Досліджуються особливості продукування теплоти в процесі згоряння пальної суміші в циліндрі двигуна внутрішнього згоряння. Як з'ясувалось, типовим для робочих процесів в отто-двигуні внутрішнього згоряння є те, що до миті досягнення максимальної інтенсивності теплотворення загальна кількість виділеного тепла складає 49 % від потенційно можливої-тієї, яку приховує в собі пальне, що потрапило в робочий простір двигуна. На різних режимах роботи двигуна параметр m , що характеризує сукупно максимум інтенсивності теплотворення і мить його настання, набуває значень, близьких до
Theoretical background. A number of researches claim that the classical theory of dynamic systems ignores spe-cial cases of incomplete equivalence of mathematic transformations descriptions. Sometimes it is even argued that (con-trary to a prevailing paradigm) the study of purely discriminatory polynomial of control system (the system of differen-tial equations) fails to guarantee the correct judgments about the parametrical stability and system’s stability factors as the probably wrong interpretation of stability may result in accidents and even catastrophes caused by a defectively designed object. Such conclusion obviously ensues from the fact that there are examples of the systems that have the same discriminatory polynomial but differ substantially in the parametrical stability and stability factors under the vari-Bulletin of Lviv State University of Li fe Safety, №19, 2019 35 able parameters. These researches are concerned about the fact that generally used packages of applied programs – for they usually require the equivalent in the classical sense consolidation of differential equations system to a single “standard” form – are not able to secure the veracity of dynamic systems computation and to guarantee the correctness of their characteristics analysis without the application of additional controlling subprograms. For example, there may exist the risks of stability losses in the initial system, however being brought to the differential equations of first order, as a common practice, these risk will become absolutely imperceptible, and, as a result, the source of dangerous casual-ties may occur – accidents and catastrophes in case of the system material embodiment. Thus it is categorically declared the necessity of substantial researches in correctness of the results of engineers and IT specialists and of relevant amendments of bachelors and masters degrees curriculum. The purpose of the research. Thus, it is natural that there is a necessity to find out whether the previously imper-ceptible risks of accidents and catastrophes do exist and whether the classical dynamic systems theory does not take into consideration the unexpected possibilities of its problems correctness losses as a result (in the process) of their equiva-lent transformations. The aim of this article is to substantiate the essence and content of this kind “discoveries”. The paper provides a comprehensive analysis of the system’s simple examples that are to prove the possible risks from the equivalent, in classical sense, transformations of mathematical descriptions.Results and discussion. It has been found out that after the equivalent transformations instability as well as incor-rectness in fact do not “hide”, they do not become invisible and untraceable. The researchers rather consciously do not pay attention to the possible substantial deformations of the system. For indeed, in case of the reduction of the system description to the form of the normal system of differential equations of first order the possibilities of the stability loss become invisible not because the transformations were nonequivalent but because the variability of the system order is not prognosticated, and, therefore, the treatments of initial (where the change of order is obvious) and final systems differ considerably. Here at, the controller equation — the defined first integral — is the manifestation of one more possible system order which cannot be ignored. Actually, much depends on how we define, see, read, interpret the ana-lytical description of a certain phenomenon or process. Different characteristic determinants that identify, materially, different dynamic systems may correspond to the same characteristic polynomial. The determinant may be consciously equivalently transformed (deformed), and any transformed (deformed) determinant will identify a new system. Thus, any transformation – is, without exaggeration, the creation of something new, something different. The process of solving simple linear differential equations with fixed factor and their variation with the aim of so-lutions stability or analytical descriptions correctness evaluation is reduced to the solution of a relevant algebraic prob-lem and the research of its properties and characteristics. Consequently, there is no point in expecting any enigmatic or dramatic unexpectancies when the research is sophisticated and profound. Conclusions. The characteristic determinant reflects the properties of any system more deeply than the character-istic polynomial does. Any equivalent transformations of the system are always visible in the structure of the determi-nant, even if they are not defined in its equation roots (zeroes). In the result of equivalent transformations there certainly emerges a new formation – it looks like the same system but with new properties (otherwise there will be no necessity in any transformations). The loss of robustness is treated as an unexpectancy occurring as a result of motivated defor-mation of the system which is easy prognosticated. Nonrobust systems could have their own perspective. Their exten-sive application is advancing.
The general principles and strategies to control the work of switching devices in a step transmission of the car are considered. It is assumed that the synchronization of the rotation of the transmission elements during the change of gears is carried out with the active participation of the engine, without interrupting the flow of energy to the wheel engines and with accurate reproduction of an arbitrary program of car movement. For clarity, the study of control algorithms of the "engine - transmission" system is based on the analysis of the effectiveness of possible modes of clutches operation. However, in reality, it is a completely abstract process and it does not make sense to associate it with a specific technical embodiment. The measure of process efficiency is governed by energy consumption. It is taken into account that: 1) the process of shifting determines the modes of engine operation which is actively involved in the implementation of the shift, and this affects fuel consumption; 2) gear shifting and concomitant synchronization of rotational movements are always associated with the dissipation of energy in the form of heat.It was found that it is possible to objectively assess the effectiveness of the control of gear shifting processes if we consider them through the prism of optimal control of the overall system "engine - transmission". But it is easy to understand that the Zeroshift concept is by all indications the embodiment of a kind of "technical" compromise as opposed to various formal compromises. In this case, the process of actual gear change is reduced to almost an instantaneous act of gear change, which will significantly affect the principles of the general theory of "engine - transmission" system optimal control: the synthesis of control laws will be reduced to the construction of shift maps, but this will exacerbate the problem of so-called looping.
