of ﬂownormal curvature and the curving of the attached shock waves. / XL2018

19 
The eﬀect of wall thermal conductivity on shock wave reﬂectionBerry, Richard January 2017 (has links)
A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulﬁlment of the requirements for the degree of Master of Science in Engineering, 2017. / In traditional twodimensional shock wave theory the reﬂection of a shock wave oﬀ a surface is treated as an adiabatic process and that the reﬂection surface is perfectly rigid and smooth with an inviscid ﬂow of the ﬂuid. In reality it has been found that these assumptions are not entirely accurate, and that although they are a good indication in the regular and irregular reﬂection domains of shock waves over the surface, viscous and thermal eﬀects are present within the ﬂow ﬁeld. It has been experimentally shown that the transition of regular reﬂection to irregular reﬂection exceeds the theoretical limit, which is known as the von Neumann paradox. This paradox has largely been accounted for in the formation of a viscous boundary layer behind the reﬂected shock wave, based on numerous experimental and computational studies. However, the thermal eﬀects in the reﬂection process have largely been neglected as the assumption of heat transfer between the postshock wave gas and the reﬂection surfaces is assumed to be invalid. These thermal eﬀects were investigated by testing materials with a varying range of thermal conductivities (1.13 to 401 W/mK) and similar surface roughness’s below the suggested limit for hydraulic smoothness. Each experiment placed two test pieces at the same incidence angle, symmetrically in the shock tube. This allowed ﬂow properties to be exactly the same for the two materials being tested with a single plane shock wave. Test Mach numbers ranged from 1.2790 to 1.3986, with tests conducted at shock wave incidence angles of 36◦, 40◦, 60◦ and 70◦. This allowed both the regular and irregular reﬂection domains to be tested. Shadowgraph images were created using a zconﬁguration optical set up. These shadowgraph images were analysed quantitatively based on the angles measured as well as qualitatively based on ﬂow features and symmetry. Both the quantitative and qualitative tests indicated that there was a diﬀerence in the angles between the reﬂected shock waves and surfaces based on the material thermal conductivity. In the quantitative tests the value of this angle was larger for materials with a lower thermal conductivity, and smaller for ones with a higher thermal conductivity for the regular reﬂection cases. In the irregular reﬂection cases the angle between the reﬂected and incident shock waves was larger for materials with a higher thermal conductivity. The materials with midrange thermal conductivities had reﬂection angles that lay within the bounds of the glass and copper angle values. The qualitative images supported these ﬁndings showing asymmetry in materials with diﬀerent thermal conductivities with the intersection of reﬂected shock waves lying closer to the material with a higher thermal conductivity. Control experiments using test pieces made from an identical material showed no bias due to the location of the test piece in the shock tube / XL2018

20 
Viscous Triple Shock Reflections Relevant to Detonation Waves, and Detonation Dynamics Predicted by the Fickett ModelLauChapdelaine, Sébastien SheMing 21 August 2019 (has links)
Two aspects of detonation dynamics are addressed in this thesis by articles. The first part of the thesis investigates shock reflection phenomena believed to be responsible for enhancing reaction rates in detonations, namely KelvinHelmholtz instability and Mach stem bifurcation caused by forward jetting. Three papers are presented.
The first numerically investigates shock reflections from a wedge under detonationlike conditions. A state of the art solver of the Euler equations is used. The shock reflection configuration is shown to depend on solver type, wedge implementation, and resolution. The type of reflection (i.e. regular or irregular) is found to depend on corner geometry, even far from the corner, showing initial conditions can play important roles in shock reflections.
These complications are addressed with shockresolved viscous simulations and a new initial condition: the triple point reflection. The numerical method is demonstrated in the second paper, and the presence of KelvinHelmholtz instability is investigated. Viscosity is found to play an important role in delaying the instability, which is found not to be a likely source of reaction acceleration on time scales commensurate with autoignition behind the Mach stem, but may become important on scales associated with the detonation cell.
Mach stem bifurcations are investigated experimentally and numerically in the third paper. Experimental shock reflections are performed from a freeslip boundary in gases with differing isentropic exponents. Bifurcations are found in experiments, viscous and inviscid simulations. Viscosity is found to delay bifurcations. Inviscid simulations are used to approximate the limits of Mach stem bifurcation in the phase space of Mach number, isentropic exponent, and reflection angle. A maximum isentropic exponent is found beyond which bifurcations do not occur, matching the irregular/regular boundary of the detonation cellular structure. Flow field instability is found in experiments at high Mach number and low isentropic exponent.
The second part of the thesis, comprised of one paper, investigates the dynamics of detonations with multiple thermicity peaks using Fickett's detonation analogue. Steady state analysis predicts multiple possible steady states, but only the fastest is singularityfree. Simulations show other solutions develop shock waves that eventually establish a detonation travelling at the fastest velocity allowed by the generalized ChapmanJouguet criterion. Characteristic and linear stability analysis shows these shocks are found to arise due to instability at the sonic points.

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