Tham khảo tài liệu 'tribology - lubricants and lubrication part 9', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 152 Tribology - Lubricants and Lubrication Fig. 13. Longitudinal stresses for problems 25 30 and 33 34 at r1 r r2 Fig. 14. Circumferential stresses for problems 25 30 and 33 34 at r1 r r2 As seen from Figures 15-16 the ơr and ơọ distributions obtained from the analytical calculation practically fully coincide with those obtained from the finite-element calculation which points to a very small error of the latter. 5. Stress-strain state of the three-dimenisonal model of a pipe with corrosion damage under complex loading Consider the problem of determining the stress-strain state of a two-dimenaional model of a pipe in the area of three-dimensional elliptical damage. In calculations we used a model of a pipe with the following geometric characteristics Figure 2 inner without damage and outer radii r1 m and r2 m Three-Dimensional Stress-Strain State of a Pipe with Corrosion Damage Under Complex Loading 153 Fig. 16. the two- 2D 3D . dimensional computer model ơ ị for the three-dimensional computer model aỊ respectively the length of the calculated pipe section L 3 m sizes of elliptical corrosion damage length X width X depth - m X m X m. The pipe mateial had the following characteristics elasticity modulus E1 2-1011 Pa Poisson s coefficient v1 temperature expansion coefficient a 10-5 C-1 thermal conductivity k 43 W m C and the soil parameters were E2 Pa Poisson s coefficient v2 . The coefficient of friction between the pipe and soil was p . The internal pressure in the pipe 1 is ơr r r p 4 MPa. 37
