Determination of stress intensity factors for semielliptical surface cracks in the WWER-1000 reactor pressure vessel from the results of solving thermoelasticity boundary value problems based on the mixed mesh-projection scheme of the finite element method

Results of numerical analysis of stress intensity factors K_I for semielliptical surface cracks in the WWER-1000 reactor pressure vessel by emergency cooling simulation with known engineering procedures, the equivalent spatial integration and direct methods are presented. Engineering procedures employ the results of numerical solution of axially symmetric boundary value problems of thermoelasticity based on the mixed mesh-projection scheme of the finite element method implemented in the RELAX software. The three-dimensional K_I computations were performed with the SPACE software. __________ Translated from Problemy Prochnosti, No. 2, pp. 45–51, March–April, 2007.     

Terahertz gyrotrons: State of the art and prospects

The state of the art for terahertz gyrotrons that are needed for various scientific research and practical applications is presented. Powers of 5 kW and 200 kW are obtained at frequencies of 1 and 0.7 THz using pulsed gyrotrons with pulse durations of tens of microseconds. A power of 100 W is demonstrated for cw gyrotrons at frequencies ranging from 0.2 to 0.5 THz.     

Application of the mixed approximation to the solution of two-dimensional problems of the theory of small elastoplastic strains using the finite element method

A triangular finite element that provides the stability and convergence of the mixed approximation is used for the solution of two-dimensional boundary-value problems of the theory of small elastoplastic strains. A system of resolving matrix equations of a mixed type is presented for the solution of which a three-layer iteration algorithm with a preconditioning matrix is used. Numerical results for the solution of model problems obtained by the classical and combined finite element methods are compared. __________ Translated from Problemy Prochnosti, No. 2, pp. 124–136, March–April, 2006.     

The introduction of the software-and-hardware systems developed by ZAO interavtomatika and ZAO MST tornado in power units at thermal power stations

We present the results from introducing the TPTS-51 software-and-hardware system (used by ZAO Interavtomatika) and a software-and-hardware system developed by the firm Tornado at Krasnoyarskenergo power stations.     

Determination of ball bearing contact angle using a scanning acoustic microscope

A technique that allows the direct determination of the position and shape of the region of a ball contact with a ball bearing rim with the use of a scanning acoustic microscope is presented. Based on these data, such important ball bearing parameters as the contact angle and geometrical characteristics of the race of a ball bearing rim can be calculated. The introduction of measuring complexes based on the developed technique will allow a substantial increase in the lifetime, reliability, and competitiveness of manufactured angular-contact ball bearings. The results of the laboratory tests can be used for developing new ball bearings that are characterized by better consumer properties.     

Analysis of the Causes of Failure of a Pipeline Welded Joint

Metal Science and Heat Treatment - An annular welded joint of a pipeline from steel 17G1S with diameter 1020 mm transporting natural gas at a pressure of 5.5 MPa is studied. The residual welding...     

National primary standard for the unit of power of electromagnetic oscillations in waveguides and coaxial lines at frequencies of 0.03–37.5?GHz

The design of a modernized standard for reproduction and transfer of the unit of ultrahigh frequency power in waveguides and coaxial channels and some studies of this system are described.