: 48-52
Lviv Polytechnic National University, Department of hydraulics and plumbing
Lviv Polytechnic National University, Department of hydraulics and plumbing
Lviv Polytechnic National University, Department of hydraulics and plumbing

The article deals with mathematical modeling of non-stationary processes non-periodic pressure of the fluid in cylindrical tubes. Based on the Navier-Stokes equations for compressible fluid withdrawn simplified equation for the case of long pipes. It is shown that modeling of single processes, these equations contain only one dimensionless parameter. Identifies conditions which may further simplify these equations to a form that does not contain a dimensionless parameter. Total non-periodic accelerated research process is based on the review model problem for which elected a process in tube for instant pressure changes. Specified the conditions under which you can go to traffic patterns and incompressible fluid movements with high attenuation. The criterion of the transition from laminar to turbulent motion mode that allows you to determine the scope of application of these models movement.To date, no theory calculation since buckling laminar flow regime and transition to a turbulent unsteady flows and therefore no limits applicability of the above models laminar motion, making it necessary to use physical simulation results obtained from experimental data.

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