Thermal Stress-strain State Research Articles

Dynamics of thermoelastic half-plane by action of periodic loads and heat flows at its boundary

The problem of the dynamics of a thermoelastic half-space under periodic surface forces and heat flows is solved using the model of coupled thermoelasticity. The Green’s tensor for one boundary value problem is constructed utilizing Fourier transformation. Analytical solutions for arbitrary surface forces and heat flow using the theory of generalized functions are constructed. To solve this boundary value problem, generalized function theory, tensor and differential algebra, the operator method, and integral transformations were used. The solutions obtained make it possible to investigate the thermal stress–strain state of an array with natural and artificial thermal sources and mass power forces acting at its surface.

Algorithm of applying the energy conservation law to study the thermal stress-strain state of a rod of variable cross section with the simultaneous presence of local temperatures, heat exchanges and thermal insulations

The bearing elements of power plants, internal combustion engines of jet engines, nuclear thermal power plants, gas-generating power plants, processing lines, and spacecraft antennas are rods of variable cross-section. They work in a difficult temperature environment. In this paper, we propose an algorithm for applying the fundamental law of energy conservation for a deep study of the resulting thermal-stress-strain state of a rod of limited length and variable cross-section in the simultaneous presence of local temperatures, heat exchange and thermal insulation. At the same time, the obtained solutions in the form of determining the temperature field, displacement, all the components of deformations and stresses, as well as the calculated values of the rod elongation and the resulting axial force are highly accurate at the level of satisfying the energy conservation law.

Calculation of the Thermal Stress-Strain State of Permafrost and Thawing Bases of Buildings in the Presence of Accidental Leaks from Utility Lines

A unified classification of accidental leaks of water from utility lines according to the magnitude of the effect of the permafrost in the base of buildings is developed. The classification is recommended for improving regulatory documents. A procedure is proposed for taking local effects of heat from accidental leaks into account in the calculation of the thermal and thermal stress-strain state of the permafrost in the base of buildings.

Calculation of thermal stress-strain state of soil base under the building on permafrost soil

Article presents problem statement and solution for joint calculation of temperature regime and stress-strain state of permafrost soils under building footing, with consideration of thermal impact from on-surface and buried high-temperature utilities. Based on a series of optimization tasks, a design model for stress-strain state has been developed, solutions of test problems have been obtained and analyzed to determine the degree of influence of temperature stresses and relation of the deformation characteristics of frozen soil in the negative temperature spectrum on the stress distribution and settlement values of frozen soil base under the building.

Simulation of cold rolling of bearing rings taking into account the temperature factor

To ensure the manufacturing accuracy of the bearing rings it is necessary to predict cold rolling process parameters (tool feed rate, forces in the contact area between tool and workpiece, cooling modes, etc.). Therefore, at the process design stage to determine their values, correct mathematical model of the rolling process, which is a related thermoelastoplastic contact problem is needed. The problem of modeling the process of cold rolling of bearing wheels taking into account friction in the contact and influence area of the temperature factor is considered in the paper. Numerical implementation of the 3-dimensional heat conduction problem and the problem of calculating the parameters of thermal stress-strain state of the bearing ring, made of steel SHKH-15 was carried out based on the finite element method using a computer complex DEFORM-3D. Defining relations were set by processing families of deformation diagrams and took into account plastic state of the material in an appropriate range of strain rates and temperatures. Calculations of three-dimensional related contact problem at the two different cooling modes - convective heat transfer with the free air and liquid conducted. The distributions of stress fields, rolling forces and temperature field were obtained. Comparison of the results has shown a significant change in the total force on the tool at different problem statements. Taking into account the temperature factor allows more adequately describe the physical processes in cold rolling of the bearing rings.

Mathematical models of thermal stress-strain state and scale factor error of fiber optic gyro sensors

Mathematical and finite-element models for thermal stress-strain state of the “reel-fiber coil” system precision fiber optic gyro sensor are constructed and studied. An idealized design of the system and the real “reel-fiber coil” are considered. The solution of the thermoelastic contact problems for these systems, qualitative and quantitative evaluations of their mode of deformation, strength, and scale factor errors were obtained. A comparative analysis of systems is carried out and recommendations for improving the accuracy of the sensor are made.

Thermal stress state of a laser-gyroscope housing for use in space

The thermal stress-strain state in the vicinity of the electrical input in an annular laser is simulated during its manufacture and use. Analysis permits the proposal of a new manufacturing technology for the optical contacts and a method of localizing the temperature deformation.

Kinetics of the thermal stress-strain state and strength of the surface layer of material in grinding

Kinetics of the thermal stress-strain state and strength of the surface layer of material in grinding