Thermoelastic stresses in tubes produced from a melt by Stepanov's method

1993 ◽  
Vol 64 (4) ◽  
pp. 379-386
Author(s):  
A. V. Zhdanov ◽  
V. A. Borodin ◽  
L. P. Nikolaeva
Keyword(s):  
Thermoelastic Stresses ◽  
Stepanov’S Method

Maximum temperature drops and thermoelastic stresses in the symmetric heating of prisms and parallelepipeds

1971 ◽  
Vol 3 (12) ◽  
pp. 1405-1406
Author(s):  
N. Yu. Taits ◽  
A. G. Sabel'nikov ◽  
A. N. Minaev ◽  
V. V. Moshura
Keyword(s):  
Maximum Temperature ◽  
Symmetric Heating ◽  
Thermoelastic Stresses

The Effect of Thermoelastic Stresses on Injection Well Fracturing

1985 ◽  
Vol 25 (01) ◽  
pp. 78-88 ◽  
Author(s):  
T.K. Perkins ◽  
J.A. Gonzalez
Keyword(s):  
Hydraulic Fracturing ◽  
Cross Section ◽  
Hydraulic Fracture ◽  
Outer Boundary ◽  
Elliptical Cross Section ◽  
Injection Well ◽  
Plan View ◽  
Elliptical Cross ◽  
Thermoelastic Stresses ◽  
Line Crack

Abstract When a cool fluid such as water is injected into a hot reservoir, a growing region of cooled rock is established around the injection well. The rock matrix within the cooled region contracts, and a thermoelastic stress field is induced around the well. For typical waterflooding of a moderately deep reservoir, horizontal earth stresses may be reduced by several hundred psi. If the injection pressure is too high or if suspended solids in the water plug the formation face at the perforations, the formation will be fractured hydraulically. As the fracture grows, the flow system evolves from an essentially circular geometry in the plan view to one characterized more nearly as elliptical. This paper considers thermoelastic stresses that would result from cooled regions of fixed thickness and of elliptical cross section. The stresses for an infinitely thick reservoir have been deduced from information available in public literature. A numerical method has been developed to calculate thermoelastic stresses induced within elliptically shaped regions of finite thickness. Results of these two approaches were combined, and empirical equations were developed to give an approximate but convenient, explicit method for estimating induced stresses. An example problem is given that shows how this theory can be applied to calculate the fracture lengths, bottomhole pressures (BHP's), and elliptical shapes of the flood front as the injection process progresses. Introduction When fluids are injected into a well, such as during waterflooding or other secondary or tertiary recovery processes, the temperatures of the injected fluids are typically cooler than the in-situ reservoir temperatures. A region of cooled rock forms around each injection well, and this region grows as additional fluid is injected. Formation rock within the cooled region contracts, and this leads to a decrease in horizontal earth stress near the injection well. In Ref. 1, the magnitude of the reduction in horizontal earth stress was given for the case of a radially symmetrical cooled region. Another factor, which may occur simultaneously, is the plugging of formation rock by injected solids. There is extensive literature indicating that waters normally available for injection contain suspended solids. Laboratory tests demonstrate that these waters, when injected into formation rocks, can plug the face of the rock or severely limit injectivity. In field operations, injection often simply continues at a BHP that is high enough to initiate and extend hydraulic fractures." The injected fluid then can leak off readily through the large fracture face area. Because of the lowering of horizontal earth stresses that results from cold fluid injection, hydraulic fracturing pressures can be much lower than would be expected for an ordinary low-leakoff hydraulic fracturing treatment. For this reason, the well operator may not be aware that injected fluid is being distributed through an extensive hydraulic fracture. If injection conditions are such that a hydraulic fracture is created, then the flow system will evolve from an essentially circular geometry in the plan view to one characterized more nearly as elliptical. In this paper, thermoelastic stresses for cooled regions of fixed thickness and of elliptical cross section are determined, and a theory of hydraulic fracturing of injection wells is developed. Conditions under which secondary fractures (perpendicular to the primary, main fracture) will open also are discussed. Finally, an example problem is given to illustrate how this theory can be applied to calculate fracture lengths, BHP'S, and elliptical shapes of the flood front as the injection process progresses. Thermoelastic Stresses in Regions of Elliptical Cross Section If fluid of constant viscosity is injected into a line crack (representing a two-wing, vertical hydraulic fracture), the flood front will progress outward. so its outer boundary at any time can be described approximately as an ellipse that is confocal with the line crack. If the injected fluid is at a temperature different from the formation temperature, a region of changed rock temperature with fairly sharply defined boundaries will progress outward from the injection well but lag behind the flood front. The outer boundary of the region of changed temperature also will be elliptical in its plan view and confocal with the line crack (see Fig. 1). Stresses within the region of altered temperature, as well as stress in the surrounding rock, which remains at its initial temperature, will be changed because of the expansion or contraction of the rock within the region of altered temperature. The thermoelastic stresses within an infinitely tall cylinder of elliptical cross section can be determined from information available in the literature. 10 The interior thermoelastic stresses perpendicular and parallel to the major axes of the ellipse are given by Eqs. 1 and 2, respectively. SPEJ P. 78^

