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Maintaining optimal parameters of the microclimate in the car along the route is the most important requirement for the passenger’s travel. In the 1st class passenger cars, maintaining optimal microclimate parameters is achieved through the operation of the air conditioning system, which provides individual regulation of the air temperature in each compartment. Individual air temperature control systems used in air conditioning systems are divided into two groups: active and passive.The article proposes for consideration a combined active-passive system with a separate air supply with a lower and higher temperature compared to the temperature maintained in the compartment and the installation of individual induction terminals, which makes it possible to increase the efficiency of individual regulation of air parameters in the compartment.To assess the uniformity of temperature distribution and air flow rate over the car volume with the proposed control scheme, a three-dimensional modeling of the distribution of these parameters in the compartment was carried out on the basis of Autodesk CFD software.The given simulation results indicate the uniformity of temperature and air flow rate distribution over the compartment volume, which makes it possible to characterize the proposed system as sufficiently energy efficient, easy to operate and reliable in operation.

The article shows the structure of the computer program “Express estimation system of the heat transfer coefficient for the vehicle”. The performance sequence of the automated calculation for determining the heat transfer coefficient ( K ) is described on the example of the refrigerator car body with the use of the data obtained during the accelerated thermal engineering tests. The advantages of the announced program are shown, consisting in a substantial reduction in the duration of testing, excluding the influence of the human factor when performing calculations and reducing the costs of organizing documentation flow. It was noted that for the operators of isothermal vehicles (ITV) the formation of an automated database with the calculated values results of K allows not only to monitor the dynamics of their changes during the ITV operations, but also with sufficient accuracy to predict the time of reaching the critical values of K , after which the regular energy installations will work with a significant expenditure of fuel and energy resources. The results of the expected economic efficiency in determining K by the accelerated method are presented; its value for the main types of ITV operating in the JSC “RZD” will be at least 14.0 billion rubles.

We study the kinetics of the photovoltage decay in silicon crystals, caused by the effect of lowenergy (E = 8 keV) X-ray radiation. A correlation between radiation-induced changes in the short-term and long-term components of the photovoltage decay and the charge state of the surface, determined by measuring the surface distribution of the amplitude and decay time of the photovoltage, is found.

The effect of a weak permanent magnetic field on the structure and charge state of silicon for solar-power engineering is investigated. It is revealed that magnetostimulated changes in the defect-impurity state and surface potential have a reversible character.