Mathematical simulation of thermal condition of a brush contact device in three-dimensional setting
Journal Title: Проблеми машинобудування - Year 2018, Vol 21, Issue 2
Abstract
A detailed review of the existing design of brush contact devices for 200 MW to 600 MW turbo-generators is performed. The peculiarities of brush contact devices working in tandem with turbo-generators of various firms are considered. The main causes of damage are indicated and the ways of development and improvement of the existing design are indicated. An analysis of the methods of calculating heat releases in a brush contact device caused by heat releases of different nature was performed. The most optimal variant of estimation of the influence of a contact spot and quality of brushes on the value of heat releases is specified. The possibility of performing a three-dimensional computation, using the results of the analytical computation together with the CFD method, is shown. For the first time, a computation was performed and an improved method was developed for determining the thermal state of a brush contact device for high and medium-power turbo-generators. It is shown that the temperature values obtained as a result of simulating the thermal state of a brush contact device in the SolidWorks Flow Simulation environment meet the requirements for newly designed electric machines. As criteria for the convergence of the solution, the following values for volume were chosen: minimum, average, and maximum static pressure, average mass flow rate; average heat flux on the indicated surfaces. The calculation was performed until the convergence criterion was reached and at least three purges of the computation area were executed. The calculated error does not exceed the measuring error, which makes it possible to evaluate the operability of a brush contact device at the design stages, and the values obtained do not exceed the maximum permissible temperatures in accordance with the requirements of the normative and technical documentation.
Authors and Affiliations
O. V. Tretiak
Modeling Heat and Mass Exchange Processes in Metal-hydride Installations
Hydrogen as an environmentally friendly energy carrier is increasingly used in various sectors of the economy of industrialized countries, primarily to improve the environmental situation. Regardless of the field of appl...
Chaotic Oscillations of a Kinematically Excited Flat Shell During Geometrically Non-linear Deformation
We study the forced oscillations of a cantilevered flat shell of constant curvature. These movements are excited by a kinematic periodic embedding motion. To describe geometrically non-linear deformation, the non-linear...
Wet Steam Flow Ionization and Prospects to Practically Apply Electrical Discharge Devices in Turbo Installations
This paper considers the experimental studies on steam flow ionization in a supersonic nozzle and possibility of artificial flow ionization influence on unequal-weight processes in the low-pressure cylinder and an increa...
Adaptive piecewise linear approximation of difficult-to-compute functions
The solution of many theoretical and applied problems requires that some functional dependencies be substituted into others, which are more convenient for the implementation of a specific mathematical problem. At the sam...
Numerical analysis of stress-strain state of vertical cylindrical oil tanks with dents
The destruction of vertical cylindrical tanks results in both human and economic losses. Despite constant improvement of the manufacturing technology of cylindrical tanks, a complete analysis of the influence of various...