Mathematical simulation of thermal condition of a brush contact device in a three-dimensional setting

• Дата: 2018
• Автор: Tretiak, O. V.
• Формат: Стаття
• Мова: English; Russian
• Опубліковано: Journal of Mechanical Engineering 2018
• Теми: brush contact device; thermal state; three-dimensional setting; UDC 621.313.322-82; аппарат щеткодержателей; тепловое состояние; трехмерное моделирование; УДК 621.313.322-82; апарат щіткотримача; тепловий стан; тривимірне моделювання
• Онлайн доступ: https://journals.uran.ua/jme/article/view/135416
• Назва журналу: Journal of Mechanical Engineering

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.