The reflexion and diffraction of shock waves

1964 ◽  
Vol 18 (4) ◽  
pp. 549-576 ◽  
Author(s):  
D. C. Pack
Keyword(s):  
Shock Waves ◽  
Recent Work ◽  
Experimental Techniques ◽  
Wide Field ◽  
Real Gas ◽  
The Past ◽  
Real Gas Effects ◽  
The Subject ◽  
Physical And Chemical ◽  
Theoretical Mechanics

When I was first asked to give a general lecture to the 5th British Theoretical Mechanics Colloquium (held at Liverpool University, 2–5 April 1963), I put up the title ‘Shock Waves’, thinking that I might run over a wide field of present-day research, pointing out some of the unanswered problems. In the intervening months, however, I came across the new book by Dr Bradley (1962) of Liverpool University,The Physics and Chemistry of Shock Waves, and as recently as last November there appeared a summarizing article by Pain bt Rogers (1962) of London University inReports on Progress in Physics. The first of these deals in great detail with the modern physical and chemical aspects of the subject—with real gas effects and experimental techniques-and the second summarizes the general classical properties and gives an extended account of recent work, for example, on real gas effects and on magnetohydrodynamics. I also bore in mind that magnetogasdynamics received a majestic treatment at the 4th Colloquium from Dr Shercliff. In the end, then, I decided to confine my remarks to one particular problem, namely the reflexion and diffraction of shock waves, and to concentrate mainly on developments during the past ten years. This paper is the text of the lecture.

General Characteristics of Hypersonic Flow Fields

1959 ◽  
Vol 63 (585) ◽  
pp. 503-508 ◽  
Author(s):  
R. N. Cox
Keyword(s):  
Boundary Layer ◽  
Supersonic Flow ◽  
Hypersonic Flow ◽  
Flow Fields ◽  
Real Gas ◽  
The Past ◽  
Boundary Layer Interaction ◽  
Real Gas Effects ◽  
The Subject ◽  
Interaction Problem

SummaryThe object of this paper is to give a brief account of the development of the study of hypersonic flow over the past three decades, and to stress some of the ways in which hypersonic flow differs from supersonic flow. In some of the early work on the subject a wrong emphasis was given to the study of flows with attached shock waves and to the nature of the shock boundary layer interaction problem, and it is only quite recently, mainly as a result of experimental work, that it has become possible to obtain a balanced picture of the important features of hypersonic flow fields. In the present paper real gas effects are not taken into account; in general, the inclusion of these effects will not markedly alter the picture given.

Shock dynamics of strong imploding cylindrical and spherical shock waves with real gas effects

2010 ◽  
Vol 22 (11) ◽  
pp. 116102 ◽  
Author(s):  
Malte Kjellander ◽  
Nils Tillmark ◽  
Nicholas Apazidis
Keyword(s):  
Shock Waves ◽  
Real Gas ◽  
Shock Dynamics ◽  
Real Gas Effects ◽  
Spherical Shock

scholarly journals Problematyka prawa do grobu w kontekście dóbr osobistych

2019 ◽  
pp. 19-33
Author(s):  
Anna Chodorowska ◽  
Łukasz Szumkowski
Keyword(s):  
Criminal Code ◽  
Civil Code ◽  
Wide Field ◽  
The Past ◽  
Personal Rights ◽  
Human Individual ◽  
The Subject ◽  
The Moment ◽  
The Right ◽  
Living Person

The historical feature of the protection of corpses, as well as the development of funerary tendencies, is an integral part of the functioning of our civilization, from the very beginning of time. The approach to death depends on the cultural and denominational circle as well as time. Respect for the living and the dead was in the past a separate division of civilization and thought development. Nowadays, new trends can be observed in the development of the protection of the human individual, as well as his name or reverence. In modern Polish legislation, the open catalog of personal rights (Article 23 of the Civil Code) is a wide field of interpretation in the very problem of the existence of specific goods. Undoubtedly from the provision of art. 23 k.c, it follows that this protection is due to the live unit, and thus only until its death. In modern Polish legislation, the open catalog of personal rights (Article 23 of the Civil Code) is a wide field of interpretation in the very problem of the existence of specific goods. Undoubtedly from the provision of art. 23 k.c, it follows that this protection is due to the live unit, and thus only until its death. At the moment when, according to the law, we cease to deal with a living person, and we start talking about corpses, certain rights are ceded to the closest persons, some are subject to inheritance. The right that people who are closest to someone’s death to cultivate this person according to their own conscience and religion and the contract between the entity authorized to burial and the cemetery management, as well as a number of related circumstances (on the drudge of several areas of law), will be called the right to the grave. The existence of the right to the grave belongs to arguable issues, as the liberty of the subject granting a certain sphere of possibility of proceedings, including its the scope of power. In the article, the Authors also discuss the issues related to the offense described in the art. 261 and 262 of the Polish Criminal Code. The dogmatic analysis carried out with regard to elements of a prohibited act has made it possible to establish, the scope of criminalization of these acts.

