About the authors
First name, Middle name, Last name, Scientific degree, Scientific rank, Current position. Full and brief name of the organization, The organization address. | Davidov A.P. – candidate of technical sciences, associate professor E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it Valiullin M.A. – candidate of technical sciences, associate professor Kazan State University of Architecture and Engineering The organization address: 420043, Russia, Kazan, Zelenaya st., 1 |
Title of the article | The value of the correction factor to the linear momentum at the confluence of two parallel fluid flows in laminar and turbulent modes |
Abstract. | In the calculation of the ventilation elements (tees, air inlets, etc.) it is necessary to estimate the velocity field. To its evaluation the value of the correction factor to the linear momentum в is used, which is the ratio of the local velocity to the mean flow velocity. Until now in the calculation of these devices this factor is accepted equal to one in the turbulent regime and equal to two in the laminar motion. However, experience shows that this is not true. The value of the correction factor for each unit is determined experimentally. This complicates the calculations. In the article the case of a merger of two parallel-moving streams is regarded. The analytical dependences of the correction factor to the linear momentum are obtained both for laminar and turbulent flows. Experimental verification of the obtained relationships conducted on aerodynamic stand for the turbulent regime. The velocity field was received by using the pneumometric tube directly behind the confluence of the streams. Changing of the roughness was performed by gluing a sand with specific size onto the duct wall. By obtained speed values the experimental value of the correction factor to the linear momentum were determined and compared with the analytical dependence. The discrepancy was 2-8 %, which allows the use of the obtained dependences. For laminar mode the experimental studies were conducted using the interferometer. The interferogram shown illustrates the merger of symmetric flows with identical average speeds. |
Keywords. | Ventilation technique, the velocity field, the correction factor, the linear flow momentum, merger flows. |
For citations: | Davidov A.P., Valiullin M.A. The value of the correction factor to the linear momentum at the confluence of two parallel fluid flows in laminar and turbulent modes // Izvestiya KGASU. 2012. №4(22) P.209-214. |