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Introduction. The tasks of increasing energy saving in heating systems for passenger cars of diesel trains are currently relevant. As an alternative source of energy for these systems, the possibility of using the waste heat of the diesel locomotive engine is analysed.Materials and methods. The article provides an analysis of the engine waste heat sources, cooling water and exhaust gases. A schematic diagram of exhaust gas heat exchanger for its use in the heating system of passenger cars has been deve loped. As a possible heat-exchange surface of the waste heat exchanger, plate-ribbed, coiled and tube surfaces with longitudinal boundary layer turbulators are proposed. The required area of this surface for the maximum power of the heating system for a passenger train is determined.Results. The article shows the possibility of using engine exhaust heat in the heating system of a 15-car passenger train without involving third-party energy sources.Discussion and conclusion. The obtained results demonstrate a sufficient potential for increasing the efficiency of using the diesel engine fuel energy when utilising its waste heat for the heating system of passenger cars. The selection of a waste heat exchanger is justified based on a performance of 50 % of the peak load on the heating system at the middle position of the controller.

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 main parameter determined in heat engineering tests of heat insulated cars superstructures or the locomotive operator’s cabs is the heat transfer coeffi cient К. The study introduces automated analysis technology for the heat transfer coeffi cient К of enclosure structures of the heat insulated transport means using a remote server. The underlying method provides coeffi cient K of the heat insulated transport means without additional work and time loss for complicated calculations. Personnel of test laboratories involved in heat engineering tests of vehicles possess tools for remotely calculating К, from any point in the world with internet access. To obtain К three controlled parameters measured during the heat engineering tests for 5.5 h including: the difference of the inside and outside temperature of the test object superstructure, total power of the electric heaters and geometric area of the heat transfer surface are sent to the server, after which the user promptly receives the calculated К. The economic effect of introducing the proposed technology for vehicle manufacture is the absence of required tests conducted at the test center; for an operating company — a signifi cant reduction of the idle time of the vehicle at the test center directly affects the loss of profi t. The proposed technology expands the area of operation of the test centers, while calculated К values are offi cially input into the data sheet of the vehicle.

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.