Algae in association with heterotrophic or holozoic organisms

1952 ◽  
Vol 139 (895) ◽  
pp. 185-192 ◽  
Keyword(s):  
Cell Wall ◽  
Recent Work ◽  
Marine Invertebrates ◽  
Algal Cell ◽  
Organic Food ◽  
The Past ◽  
Invertebrate Animal ◽  
Widespread Phenomenon ◽  
The Subject

The association of an alga capable of photosynthesis with another organism dependent on a supply of organic food, be it another alga, a fungus, or an invertebrate animal, is a very widespread phenomenon. The algae concerned are usually unicellular or simple filamentous forms, and, apart from the Zooxanthellae inhabiting marine invertebrates, are for the most part members of the Chlorophyceae or Myxophyceae. My theme is a very wide one, and it will therefore be necessary to confine my remarks to certain selected examples. The combination of alga and fungus to constitute a lichen has been the subject of repeated investigation and has been variously interpreted. Whilst in the past penetration of the algal cells, or gonidia as they are commonly called, by fungal haustoria had only been rarely reported and was regarded by many as something quite unusual, if not abnormal, the more recent work of Fry (1928), and especially that of Geitler (1933, 1934, 1937, 1938) and of his pupil Tschermak (1941, 1943), has shown that it is comparatively common. In some lichens the haustoria penetrate deeply into the algal cells, seemingly occupying an invagination of the protoplast, but not necessarily leading to its destruction. In heteromerous lichens it is more usual to find what have been called intramembranous haustoria which only penetrate through the cell wall up to the protoplast of the algal cell. Haustoria of this type are formed during the summer months and may be discoverable only for a comparatively brief period.

Real-gas effects in very weak shock waves in the atmosphere and the structure of sonic bangs

1971 ◽  
Vol 50 (1) ◽  
pp. 17-20 ◽  
Author(s):  
J. P. Hodgson ◽  
N. H. Johannesen
Keyword(s):  
Shock Waves ◽  
Thermodynamic Properties ◽  
Relaxation Times ◽  
Weak Shock ◽  
Approximate Expression ◽  
Humid Air ◽  
Real Gas ◽  
Real Gas Effects

An approximate expression is given for the thickness of weak fully dispersed shock waves. Using available data on the thermodynamic properties of air, it is shown that shocks of the strength expected in sonic bangs are fully dispersed. Estimated relaxation times for dry and humid air lead to wide variations in possible thickness, varying from millimetres to metres.

Studies of Parasite Oviposition Behaviour. I. Mastrus carpocapsae Cushman. (Hymenoptera: Ichneumonidae)

1956 ◽  
Vol 88 (2) ◽  
pp. 80-89 ◽  
Author(s):  
D. C. Lloyd
Keyword(s):  
Incomplete Data ◽  
Oviposition Behaviour ◽  
Field Conditions ◽  
Experimental Techniques ◽  
The Past ◽  
The Subject

The oviposition behaviour of numerous parasites toward hosts already parasitized has been the subject of a considerable number of investigations during the past twenty years. Many species of ichneumonids, braconids and chalcids have been shown generally to avoid oviposition in parasitized hosts under laboratory and field conditions but there are conflicting views on the nature of this behiviour and on the cause for such rejection (Salt 1935, 1937, Ullyett 1936). Incomplete data hearing on these problems with the parasite Mastrus carpocapsae are given here. Dificulties in laboratory propagation and particularly irregular and erratic oviposition under the experimental techniques employed have prevented a fuller study; hut it is felt that the data will be of interest to workers in this field of behaviour since in certain respects the findings help in the interpretation of relevant facts demonstrated in previous investigations.

Dusty Shock Waves - An Update

1996 ◽  
Vol 49 (10S) ◽  
pp. S141-S146 ◽  
Author(s):  
G. Ben-Dor
Keyword(s):  
Shock Wave ◽  
Shock Waves ◽  
State Of The Art ◽  
General Area ◽  
Gas Suspensions ◽  
The Past ◽  
Planar Shock ◽  
Dust Entrainment ◽  
The Subject ◽  
Dusty Shock Waves

A review of our original article [1] is given. It describes the state-of-the art of the subject of the propagation and attenuation of planar shock waves in dust-gas suspensions. In addition, it includes a brief description of the Dust Entrainment Phenomenon. This relatively new subject in the general area of Dusty Shock Wave has been getting more and more attention in the past few years.

Uneven Wear of Vehicle Tires

1993 ◽  
Vol 21 (4) ◽  
pp. 202-219 ◽  
Author(s):  
M. H. Walters
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Experimental Techniques ◽  
Lateral Stiffness ◽  
General Increase ◽  
Element Analysis ◽  
The Past ◽  
Uneven Wear

Abstract Advances in tire construction have led to major increases in tire life over the past twenty years, mainly by increasing the lateral stiffness and thus reducing slip during cornering. However, this general increase in tire life has tended to highlight the problem of uneven wear. In the present paper, three new experimental techniques are described which have been developed to study treadwear distributions. These techniques are evaluated and their results compared with a finite element analysis. Taken together, they indicate some of the causes of uneven wear and may be used to identify tire design and service features which contribute to uneven wear.

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