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The article discusses the conditions for increasing the passive safety of vehicles due to the use of the results of calculating the temperature regime in frictional friction pairs in the design of brake assemblies, both taking into account their active heat dissipation, and taking into account the contact thermal resistances along the path of the dissipated heat flows. This temperature calculation allows, at the design stage of new brake units, to determine their optimal geometric arrangement, taking into account the increased thermal dynamics of friction of friction pairs during their active heat dissipation. In addition, it becomes possible to recommend the optimal frictional pairs of friction in the brake units, taking into account their thermal stability. The use of the above thermal calculations will ensure an increase in the performance of the brake units, which, ultimately, will provide an increase in the passive safety of vehicles.

A source or drain of any shape, whether moving or stationary, acting temporarily or permanently, may be represented as a system of point instantaneous heat sinks (drains). This provision is called the principle of designing solutions. The process of heat propagation in a body of limited size can be represented as the process of heat propagation in an unlimited body, if the actual sources are supplemented by some system of dummy sources or heat sinks. The algorithm developed is as follows. The forces acting on turning on the front and back surfaces of the cutter are calculated. At external longitudinal turning of structural steel, tangential Pz and radial Py are the components of the cutting force. Calculate the dimensions of a flat source of heat on the front surface of the cutter, the flat area of the contact of the chips with the front surface. Calculate the temperature at the tip of the cutter with constant heat exchange. As a result of the research, the substantiation of the concept of mathematical model for use in the execution of turning works is offered, where the choice of such cutting modes is important so that, with the known characteristics of the material being processed, the temperature of the cutter does not exceed the maximum possible. This in turn provides effective planning and cost-effectiveness of the cutter. All this allows you to adjust the modes and costs in the work developed a calculation algorithm for the given processing conditions - properties of the machined and tool materials, geometric parameters of the tool and cutting modes to determine the temperature at the top of the lathe using the source method. The scientific novelty is to use the known method of heat sources for the calculation of a specific technical problem: the calculation of the temperature of the tip of the cutter when processing a specific part The practical importance of the work lies in the possibility of using the developed algorithm in practice in the manufacture of specific parts, because it is known that exceeding a certain temperature of the cutter can lead to sad results. The work can also be used in the educational process for students studying heat engineering.

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Performed research work to determine the effect on the fuel cells of the temperature and change the shape of the elements (plates) in contact with hydrogen. It has been confirmed that the plate change takes two stages. In the first short time step, the maximum form of plate change is achieved. The temperature-dependence of the maximum bending of the plate obeys the extreme law. In the second, substantially longer phase, the plate is straightened. At low temperatures, the residual stationary bending of the plate is 20-30% of the maximum bending value. With increasing temperature, the bending rate of the plate increases and at 320-350oS the phenomenon becomes completely reversible. The mechanism of changing fuel cell form is discussed. As a result of the study, the experimental regularities of the hydrogen-induced form of change of the palladium plate are established, it is determined that a temporary "metal-hydrogen" gradient material is formed at hydrogen saturation and hydrogen concentration stresses always arise. This, in turn, provides for efficient planning and determination of the time of penetration of hydrogen into the metal, controlling the shape change, and allowing the fuel cell to operate. It is determined that the maximum bending of the plate with increasing temperature changes according to the extreme law and in the temperature range 220-260oS the bending reaches the maximum value. It is shown that the maximum bending of the plate is determined by two fundamental properties of the Pd-H system, namely, the diffusion coefficient and the equilibrium solubility of hydrogen in palladium. The scientific novelty is the use of the known material palladium, which in contact with hydrogen becomes a temporary gradient alloy with variable physical properties. It is established that the heat exchange in the plate and the energy equilibrium around the plate are based on the velocity on the heat flux that occurs during reactions in the fuel cells and the heat losses that occur in the fuel cell. The practical importance of the work lies in the possibility of using the developed algorithm in practice in the manufacture of specific devices operating on the basis of a fuel cell - hydrogen, with the possibility of modeling this process in Matlab. But improving the working conditions of fuel cells and hydrogen sensors, because at low temperatures there is a relatively small residual bending of the plate, and accordingly the shape of the fuel cell.