The mathematical model of conjugate heat exchange is proposed for the turbulent movement of reservoir oil in a vertical well section. The motion of the medium is described using a two-dimensional axisymmetric stationary formulation and boundary layer equations. The movement of the turbulent flow of reservoir oil due to reservoir energy is presented. The liquid medium is a mixture of reservoir oil with dissolved gas and formation water. The results of the numerical modeling are presented in the form of dependences of the changing flow rate, temperature, and mass fraction of paraffin deposits that occur along the full vertical extent of the well. The results obtained describe the thermobaric state of the well under the condition of conjugate heat exchange between the fluid flow and the production pipe.

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The article is devoted to the rational consumption of energy resources when processing of blanks of machine component parts with metal-cutting tools during machine-building production. The scientific and methodological approach to the establishment of energy-efficient processing conditions is proposed, the one is based on the optimization of fabrication procedures according to new energy efficiency criterion. It was given the study of advantages and disadvantages of known methods of fabrication procedures optimization according to the criterion of the lowest specific energy intensity. New integral indicator of energy efficiency of cutting operation is formulated as a ratio of constructional material specific energy intensity to the specific energy consumption in the cutting area. The methods of determining of energy efficiency figure with taking into account the properties of processed material, the behaviors of its deformation and fracture, type of formed chippings and technological purpose of processing are offered. Optimization of machining fabrication procedures with usage of new criterion permits reduction of energy costs in the cutting area by 18-22% in comparison with applicable processing conditions.

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Introduction. The performance of a fire alarm needs to be analyzed to answer the question about its compliance with fire safety requirements. This type of research is frequently performed in the course of a forensic fire investigation. Therefore, it is necessary to identify conditions of fire escalation and safe evacuation of people to assess the fire alarm performance.Purposes and objectives. The purpose of this work is the numerical study of the impact, produced by mathematical models of combustion, characteristics of fire loads and locations of fire beds, on fire alarm performance. Methods. Fire dynamics was field modeled to achieve the goal of this research. The analysis of flame propagation was performed with regard for various fire bed locations to simulate the fire alarm operation.Results and discussion. The fulfillment of safe evacuation conditions for cases of irregular arrangement of smoke detectors was analyzed to develop and test the algorithm for the calculation of the evacuation start time. It is shown that the estimated time of fire detection depends on combustion models employed (their average or complex level), the size of the computational grid, fire load specifications and the location of the fire bed.Conclusions. It is shown that the results of the field modeling of fire propagation and detection time are influenced by combustion models used, fire load specifications and the location of the fire bed in relation to smoke detectors. If the fire alarm fails to perform its functions and, consequently, safe evacuation conditions are not fulfilled, it is necessary either to improve the combustion model or to compare the modeling results obtained for actual and standard smoke detector location patterns.