The laws of gear transmission are practically always transformed into rather illustrative and relatively easy programmed in the controller the so called maps of transmission. But the notion of optimality are prone to misunderstanding. To avoid this it is suggested a driver opt for himself for the factored technical possibilities of multiprogrammed automated or automatic control of transmission, or at sole discretion to implement a certain programing compromise that in most cases is not disclosed. Thus the system of automated control is subject to uncertainty. There has been no theory able to recommend an irrefutable compromise. It turned out that alongside with insufficiently optimal laws of gear transmission the so called cycle of shift operation occurs, i.e. excessive or irrational changeability of structure and parameters of transmission which cannot be blocked by the criterion of optimality. To contend this phenomenon the optimal laws are considerably distorted and invalidated. So, why do we strive for optimality? Was it really necessary to create a true model of automobile, search for the sense of ultimate transmission? Are there any other issues possible more important than dynamics, energy saving, purely technical factors that determine the efficiency of transmission? Should we prognosticate artificially created chaos in the control system while programming asystemic errors in the operation of the controller? It is obvious that these questions presuppose substantial negative answers that are to be proved. However, there are grounds to suggest completely different explanation of gear shift optimality laws: when a driver chosen program of automobile motion is realized we can mention only the energy saving, whereas the requirement of dynamics means “interference” in driver’s actions, “limitation’ of the freedom of choice, decrease in operability within the “drive – automobile” system. This treatment of the sense of transmission automation is firmly grounded. “Dynamics” is based only on the assumption that there exists an indicator of car sensitivity to the driver. If both paradigms coexist, undoubtedly, everything related to one of them is absolutely false. It is the traditional paradigm that seems false, for it relies on so called map of shifts. Due to this fact in the theory of automated operation of “engine – transmission – automobile” system there has long been ambiguity in the understanding of automobile transmission operation. And this statement is the fundamental, key one in defining really objective principles for the synthesis of automobile transmission operation laws. The aim of this paper is to reveal the content, evaluate the objectivity and credibly validate both paradigms contesting in the theory of automobile stepped ration gear transmission and constituting the basis of synthesis theory of optimal gear shift laws in these transmissions. Usually, the problem of gear shift softness is treated outside the general motivation of the gear shift optimization laws. It is considered that the softness of the shift is just a reason of comfort and prevention from harmful dynamic load of transmission. In fact the synchronization of transmission elements rotation under participation of engine is directly connected with transference of energy to automobile’s propulsion units and the accuracy of the desired motion program representation. That is why the effectiveness of synchronization is to be evaluated according to the same criteria as the rationality of the choice of transmissions. It is worth mentioning that in the process of active (with the participation of the engine) operation of synchronization the automobile transmission transforms to the variator that, although it dispels energy in the form of the heat, potentially allows the engine to work longer and under more energy saving modes. It is proved that the optimization of the gear shift laws should be considered solely according to the criterion of energy saving. Herewith, the organization of the process of shift from one transmission to another should be submitted solely to the laws of energy saving rather than to the requirements of softness that could hardly be formalized. In this case the algorithms of internal combustion engine operation in the process of automobile transmission shift (in the process of clutches slipping) are of great importance.
Annotation. The general methodology of parametric optimization of systems is considered for two arbitrary cri-teria simultaneously. The so-called principle of expanding an optimization problem is proposed, which creates the basis for finding guaranteed unambiguous solutions, without resorting to artificial formal means of «collapse» of the two cri-teria into one. It turns out that a very common multiplicative criterion for so-called fair trade-off actually expresses the average geometric basic criteria. It is easy to reduce (lead down) it to additive. Therefore, it is certainly not known, why he should give preference to the arithmetic mean (after the appropriate coordinate) of the dimensions of the primary criteria. There are more subjective and far-fetched than objective and truthful in the criterion of a fair compromise.Perfection is a permanent process — it has a beginning but has no end. In that the new" perfections arise from time to time and each of them definitely use a certain time, then, of course, the process of perfection is a step-by-step process, an endless step to an unattainable ideal. This particular circumstance should be taken into account.Described algorithms for optimal search formally reproduce on a primitive model plane the real process of step-by-step improvement of all man-made - from acceptable to better... There are no examples when something was created immediately unconditionally optimally (and the ideal — at all not recognizable and therefore not embodied). At each step, one of the algorithms regulates minimizing the value of a single criterion, without affecting it, without changing the other. That is why there are no conflicts outside the attractor. Only within the attractor, for which the line (which is a one-dimensional attractor) rules on the model plane, the consistency disappears. Another algorithm combines a series of steps in each of which only one parameter varies, and the gain at the same time has both supporters of one perfection, and supporters of some other perfection. Consequently, there are no conflicts, until the algorithm does not attract the attractor, which this time is an area on a model plane, that is a two-dimensional attractor.Within the attractor, all solutions to the optimization problem is appropriate without a doubt, even advisable to consider completely equivalent. However, in fact, insurmountable subjectivism does not allow us to adhere to this idea (let's say, without the participation of any dictator).
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