FOREWORD

The present issue of the Journal of Engineering Physics 
and Thermophysics (Inzhenerno-Fizicheskii Zhurnal) contains the main 
results of research carried out in 1997-1999 by a team of staff members 
(about 30 in number) of the Academic Scientific Complex "A. V. Luikov 
Heat and Mass Transfer Institute" of the National Academy of Sciences 
of Belarus, Belarusian State University, and Moscow Engineering Physics 
Institute within the framework of the project of the International 
Science and Technology Center (ISTC) "Mathematical Simulation of Natural 
and Human Activity Accidents and Their Influence on Environmental 
Conditions and Ecology" (project B23-96).

Large-scale catastrophes caused by the fall of large extraterrestrial 
bodies, volcanic eruptions, inadvertent explosions of ammunition warehouses, 
accidents at petroleum storage depots, oil and gas pipelines, and 
nuclear power stations, etc. have a number of common characteristic 
features. To a certain extent they represent a combination of such 
physical processes as intensive flow of compressible and incompressible 
media, molecular, convective, and radiative heat exchange, plastic 
flow and breakup of the condensed phase of matter, melting, evaporation, 
and condensation, ejection of large quantities of matter and heat 
into the atmosphere; complex chemical transformations of initial products, 
etc. Frequently the consequences of such events exert a substantial 
effect on the ecological situation and the environment. Existing methods 
of mathematical simulation and ones being developed allow prediction 
of the dynamics of these complex processes and the ensuing consequences 
in various time, space, and energy scales. Therefore, it is difficult 
to overestimate the immediate importance of this approach.

The objective of the project was to develop a unified approach 
to the solution of a wide range of large-scale energy catastrophes 
by the methods of mathematical simulation. For this purpose new physical-
mathematical models of the phenomena that accompany large explosive- 
and impact-type energy catastrophes were improved and developed, new 
physical-mathematical models of the properties of matter at high 
energy densities were developed, the numerical algorithms for their 
realization were constructed, software was created, and numerical 
experiments on simulation of the above phenomena were performed.

The problems considered in the papers presented in what 
follows cover a wide range of kinetic, gas-dynamic, hydrodynamic, 
and thermophysical phenomena that accompany the entry of large meteoroids 
into the earth's atmosphere (hypersonic flow and thermal destruction 
of bodies, radiation of gas heated in shock waves, chemical reactions 
in air and vapors, etc.), impact on solid and water surfaces, formation 
of craters, tsunami, etc., and the processes of volcanic eruption 
and evolution in the atmosphere of the products of volcanic ejection 
of explosive and jet type. Study of the above-indicated processes 
is impossible without the creation of appropriate databanks on the 
optical-physical characteristics of heated gases and plasmas 
and condensed media in the range of high temperatures and pressures.

In our opinion, these articles can be of interest to a 
wide range of specialists who work in the field of studying fundamental 
problems of high-temperature thermophysics, radiative plasmodynamics, 
and the behavior of matter at high energy densities.

The papers presented can be grouped into the following categories:

1. Properties of media (equations of state, optical characteristics), 
problems of transfer of radiation and matter.

2. Hypersonic flow, high-velocity impact, and the consequences 
caused by these processes.

3. Mathematical simulation of water waves caused by high-power 
external perturbations.

4. Simulation of processes in the atmosphere caused by 
high-power volcanic ejections.

It should be noted that a number of results obtained in 
the course of carrying out the project were published in other issues 
of the Journal of Engineering Physics and Thermophysics and other 
publications. Detailed information about these articles can be found 
on the Internet (http://www.itmo.by/division/rgd/ists-b23-96.html).

We realize that the announced claims exceed the factual 
material contained in the works presented. Therefore we are ready 
to acept with gratitude any comments. At the same time, we hope that 
the readers' criticism will give us the impetus to do something better 
or something differently. We will believe that the primary purpose 
has been achieved in that case.

For a long time the authors of the papers published below 
have worked to obtain the end result. The possibility of being involved 
in solving problems that are far from applied ones has appeared almost 
for the first time. In these works we actually tried to follow the 
spirit of conversion in essence, and therefore our approaches can 
appear unusual in some way to those experts whose fields we have
unintentionally intruded upon.

The project has given us the possibility of perceiving 
ourselves in a different quality, making no claims to specialized 
knowledge in areas new to us. We recognize the insufficiency of our 
experience. This is only the beginning. We wish to develop the possibility 
presented to us and to obtain more significant scientific results. 
An important point is that we wish to improve what we have achieved. 
We believe that the ISTC has given impetus to our work and has opened 
for us the possibility of participating in international cooperation.

In this connection we are deeply grateful to the administration 
and staff of the International Science and Technology Center, whose 
kind attitude and support were felt by us throughout our work.

G. S. Romanov, Scientific Head of the Project
N. V. Pavlyukevich, Scientific Adviser to the Project