Identification of patterns of non-stationary laminar flow of a viscous fluid at the inlet section of plane-parallel pressure flow

Authors

DOI:

https://doi.org/10.15587/1729-4061.2025.326379

Keywords:

plane-parallel flow, inlet section, unsteady flow, viscous fluid, velocity distribution

Abstract

The inlet region of a plane-parallel pressure flow is the subject of this study. The patterns of variations in the hydrodynamic inlet region under unsteady plane-parallel pressure flow of a viscous fluid are examined in this research. Based on the boundary layer equation and flow characteristics, the boundary conditions of the problem were determined and a boundary value problem was formulated. The problem's boundary conditions were established and a boundary value problem was developed based on the boundary layer equation and flow characteristics. In order to find patterns of velocity change over time and over the length of the inlet region under general boundary conditions, a method for integrating the boundary value conditions was created. Solutions for scenarios with a constant and parabolic velocity distribution in the inlet region were derived from the general solutions. Regularities of pressure and velocity change were found along the entire hydrodynamic inlet region.

Using computer analysis, graphs of velocity changes over time at various points along the entire length of the inlet region are constructed. The patterns of velocity distribution along the entire length of the inlet region depending on time can be seen using graphs. This allows one to estimate the length of the hydrodynamic inlet region and calculate the fluid flow velocity at any point in this region. The findings enable revealing the essence of the processes running in an hydropneumatic automation system's transition sections. Based on the revealed regularities of the hydrodynamic parameters of viscous incompressible liquid during unsteady flows, it is possible to correctly design of the automatic systems' channels of regulating units ensuring their smooth and accurate operation

Author Biographies

Arestak Sarukhanyan, National University of Architecture and Construction of Armenia

Doctor of Sciences, Professor

Department of Water Systems, Hydraulic Engineering and Hydropower

Garnik Vermishyan, National University of Architecture and Construction of Armenia

Candidate of Sciences, Associate Professor

Department of Mathematics

Hovhannes Kelejyan, National University of Architecture and Construction of Armenia

Candidate of Sciences, Associate Professor

Department of Water Systems, Hydraulic Engineering and Hydropower

Pargev Baljyan, National University of Architecture and Construction of Armenia

Doctor of Sciences, Professor

Department of Water Systems, Hydraulic Engineering and Hydropower

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Identification of patterns of non-stationary laminar flow of a viscous fluid at the inlet section of plane-parallel pressure flow

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Published

2025-04-29

How to Cite

Sarukhanyan, A., Vermishyan, G., Kelejyan, H., & Baljyan, P. (2025). Identification of patterns of non-stationary laminar flow of a viscous fluid at the inlet section of plane-parallel pressure flow. Eastern-European Journal of Enterprise Technologies, 2(7 (134), 41–49. https://doi.org/10.15587/1729-4061.2025.326379

Issue

Vol. 2 No. 7 (134) (2025): Applied mechanics

Section

Applied mechanics

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Copyright (c) 2025 Arestak Sarukhanyan, Garnik Vermishyan, Hovhannes Kelejyan, Pargev Baljyan

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