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To deepen the cracking of crude and heavy petroleum products, they are heated in tube furnaces, and the decomposition products are subsequently held in an external reaction chamber [1,2]. Disadvantages of tube furnaces result from combined heating and thermal decomposition of the petroleum products (this eliminates their mutual regulation, and optimization), as well as vigorous carbon deposition on the walls of the tubes. Additional holding of high-temperature decomposition products exiting from the furnace in an external reaction chamber does not ensure their complete thermal decomposition as a result of secondary reactions.Let us examine the possibility of deepening the cracking of petroleum products and destructive processing of polymeric wastes by organizing those conditions for which the heating and thermal decomposition of the products are separated in time and space, while heating of the liquid products will ensure attainment of the boundary of the phase state by the most thermally stable components. At this boundary, all nonvolatile fractions go over into the gaseous phase, and cooling occurs due to absorption of the heat liberated by the decomposition reaction. This process takes place as a result of heating of the reaction mixture at a temperature and pressure, which are sufficient to throttle the evaporation processes and the reaction in the tube furnace, and which are required to convert the mixture to a state of attainable superheat of the most thermally stable components in the reaction chamber. For this purpose, the pressure at the end of the coil should exceed the pressure in the chamber. Provision for attainable superheat of nonvolatile components that proceed into the chamber is a requisite condition in selecting the pressure differential and the temperature of the reaction in the coil and chamber. A pressure increase in the coil will lead to an increase in the temperature of the mixture, and to a reduction in the content of gaseous phase, which prevents rapid heating of the mixture in the coil, as a result of which the thermal flux through the wall of the coil and the amount of heat accumulated in the products being heated will increase, and, accordingly, coke formation will decrease. The thermal-decomposition reaction takes place as a result of a pressure drop when the mixture enters the reaction chamber, whereupon the increased reserve of thermal energy intensifies thermal decomposition of the mixture in the chamber, and ensures increased output of volatile fractions.It is known that the rates of the decomposition reaction are lower in the liquid phase than in the gaseous phase owing to the so-called cage effect. As the molecules dissociate, a pair of radicals that has been formed in the liquid phase, exists for a certain time (10 -9 -10 -10 sec) in a single cage; intracage recombination, and equilibrium shift in the direction of the initial compound are therefore possible. If the mixture goes over into a state of attainable superheat as a result of a pressure drop, the components of the mixt...

It is known that relative elongation ~. can be used as one measure of the uniaxial deformation of polymeric structures, especially in regard to cross-linked polymers [ 1 ]. However, it can be concluded from the available empirical data that this measure satisfactorily describes the behavior of a polymer only if ~. < 2-3. For several reasons, relative elongation cannot be used if the deformation of the polymer is substantial [2]. One of these reasons, in our opinion (particularly for polymers having globular structures) is the formation of knots in the molecular filaments that comprise a molecular unit (globule).In connection with this, it is interesting to attempt to determine the dependence of the deformation measure on the presence of knots in a globule in the form of a function of ~..We make the following assumptions: 9 for the duration of the stretching process, the globule is a sphere with the initial radius R 0 and the running radius R;9 the process of deformation of the globule entails pulling from it a perfectly inextensible filament having the radius r;9 as a first approximation, we ignore the theological properties of the material undergoing deformation; 9 we assume that the coefficient of friction f between the molecular filaments of the globule is constant and is independent of the forces and the speeds at which the filaments slide relative to one another; 9 we assume that the knots are uniformly distributed in the globule and are separated the distance l 0 from one another along a molecular filament; also, during uniaxial deformation, the knots are gathered together into the form of a loop at the exit from the globule.Knowing that the force P0 with which the first knot (loop) is stretched into a filament exiting the globule depends on the theological and other parameters (which are not examined in this article), we use Euler's formula [3] to calculate the tensile force on the nth knot:where ~p = 2~zn is the inclusion angle of the filament being stretched; n is the number of knots (loops).The total pulling force F will obviously be represented by the sum of the frictional forces from each of these knots: n F=fPnfdn. 0We find the relationship between the number of knots n and the measure of deformation ~, in accordance with the scheme depicted in Fig. 1. The difference between the initial and current volumes of the globule can be considered to be roughly equal to the volume of a molecular filament pulled from the globule:1 Russian College of Chemical Engineering. 2 MGUII~.

Представлен алгоритм расчета оптимальной толщины преграды, преодолеваемой сфериче-ским телом с заданными геометрическими, кинематическими и физико-механическими пара-метрами. Алгоритм основан на анализе деформации преграды и сферического тела. В методи-ке расчета используется минимум параметров тела и преграды, представленных в соответ-ствующих справочных материалах. Методика не требует дорогостоящих механических и бал-листических испытаний, основана на расчете баланса энергий: энергии деформирования пре-грады и сферического тела, энергии по перемещению тела вплоть до возникновения предель-ных напряжений, приводящих к разрушению преграды, и первоначальной кинетической энер-гии сферического тела. Приведен пример использования методики (алгоритма) расчета, кото-рый показал достаточно точное совпадение экспериментальных и теоретических данных.Ключевые слова: тонкостенная пластическая преграда, сферическое тело, кинетическая энергия, энергия деформации, пластический модуль, оптимальная толщина преграды, мето-дика определения толщины. ВведениеОпределение оптимальной толщины оболочки, пробиваемой перемещающимся телом (снарядом), всегда было актуальной задачей в разных отраслях промышленности, особенно в военной, при проектировании защитных кожухов, переносных щитов, заборов и т. д. Именно поэтому задача создания и совершенствования методики расчета и оценки пробиваемости пла-стической преграды летящим сферическим телом, несомненно, актуальна.Существующие методы расчета толщины преграды, преодолеваемой сферическим те-лом, как правило, имеют эмпирический характер, т. е. требуют проведения дорогостоящего экс-перимента (испытания), который не всегда можно реализовать. В частности, в работах [1, 2] приведены графики баллистических испытаний с эмпирическими формулами, на основании ко-торых определяется толщина пробиваемой преграды. Для расчета толщины преграды из другого материала требуется проведение аналогичного дорогостоящего испытания.Целью нашего исследования являлась разработка методики расчета толщины тонко-стенной пластической преграды, преодолеваемой сферическим телом, при минимуме физико-механических и кинематических параметров материалов преграды и тела. Алгоритм расчета толщины преграды, преодолеваемой движущимся теломРассмотрим шарообразный снаряд радиусом R, м; плотностью ρ, кг/м 3 ; движущийся с первоначальной скоростью v, м/с. Характеристики материала снаряда: условный предел те-кучести -σ 02с , Па; предел прочности -σ В с, Па; относительное сужение при разрыве -ψ с.Преграда -первоначальная толщина S, м. Характеристики материала: предел прочно-сти σ В п, Па; условный предел текучести σ 02п, Па; относительное сужение при разрыве -Ψ п .Допущения: -пренебрегаем упругими свойствами снаряда и преграды; -вся кинетическая энергия снаряда переходит в работу по перемещению снаряда и по деформации преграды и снаряда; ISSN 2072-9502. Âåñòíèê ÀÃÒÓ. Ñåð.: Óïðàâëåíèå, âû÷èñëèòåëüíàÿ òåõíèêà è èíôîðìàòèêà. 2017. ¹ 1 8 -пренебрегаем краевыми эффектами на периферии преграды (ее площадь покрывает зо-ну пластической деформац...