Tham khảo tài liệu 'tribology lubricants and lubrication 2012 part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 142 Tribology - Lubricants and Lubrication With the use of the pipeline fixing type a tests of the pipe dug out of soil in the air are modeled. The stress-strain state of a pipe lying in hard soil without friction in the axial direction is modeled by means of pipe fixing type b while that of a pipe lying in hard soil and rigidly connected with it - by means of pipe fixing type c . Subject to boundary conditions 8 type d a pipe lying in soil having particular mechanical characteristics is modeled. Thus the problem has been stated to make a comparative analysis of the stress-strain states of the pipe with corrosion damage for different combinations of boundary conditions 1 3 6 - 8 d d aT spa s aij sij aij sij aij sij - p T pip .up T p p T .Jp T T r p T T ij sij Uij sij Uij sij 9 where the superscripts p T and T correspond to the stress states caused by internal pressure friction force over the inner surface of the pipe and temperature. In the case of the elastic relationship between stresses and strains the stress states in 9 are connected by the following relations a y T a p aM aij aij aij a T a p -a aij aij aij a. a aT a aij aij aij aij . 10 Further some of the solutions to more than 70 problems of studying the stress-strain state of the pipe cross section in the damage area dot-and-dash line in Figure 1 Kostyuchenko et al. 2007a 2007b Sherbakov et al. 2007b 2008a 2008b Sherbakov 2007b Sosnovskiy et al. 2008 are analyzed. These two-dimensional problems mainly describe the stress-strain states of straight pipes with different-profile damage along the axis. Also with the use of the finite-element method implemented in the software ANSYS the essentially threedimensional stress-strain state of the pipe in the three-dimensional damage area Figure 1 was investigated. 3. Wall friction in the turbulent mineral oil flow in the pipe with corrosion damage Within the framework of the present work hydrodynamic calculation was made of the motion characteristics of a viscous .
