Assessment of suitability of screen tubes with damages for further use on the basis of mathematical modeling

2019;
: pp. 21-29
https://doi.org/10.23939/mmc2019.01.021
Received: April 23, 2019
Revised: May 29, 2019
Accepted: May 30, 2019
Authors:
1
Pidstryhach Institute for Applied Problems for Mechanics and Mathematics, National Academy of Sciences of Ukraine
2
Pidstryhach Institute for Applied Problems for Mechanics and Mathematics, National Academy of Sciences of Ukraine

Computer simulation of the processes of deformation of screen tubes of boiler units at a thermal power station with wall thinning due to the intense influence of flue gases has been carried out.  The dependences between the maximum stresses in the screen tubes with operational thinnings and the geometrical parameters of the damaged areas of the tubes have been constructed, which allow us to determine the minimum thickness of tubes, for which operating stresses do not exceed a given permissible level. The minimum permissible thickness of the tube in the middle zone of the damaged area has been established. It is shown that the temperature stresses in a pipe under its external heating somewhat compensate for force stresses from the internal pressure.

  1. Mechanics of fracture and strength of materials. Reference book, Vol. 8.  Edit. by V. V. Panasyuk. Kyiv, Publishing House "Academiperiodica'' (2005), (in Ukrainian).
  2. Melekhov R. K., Pokhmursky V. I.  Construction materials of power equipment.  Kyiv, Naukova Dumka (2003), (in Ukrainian).
  3. Demidov S. P.  Theory of elasticity.  Moscow, Vysshaya Shkola (1979), (in Russian).
  4. Kupradze V. D.  Methods of potential in the theory of elasticity.  Moscow, Fizmatgiz (1963), (in Russian).
  5. Mikhlin S. G.  Variational methods in mathematical physics.  Moscow, Nauka (1979), (in Russian).
  6. Nowacki W.  Dynamic Problems of Thermoelasticity.  Springer Netherlands (1975).
  7. Rabotnov Yu. N.  Mechanics of a deformable solid.  Moscow, Nauka (1979), (in Russian).
  8. Properties of steels and alloys used in boiler-turbine construction. Guidelines. (16).  Part One, edit. by L. Ya. Lieberman, M. I. Peysihis.  Leningrad, ONTI CKTI named after I. I. Polzunov (1966), (in Russian).
  9. Sakharov A. S., Altenbach I.  The finite element method in solid mechanics.  Kyiv, Vyscha Shkola (1982), (in Russian).
  10. Zienkiewicz O. C., Taylor R. L.  Finite Element Method, Vol. 1. The Basis.  London, Butterworth Heinemann (2000).
Math. Model. Comput. Vol.6, No.1, pp.21-29 (2019)