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The subject of the research is the problem of "hot core" occurrence during intensive cooling of railway rails, which is critically important when preparing rails for fastening in the summer period. The aim of the work is to scientifically substantiate and propose methods for minimizing this phenomenon to ensure a uniform temperature field across the rail section. The research methodology includes an analysis of the influence of the limited thermal conductivity of steel on the formation of a temperature gradient and its negative impact on rail geometry, internal stresses, and fastening accuracy. The work proposes and substantiates methods for reducing the "hot core" effect, including cooling mode management (cascaded and phased intensity reduction), expanding active heat dissipation zones through multi-sided cooling, and applying comprehensive numerical modeling. The research results show that cascaded cooling with pauses effectively redistributes heat from the core to the surface, significantly reducing temperature gradients across the rail section, which is confirmed by numerical simulation results. Phased cooling intensity reduction prevents excessive gradients in later stages. Comprehensive numerical modeling allows not only to predict deformations and stresses but also to visualize optimal temperature fields, optimizing cooling parameters to achieve a uniform fastening temperature. The proposed methods ensure the stability and durability of continuous welded tracks. Effective external heat exchange management is key to solving the "hot core" problem. The implementation of the proposed strategies minimizes temperature gradients, reduces the risk of internal defects, and improves the accuracy of rail fastening, which directly affects their operational strength and safety.

In the article the finite element model of the electrical contact pin wire - collector strip, which takes into account the complex interaction of electric and thermal processes. As the contact wire is selected worn MF-100, the current collection plate - two brands VJZ-metal and graphite. Microgeometry the body surface at the contact point is obtained based on the model of Greenwood - Williamson. It was considered the two extreme cases of possible contact between the contact wire to the plate. The results were analyzed and compared with the known experimental data. Calculated at what proportions contact force and contact current due to burnout occurs spark or arc. Identify ways to improve the model.

The article presents the results of the studied soils on physical and thermophysical characteristics in the territory of the city of Omsk. The lack of such data can lead to erroneous calculations in the design of ground probes using low-potential energy of the earth. A method for determining the minimum distance between wells is proposed, which allows to eliminate soil freezing and increase the efficiency of heat transformers.