Thermoelastic stresses as a mechanism of electromagnetic-acoustic transformation

1993 ◽  
Vol 36 (10) ◽  
pp. 968-979 ◽  
Author(s):  
A N Vasil'ev ◽  
F M Maallavi ◽  
Moisei I Kaganov
Keyword(s):  
Thermoelastic Stresses

Making Shaped Lithium Niobate and Tantalate Crystals by Stepanov’s Method

1988 ◽  
pp. 223-230
Author(s):  
B. S. Red’kin ◽  
G. A. Satunkin ◽  
V. N. Kurlov ◽  
V. A. Tatarchenko
Keyword(s):  
Lithium Niobate ◽  
Stepanov’S Method

scholarly journals STRESSES IN ANVILS OF VARIOUS CONSTRUCTION OF CONTINUOUS CASTING AND DEFORMATION PLANT AT PRODUCTION OF SHEETS FROM STEEL FOR WELDED PIPES

2019 ◽  
Vol 62 (4) ◽  
pp. 270-275
Author(s):  
O. S. Lekhov ◽  
A. V. Mikhalev ◽  
M. M. Shevelev
Keyword(s):  
Continuous Casting ◽  
Deformation Process ◽  
Comparative Assessment ◽  
Temperature Fields ◽  
Pipe Plant ◽  
Water Cooling ◽  
Advantages And Disadvantages ◽  
Steel Sheets ◽  
Calculation Results ◽  
Thermoelastic Stresses

A comparative assessment of strenuous state of the anvils with and without channels has been carried out for the installation of combined continuous casting and deformation process in the production of steel sheets for welded pipes. The conditions of operation and loading of the anvils of combined continuous casting and deformation process are described. The design of anvil with channels for water cooling and the nature of its loading are given. Using the algorithm for solving problems in the elasticity theory by finite element method, the laws governing the distribution of axial stresses in anvils from the slab reduction force are determined. Effect of the channels for anvils cooling with water on the magnitude and nature of stresses distribution in them from the stress of the slab reduction was estimated. The calculation results of temperature fields and axial and equivalent thermoelastic stresses in anvils with channels are presented for the production process of steel sheets for welded pipes in a combined continuous casting and deformation unit. The article considers regularities of total stresses distribution in anvils with channels. To assess the effect of anvils structure on their stress state, regularities of distribution of thermoelastic and total stresses in strands without channels have been determined. The graph of dependence of thermoelastic stresses in the anvil on temperature of its contact surface is given. Recommendations for choosing the material of the fighters are given. The advantages and disadvantages of the anvils with channels for the unit for combined continuous casting and deformation are described. The parameters of such a pilot installation are presented. The authors also describe the results of an experimental study of the parameters of a combined process at the manufacture installation for continuous casting and deformation of JSC Ural Pipe Plant.

Thermoelastic stresses in HgxCd1−xTe-SiO2-in structures under heat treatments

1992 ◽  
Vol 131 (1) ◽  
pp. K19-K24 ◽  
Author(s):  
L. N. Aleksandrov ◽  
V. Yu. Balandin ◽  
A. V. Dvurechenskii ◽  
O. A. Kulyasova
Keyword(s):  
Heat Treatments ◽  
Thermoelastic Stresses
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